:root{--bg:#eef1f8;--surface:#fff;--ink:#1b1f3b;--muted:#6b7088;--line:#e2e6f0;--brand:#5350e8;--brand-ink:#3f3cc9;--ok:#14a06b;--ok-soft:#e2f4ec;--bad:#e23d4b;--bad-soft:#fbe6e8;--warn:#f2a33c;--tile:#ffe6a8;--tile-line:#ebcb86;--display:"Space Grotesk", system-ui, -apple-system, Segoe UI, Roboto, sans-serif;--body:system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;--mono:"Space Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;--shadow:0 1px 2px #1b1f3b0f, 0 10px 30px #1b1f3b0f}*{box-sizing:border-box}html,body{margin:0;padding:0}body{background:var(--bg);color:var(--ink);font-family:var(--body);-webkit-font-smoothing:antialiased;touch-action:manipulation;line-height:1.5}.wrap{max-width:980px;margin:0 auto;padding:20px 18px 80px}h1,h2,h3{font-family:var(--display);margin:0;line-height:1.1}button{font-family:inherit}.muted{color:var(--muted)}.topbar{justify-content:space-between;align-items:center;gap:12px;margin-bottom:18px;display:flex}.brand{cursor:pointer;background:0 0;border:0;align-items:center;gap:8px;padding:0;display:flex}.brand .tile{border-radius:7px;width:30px;height:30px;font-size:17px}.brand .name{font-family:var(--display);letter-spacing:-.01em;font-size:20px;font-weight:700}.cfg-chip{color:var(--muted);background:var(--surface);border:1px solid var(--line);white-space:nowrap;border-radius:999px;padding:6px 12px;font-size:13px}.tile{background:var(--tile);color:var(--ink);border:1px solid var(--tile-line);font-family:var(--display);text-transform:uppercase;-webkit-user-select:none;user-select:none;border-radius:10px;justify-content:center;align-items:center;font-weight:700;display:inline-flex;box-shadow:inset 0 -3px #78500024}.wordmark{flex-wrap:wrap;gap:7px;display:flex}.wordmark .tile{width:54px;height:60px;font-size:32px}.hero{margin:6px 0 26px}.hero p{color:var(--muted);max-width:46ch;margin:14px 0 0;font-size:16px}.panel{background:var(--surface);border:1px solid var(--line);box-shadow:var(--shadow);border-radius:18px;margin-bottom:22px;padding:20px}.panel h2{text-transform:uppercase;letter-spacing:.08em;color:var(--muted);font-size:15px;font-weight:700}.panel .eyebrow{align-items:center;gap:8px;margin-bottom:16px;display:flex}.panel .eyebrow .num{font-family:var(--mono);color:var(--brand);font-size:13px;font-weight:700}.eyebrow.collapsible{cursor:pointer;text-align:left;width:100%;font:inherit;background:0 0;border:0;padding:0}.eyebrow.collapsible .chevron{color:var(--muted);margin-left:8px;font-size:14px;transition:transform .2s}.config-summary{font-family:var(--mono);color:var(--muted);text-transform:none;letter-spacing:0;white-space:nowrap;text-overflow:ellipsis;opacity:0;max-width:0;margin-left:auto;font-size:12px;font-weight:400;transition:opacity .2s;overflow:hidden}.panel.is-collapsed .config-summary{opacity:1;max-width:60%}.panel.is-collapsed .eyebrow.collapsible{margin-bottom:0}.panel.is-collapsed .eyebrow.collapsible .chevron{transform:rotate(-90deg)}.collapsible-body{grid-template-rows:1fr;transition:grid-template-rows .25s;display:grid}.collapsible-inner{min-height:0;overflow:hidden}.panel.is-collapsed .collapsible-body{grid-template-rows:0fr}.field{margin-bottom:16px}.field:last-child{margin-bottom:0}label{margin-bottom:7px;font-size:14px;font-weight:600;display:block}textarea,input[type=number]{border:1px solid var(--line);width:100%;font-family:var(--body);color:var(--ink);resize:vertical;background:#fbfcfe;border-radius:12px;padding:11px 13px;font-size:14px}textarea{min-height:96px;font-family:var(--mono);font-size:13px;line-height:1.7}textarea:focus,input:focus{outline:2px solid var(--brand);outline-offset:1px;border-color:#0000}.config-row{grid-template-columns:1fr 1fr;gap:16px;display:grid}.list-preview{border:1px solid var(--line);font-family:var(--mono);color:var(--muted);background:#fbfcfe;border-radius:12px;max-height:72px;margin-top:10px;padding:11px 13px;font-size:12px;line-height:1.7;overflow:auto}.seg{border:1px solid var(--line);background:#f1f3f9;border-radius:12px;gap:4px;padding:4px;display:flex}.seg button{color:var(--muted);cursor:pointer;background:0 0;border:0;border-radius:9px;flex:1;padding:9px 8px;font-size:14px;font-weight:600}.seg button.on{background:var(--surface);color:var(--ink);box-shadow:0 1px 3px #1b1f3b1f}.count-note{color:var(--muted);margin-top:6px;font-size:13px}.config-actions{justify-content:flex-end;margin-top:18px;display:flex}.games,.courses{grid-template-columns:repeat(2,1fr);gap:16px;display:grid}.game-card,.course-card{text-align:left;background:var(--surface);border:1px solid var(--line);cursor:pointer;box-shadow:var(--shadow);border-radius:16px;padding:18px;transition:transform .12s,box-shadow .12s;position:relative}.game-card:hover,.course-card:hover{transform:translateY(-3px);box-shadow:0 10px 26px #1b1f3b1f}.game-card:focus-visible,.course-card:focus-visible{outline:2px solid var(--brand);outline-offset:2px}.game-card .gtile,.course-card .gtile{width:42px;height:46px;margin-bottom:14px;font-size:24px}.game-card h3,.course-card h3{letter-spacing:-.01em;margin-bottom:5px;font-size:18px}.game-card p,.course-card p{color:var(--muted);margin:0;font-size:13px}.game-card .gnum{font-family:var(--mono);color:var(--line);font-size:13px;font-weight:700;position:absolute;top:16px;right:18px}.course-nav{margin-bottom:8px}.vocab-link-wrap{margin:0 0 20px}.vocab-link{color:var(--brand);cursor:pointer;text-underline-offset:3px;background:0 0;border:0;padding:0;font-size:15px;font-weight:600;text-decoration:underline}.vocab-link:hover{color:var(--ink)}#vocabulary-view{display:none}.vocab-toolbar{flex-direction:column;gap:14px;margin-bottom:18px;display:flex}.vocab-mode-field label{color:var(--muted);margin-bottom:6px;font-size:13px;font-weight:600;display:block}.vocab-list-panel{max-height:min(70vh,640px);overflow:auto}.vocab-grid{gap:12px;margin-bottom:24px;display:grid}.vocab-group-header{letter-spacing:.04em;text-transform:uppercase;color:var(--muted);margin:8px 0 12px;font-size:13px;font-weight:700}.vocab-group-header:not(:first-child){margin-top:28px}.vocab-list-panel .vocab-card{text-align:left}.vocab-list-panel .vocab-word{margin-bottom:8px;font-size:18px}.vocab-carousel{flex-direction:column;align-items:center;gap:16px;display:flex}.vocab-counter{color:var(--muted);letter-spacing:.02em;font-size:14px;font-weight:700}.vocab-carousel-viewport{touch-action:pan-y;width:100%;max-width:420px;min-height:180px}.vocab-slide{justify-content:center;align-items:center;min-height:180px;display:flex}.vocab-carousel-nav{gap:16px;display:flex}.vocab-nav-btn{border:1px solid var(--line);background:var(--surface);width:48px;height:48px;color:var(--ink);cursor:pointer;border-radius:12px;font-size:28px;font-weight:600;line-height:1}.vocab-nav-btn:hover{border-color:var(--brand);color:var(--brand)}.vocab-separator{border:2px dashed var(--line);text-align:center;background:#fbfcfe;border-radius:16px;width:100%;padding:32px 20px}.vocab-separator-name{color:var(--ink);font-size:22px;font-weight:700}.vocab-card{border:1px solid var(--line);background:var(--surface);text-align:center;border-radius:12px;width:100%;padding:20px 18px}.vocab-word{color:var(--ink);margin-bottom:12px;font-size:28px;font-weight:700}.vocab-card-head{justify-content:center;align-items:center;gap:10px;display:flex}.vocab-list-panel .vocab-card-head{justify-content:space-between}.vocab-play{border:1px solid var(--line);background:var(--surface);cursor:pointer;border-radius:10px;flex:none;width:38px;height:38px;margin-bottom:12px;font-size:17px;line-height:1}.vocab-play:hover{border-color:var(--brand);background:#f4f4ff}.vocab-play:active{transform:translateY(1px)}.vocab-play.is-playing{border-color:var(--brand);background:#eceaff}.vocab-carousel .vocab-card .sentence{text-align:left;margin:0 auto}.vocab-list-panel .vocab-card .sentence{text-align:left;margin:0}#game-view{display:none}.gv-top{justify-content:space-between;align-items:center;gap:12px;margin-bottom:18px;display:flex}.back{border:1px solid var(--line);background:var(--surface);cursor:pointer;color:var(--ink);border-radius:10px;padding:8px 14px;font-size:14px;font-weight:600}.back:hover{border-color:var(--brand)}.gv-title{align-items:center;gap:10px;display:flex}.gv-title .tile{width:34px;height:38px;font-size:20px}.gv-title h2{font-size:21px}.progress{flex-wrap:wrap;align-items:center;gap:14px;margin-bottom:18px;display:flex}.pbar{background:#e7eaf3;border-radius:999px;flex:1;min-width:140px;height:10px;overflow:hidden}.pbar i{background:var(--brand);width:0;height:100%;transition:width .3s;display:block}.tally{gap:8px;font-size:13px;font-weight:700;display:flex}.tally .g{color:var(--ok)}.tally .r{color:var(--bad)}.stage{background:var(--surface);border:1px solid var(--line);box-shadow:var(--shadow);text-align:center;border-radius:18px;flex-direction:column;justify-content:center;align-items:center;gap:18px;min-height:230px;padding:26px 22px;display:flex}.scramble{flex-wrap:wrap;justify-content:center;gap:8px;display:flex}.scramble .tile{cursor:default;width:46px;height:52px;font-size:26px}.scramble .letter-pick{cursor:pointer;transition:transform 80ms,opacity .15s}.scramble .letter-pick:hover:not(.used){background:#ffd98a;transform:translateY(-2px)}.scramble .letter-pick:active:not(.used){transform:translateY(0)}.scramble .letter-pick.used{opacity:.35;cursor:default;pointer-events:none}.letter-pad{flex-wrap:wrap;justify-content:center;gap:6px;max-width:460px;margin:0 auto;display:flex}.letter-pad .pad-btn{font-family:var(--display);border:1px solid var(--line);background:var(--surface);min-width:36px;height:38px;color:var(--ink);cursor:pointer;border-radius:9px;padding:0 6px;font-size:15px;font-weight:700}.letter-pad .pad-btn:hover{border-color:var(--brand);background:#f4f4ff}.letter-pad .pad-btn:active{transform:translateY(1px)}.letter-pad .pad-back{font-family:var(--mono);font-weight:400}.letter-grid{grid-template-columns:repeat(auto-fit,minmax(58px,1fr));gap:10px;width:100%;max-width:560px;margin:0 auto;display:grid}.letter-grid .letter-key{aspect-ratio:1;cursor:pointer;flex-direction:column;gap:1px;width:100%;padding:0;font-size:24px;transition:transform 80ms,background .15s}.letter-grid .letter-key-ipa{font-family:var(--mono);text-transform:none;color:var(--muted);text-overflow:ellipsis;max-width:100%;padding:0 2px;font-size:10px;font-weight:400;line-height:1;overflow:hidden}.letter-grid .letter-key:hover{background:#ffd98a;transform:translateY(-2px)}.letter-grid .letter-key:active{transform:translateY(0)}.letter-grid .letter-key.is-playing{box-shadow:inset 0 -3px 0 #78500024, 0 0 0 3px var(--brand);background:#ffd98a}#sayIn{text-transform:none;letter-spacing:normal;text-align:left;width:min(420px,86vw);font-family:inherit}.say-ipa{flex-wrap:wrap;justify-content:center;gap:10px 18px;max-width:560px;margin:0 auto;display:flex}.say-ipa-word{flex-direction:column;align-items:center;gap:2px;display:flex}.say-word{font-size:15px;font-weight:600}.say-phonemes{font-family:var(--mono);color:var(--brand);font-size:18px}.say-ipa-note{text-align:center;margin-top:6px;font-size:12px}.say-translation{text-align:center;color:var(--muted);margin-top:10px;font-size:16px;font-style:italic}.say-spinner{vertical-align:-1px;opacity:.7;border:2px solid;border-right-color:#0000;border-radius:50%;width:12px;height:12px;animation:.7s linear infinite say-spin;display:inline-block}@keyframes say-spin{to{transform:rotate(360deg)}}@media (prefers-reduced-motion:reduce){.say-spinner{animation-duration:2.4s}}.answer{flex-wrap:wrap;justify-content:center;align-items:center;gap:10px;display:flex}.answer input{font-family:var(--mono);text-align:center;letter-spacing:.18em;text-transform:uppercase;border:2px solid var(--line);border-radius:12px;width:min(320px,80vw);padding:12px 14px;font-size:20px}.hint{color:var(--muted);font-size:13px}.btn{background:var(--brand);color:#fff;cursor:pointer;border:0;border-radius:12px;padding:12px 22px;font-size:15px;font-weight:700;box-shadow:0 4px 12px #5350e847}.btn:hover{background:var(--brand-ink)}.btn:active{transform:translateY(1px)}.btn.ghost{background:var(--surface);color:var(--ink);border:1px solid var(--line);box-shadow:none}.btn.ok{background:var(--ok);box-shadow:0 4px 12px #14a06b47}.btn.bad{background:var(--bad);box-shadow:0 4px 12px #e23d4b47}.btn-row{flex-wrap:wrap;justify-content:center;gap:12px;display:flex}.big-word{font-family:var(--mono);letter-spacing:.12em;text-transform:uppercase;font-size:34px;font-weight:700}.feedback{min-height:22px;font-size:15px;font-weight:700}.feedback.ok{color:var(--ok)}.feedback.bad{color:var(--bad)}.complete-word{flex-wrap:wrap;justify-content:center;align-items:flex-end;gap:8px;display:flex}.complete-word .fixed{width:42px;height:50px;font-size:24px}.complete-word .slot{text-align:center;text-transform:uppercase;width:42px;height:50px;font-size:24px;font-family:var(--display);border:2px dashed var(--brand);color:var(--ink);background:#f4f4ff;border-radius:10px;font-weight:700}.complete-word .slot:focus{background:#fff;border-style:solid;outline:none}.ws-wrap{flex-wrap:wrap;justify-content:center;align-items:flex-start;gap:22px;width:100%;display:flex}.grid{touch-action:none;-webkit-user-select:none;user-select:none;gap:3px;display:grid}.cell{aspect-ratio:1;min-width:24px;font-family:var(--mono);color:var(--ink);cursor:pointer;background:#f4f6fb;border-radius:6px;justify-content:center;align-items:center;font-size:clamp(11px,2.4vw,16px);font-weight:700;display:flex}.cell.sel{background:var(--warn);color:#fff}.cell.found{background:var(--ok);color:#fff}.ws-words{text-align:left;flex-direction:column;gap:6px;min-width:130px;display:flex}.ws-words .w{font-family:var(--mono);border-radius:6px;padding:3px 4px;font-size:14px}.ws-words .w.done{color:var(--muted);background:var(--ok-soft);text-decoration:line-through}.flash{font-family:var(--mono);letter-spacing:.14em;text-transform:uppercase;font-size:40px;font-weight:700}.countdown{color:var(--muted);font-size:13px}.summary{flex-direction:column;align-items:center;gap:14px;display:flex}.score-ring{font-family:var(--display);font-size:48px;font-weight:700}.summary-score{font-weight:700}.summary-note{font-size:13px}.miss-list{flex-wrap:wrap;justify-content:center;gap:8px;max-width:520px;display:flex}.miss-list .m{font-family:var(--mono);background:var(--bad-soft);color:var(--bad);border-radius:999px;padding:4px 10px;font-size:13px}.rep-grid{grid-template-columns:repeat(2,1fr);gap:16px;display:grid}.rep-card{border:1px solid var(--line);background:#fbfcfe;border-radius:14px;padding:16px}.rep-card h3{margin-bottom:10px;font-size:15px}.rep-stats{gap:18px;margin-bottom:10px;display:flex}.rep-stats div span{font-family:var(--display);font-size:22px;font-weight:700;display:block}.rep-stats div small{color:var(--muted);font-size:12px}.spark{align-items:flex-end;gap:3px;height:38px;margin-top:6px;display:flex}.spark i{background:var(--brand);opacity:.85;border-radius:3px 3px 0 0;flex:1;min-height:3px}.trend{margin-top:8px;font-size:13px;font-weight:700}.trend.up{color:var(--ok)}.trend.down{color:var(--bad)}.trend.flat{color:var(--muted)}.rep-empty{color:var(--muted);font-size:14px}.rep-miss{color:var(--muted);margin-top:8px;font-size:12px}.clear-row{margin-top:16px}.clear-link{color:var(--bad);cursor:pointer;background:0 0;border:0;padding:0;font-size:13px;font-weight:600}.clear-link.armed{text-decoration:underline}.sentence{color:var(--ink);border:1px solid var(--line);background:#f4f6fb;border-radius:12px;max-width:44ch;padding:10px 16px;font-size:15px;line-height:1.7}.sentence .blank{border-bottom:2px solid var(--brand);min-width:62px;font-family:var(--mono);text-transform:uppercase;text-align:center;color:var(--ok);vertical-align:-2px;font-weight:700;line-height:1.2;display:inline-block}.sentence .blank.bad{color:var(--bad);border-bottom-color:var(--bad)}.riddle-loading{justify-content:center;padding:28px 0;display:flex}.riddle-loading svg{width:96px;height:96px}.riddle-loading .rl-track{fill:none;stroke:var(--line);stroke-width:6px}.riddle-loading .rl-arc{fill:none;stroke:var(--brand);stroke-width:6px;stroke-linecap:round;stroke-dasharray:54 160;transform-origin:50%;animation:1.4s linear infinite rl-spin}.riddle-loading .rl-dots circle{fill:var(--brand);opacity:.25;animation:1.4s ease-in-out infinite rl-think}.riddle-loading .rl-dots circle:nth-child(2){animation-delay:.18s}.riddle-loading .rl-dots circle:nth-child(3){animation-delay:.36s}@keyframes rl-spin{to{transform:rotate(360deg)}}@keyframes rl-think{0%,70%,to{opacity:.25;transform:translateY(0)}35%{opacity:1;transform:translateY(-5px)}}@media (prefers-reduced-motion:reduce){.riddle-loading .rl-arc,.riddle-loading .rl-dots circle{animation:none}.riddle-loading .rl-dots circle{opacity:.6}}.riddle-text{color:var(--ink);text-align:center;border:1px solid var(--line);background:#f4f6fb;border-radius:12px;max-width:40ch;padding:14px 18px;font-size:17px;line-height:1.7}.riddle-blanks{flex-wrap:wrap;justify-content:center;gap:6px;display:flex}.riddle-blanks .blank-cell{border-bottom:2px solid var(--brand);width:26px;height:32px;font-family:var(--mono);text-transform:uppercase;text-align:center;color:var(--ok);font-size:20px;font-weight:700}.story-intro,.story-loader,.story-error{flex-direction:column;align-items:center;gap:14px;width:min(620px,100%);display:flex}.story-intro p,.story-loader p,.story-error p{color:var(--muted);margin:0}.story-icon{font-size:48px}.story-loader-book{perspective:260px;width:76px;height:52px;position:relative}.story-loader-book span{border:2px solid var(--brand);background:#eceaff;width:50%;height:100%;position:absolute;top:0}.story-loader-book span:first-child{transform-origin:100%;border-radius:8px 2px 2px 8px;animation:1.4s ease-in-out infinite alternate story-page-left;left:0}.story-loader-book span:last-child{transform-origin:0;border-radius:2px 8px 8px 2px;animation:1.4s ease-in-out infinite alternate story-page-right;right:0}.story-spinner{width:56px;height:56px}.story-spinner-track,.story-spinner-arc{fill:none;stroke-width:4px;stroke-linecap:round}.story-spinner-track{stroke:#eceaff}.story-spinner-arc{stroke:var(--brand);stroke-dasharray:40 86;transform-origin:50%;animation:1.1s linear infinite story-spin}@keyframes story-spin{to{transform:rotate(360deg)}}.story-stage-current{font-weight:700;color:var(--ink)!important}.story-stages{text-align:left;flex-direction:column;gap:8px;width:min(320px,100%);margin:0;padding:0;list-style:none;display:flex}.story-stage{color:var(--muted);align-items:center;gap:10px;font-size:15px;display:flex}.story-stage-mark{border:2px solid #ddd9f5;border-radius:50%;flex:none;place-items:center;width:20px;height:20px;display:grid}.story-stage.is-done{color:var(--ink)}.story-stage.is-done .story-stage-mark{background:var(--brand);border-color:var(--brand)}.story-stage-tick{fill:none;stroke:#fff;stroke-width:2.4px;stroke-linecap:round;stroke-linejoin:round;width:12px;height:12px}.story-stage.is-active{color:var(--ink);font-weight:700}.story-stage.is-active .story-stage-mark{border-color:var(--brand);animation:1.1s ease-in-out infinite story-stage-pulse}@keyframes story-stage-pulse{50%{box-shadow:0 0 0 5px #635bff29}}.story-still-working{font-weight:700;color:var(--ink)!important}@keyframes story-page-left{to{transform:rotateY(18deg)}}@keyframes story-page-right{to{transform:rotateY(-18deg)}}.story-task{text-align:left;flex-direction:column;gap:20px;width:100%;display:flex}.story-task-head{justify-content:space-between;align-items:flex-start;gap:16px;display:flex}.story-kicker{font-family:var(--mono);color:var(--brand);text-transform:uppercase;margin-bottom:5px;font-size:13px;font-weight:700}.story-grammar{max-width:44%;color:var(--muted);text-align:right;font-size:12px}.story-figure{width:min(720px,100%);margin:0 auto}.story-figure img{aspect-ratio:3/2;object-fit:cover;border:1px solid var(--line);background:#f4f6fb;border-radius:16px;width:100%;display:block}.story-figure figcaption{justify-content:flex-end;margin-top:8px;display:flex}.story-report-link{color:var(--muted);cursor:pointer;background:0 0;border:0;padding:2px;font-size:12px;text-decoration:underline}.story-report{border:1px solid var(--line);background:#fbfcfe;border-radius:12px;flex-direction:column;gap:9px;width:min(430px,100%);padding:12px;display:flex}.story-report label{margin:0}.story-report select{border:1px solid var(--line);background:var(--surface);width:100%;color:var(--ink);border-radius:9px;padding:10px}.story-scenes{grid-template-columns:repeat(3,1fr);gap:12px;display:grid}.story-scene{border:1px solid var(--line);background:#fbfcfe;border-radius:14px;padding:14px}.story-scene-head{justify-content:space-between;align-items:center;gap:10px;margin-bottom:7px;display:flex}.story-scene h4{font-family:var(--display);color:var(--brand);margin:0;font-size:14px}.story-scene-play{background:var(--surface);min-height:34px;color:var(--brand);font:700 12px/1 var(--display);cursor:pointer;border:1px solid #5350e84d;border-radius:999px;align-items:center;gap:5px;padding:6px 10px;display:inline-flex}.story-scene-play:hover:not(:disabled){background:#f3f3fe}.story-scene-play:disabled{cursor:wait;opacity:.68}.story-scene p,.story-scene-text{margin:0;font-size:15px;line-height:1.65}.story-word-wrap{display:inline;position:relative}.story-word{color:inherit;font:inherit;line-height:inherit;cursor:pointer;-webkit-text-decoration:underline dotted color-mix(in srgb, var(--accent) 55%, transparent);text-decoration:underline dotted color-mix(in srgb, var(--accent) 55%, transparent);text-underline-offset:.18em;background:0 0;border:0;border-radius:6px;margin:0;padding:.1em .15em;display:inline}.story-word:hover,.story-word.is-selected{background:color-mix(in srgb, var(--accent) 12%, white)}.story-word:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.story-word-help{z-index:2;border:1px solid var(--line);text-align:left;background:#fff;border-radius:12px;min-width:min(240px,72vw);max-width:min(320px,86vw);padding:12px 14px;position:absolute;top:calc(100% + 6px);left:0;box-shadow:0 10px 28px #0f172a1f}.story-word-help-title{color:var(--accent);margin-bottom:6px;font-size:14px;font-weight:700}.story-word-help-form{color:var(--muted);margin:0 0 6px;font-size:12px;line-height:1.4}.story-word-help-definition{margin:0 0 8px;font-size:14px;line-height:1.5}.story-word-help-recap{color:var(--ink);margin:0 0 10px;font-size:13px;line-height:1.45}.story-word-help-recap span{color:var(--muted);font-weight:600}.story-word-help-loading,.story-word-help-error{margin:0 0 8px;font-size:14px;line-height:1.45}.story-word-help-error{color:var(--bad)}.story-word-help-retry,.story-word-help-listen{margin-top:2px}.story-audio-error{color:var(--bad);margin-top:8px;font-size:12px}.story-questions{flex-direction:column;gap:12px;display:flex}.story-question{border:1px solid var(--line);border-radius:14px;padding:16px}.story-question.is-resolved{background:#fbfcfe}.story-question>label{font-size:15px}.story-scaffold{color:var(--brand-ink);flex-wrap:wrap;gap:7px 14px;margin:0 0 10px;font-size:13px;font-weight:600;display:flex}.story-answer-row{align-items:center;gap:10px;display:flex}.story-answer-row input{border:2px solid var(--line);min-width:0;font-family:var(--mono);border-radius:10px;flex:1;padding:11px 12px;font-size:17px}.story-answer-row input:disabled{color:var(--muted);background:#f1f3f9}.story-feedback{min-height:22px;margin-top:8px;font-size:14px;font-weight:700}.story-feedback.ok{color:var(--ok)}.story-feedback.bad{color:var(--bad)}.story-evidence{color:var(--ink);margin-top:7px;font-weight:400;line-height:1.5}.story-task-complete{background:var(--ok-soft);border-radius:12px;flex-wrap:wrap;justify-content:center;align-items:center;gap:14px;padding:14px;display:flex}.summary-tasks,.rep-task-count{font-weight:700}.grammar-passage{flex-direction:column;gap:16px;width:100%;display:flex}.grammar-paragraph{text-align:left;margin:0;font-size:15px;line-height:2.4}.grammar-gap{background:var(--card-2,#f4f4ff);vertical-align:baseline;border-radius:9px;flex-wrap:wrap;align-items:center;gap:5px;margin:0 3px;padding:2px 6px;display:inline-flex}.grammar-gap.is-ok{background:var(--ok-soft)}.grammar-gap.is-bad{background:var(--bad-soft,#ffe9e9)}.grammar-gap-blank{letter-spacing:1px;color:var(--muted);font-weight:700}.grammar-gap-answer{color:var(--ink)}.grammar-gap-options{flex-wrap:wrap;gap:4px;display:inline-flex}.grammar-gap-target{text-transform:uppercase;letter-spacing:.04em;color:var(--muted);align-self:center;font-size:11px}.grammar-option{border:1px solid var(--line,#d9d9e6);background:var(--bg,#fff);font:inherit;cursor:pointer;border-radius:999px;padding:3px 9px;font-size:14px;line-height:1.3}.grammar-option:hover:not(:disabled){border-color:var(--brand)}.grammar-option:disabled{cursor:default;opacity:.45}.grammar-gap.is-ok .grammar-option.is-chosen,.grammar-gap.is-bad .grammar-option.is-chosen{opacity:1;font-weight:700}.grammar-gap.is-bad .grammar-option.is-chosen{color:var(--bad);text-decoration:line-through}.exp-script,.exp-quiz{text-align:left;flex-direction:column;gap:18px;width:100%;display:flex}.exp-head h3{margin:0 0 6px}.exp-section{flex-direction:column;gap:8px;display:flex}.exp-section-title{text-transform:uppercase;letter-spacing:.06em;color:var(--brand);margin:0;font-size:13px}.exp-lines{flex-direction:column;gap:8px;margin:0;padding:0;list-style:none;display:flex}.exp-line{border:1px solid var(--line,#d9d9e6);background:var(--surface,#fff);border-radius:12px;align-items:center;gap:10px;padding:10px 12px;display:flex}.exp-line-text{flex:1;min-width:0}.exp-en{margin:0;font-size:15px;line-height:1.5}.exp-es{color:var(--muted);margin:2px 0 0;font-size:13px;line-height:1.45}.exp-listen{flex:none;min-width:44px;min-height:44px;padding:0 12px}.exp-script-actions{background:var(--bg,#fff);padding:10px 0;position:sticky;bottom:0}.exp-focus{background:var(--card-2,#f4f4ff);text-transform:lowercase;color:var(--brand);white-space:nowrap;border-radius:999px;align-self:flex-start;padding:3px 10px;font-size:12px}.exp-answer-label{color:var(--muted);font-size:13px}.exp-hint{border-left:3px solid var(--brand);background:var(--card-2,#f4f4ff);border-radius:0 12px 12px 0;padding:12px 14px;font-size:15px;line-height:1.5}.exp-answer{border:1px solid var(--line,#d9d9e6);background:var(--surface,#fff);width:100%;color:var(--ink);font:inherit;resize:vertical;border-radius:12px;padding:12px;font-size:16px;line-height:1.5}.exp-answer:focus{border-color:var(--brand);outline:none}.exp-answer:disabled{opacity:.7}.exp-feedback{background:var(--card-2,#f4f4ff);border-radius:12px;flex-direction:column;gap:10px;padding:14px;display:flex}.exp-feedback.is-great,.exp-feedback.is-good{background:var(--ok-soft)}.exp-feedback.is-keep-trying{background:var(--bad-soft,#ffe9e9)}.exp-feedback.is-revealed{background:var(--card-2,#f4f4ff);border-left:3px solid var(--brand)}.exp-explanation{margin:0;font-size:15px;line-height:1.5}.exp-verdict{font-weight:700}.exp-corrected{margin:0;font-size:15px;line-height:1.5}.exp-notes{flex-direction:column;gap:6px;margin:0;padding:0;font-size:14px;line-height:1.5;list-style:none;display:flex}.exp-note-label{text-transform:uppercase;letter-spacing:.05em;color:var(--muted);margin-right:6px;font-size:11px;font-weight:700;display:inline-block}.exp-alternatives ul{margin:6px 0 0;padding-left:20px;font-size:14px;line-height:1.5}.exp-alternatives li+li{margin-top:4px}.exp-encouragement{color:var(--muted);margin:0;font-size:14px}@media (prefers-reduced-motion:reduce){.story-loader-book span,.story-spinner-arc,.story-stage.is-active .story-stage-mark{animation:none}.story-spinner-arc{stroke-dasharray:none;opacity:.55}}.slotrule{border:2px dashed var(--brand);color:var(--brand);background:#f4f4ff}.slotrule.vok{border-style:solid;background:var(--ok)!important;color:#fff!important;border-color:var(--ok)!important}.slotrule.vbad{border-style:solid;background:var(--bad)!important;color:#fff!important;border-color:var(--bad)!important}.rule-opt{min-width:96px}.acc-bar{flex-wrap:wrap;justify-content:center;gap:6px;margin-top:-6px;display:flex}.acc-btn{font-family:var(--mono);border:1px solid var(--line);background:var(--surface);cursor:pointer;min-width:36px;height:36px;color:var(--ink);border-radius:9px;font-size:15px}.acc-btn:hover{border-color:var(--brand);background:#f4f4ff}.acc-btn:active{transform:translateY(1px)}button.tile{cursor:default;font-family:var(--display)}.vsel{cursor:pointer}.vsel.vhi{box-shadow:inset 0 -3px 0 #78500024, 0 0 0 2px var(--brand)}.vsel:hover:not(:disabled){background:#ffd98a}.vsel:disabled{cursor:default}.vok{background:var(--ok)!important;color:#fff!important;border-color:var(--ok)!important}.vbad{background:var(--bad)!important;color:#fff!important;border-color:var(--bad)!important}@media (width<=680px){.config-row,.games,.rep-grid{grid-template-columns:1fr}.wordmark .tile{width:44px;height:50px;font-size:26px}.story-task-head{flex-direction:column}.story-grammar{text-align:left;max-width:none}.story-scenes{grid-template-columns:1fr}.story-answer-row{flex-direction:column;align-items:stretch}.story-answer-row .btn{width:100%}}.toast{background:var(--ink);color:#fff;max-width:min(420px,90vw);font-family:var(--body);text-align:center;opacity:0;pointer-events:none;z-index:1000;border-radius:12px;padding:12px 18px;font-size:14px;font-weight:600;transition:opacity .2s,transform .2s;position:fixed;bottom:24px;left:50%;transform:translate(-50%,16px);box-shadow:0 8px 24px #0000002e}.toast.show{opacity:1;transform:translate(-50%)}.sudoku-grid{margin:12px auto}.sudoku-cell{touch-action:manipulation;border:none;min-width:28px;min-height:28px;padding:0}.sudoku-given{color:var(--ink);cursor:default;background:#e8ecf8}.sudoku-selected{background:var(--warn);color:#fff}.sudoku-given.sudoku-selected{color:var(--ink);background:#d4daf0}.sudoku-border-left{box-shadow:inset 3px 0 #1e233c59}.sudoku-border-top{box-shadow:inset 0 3px #1e233c59}.sudoku-border-left.sudoku-border-top{box-shadow:inset 3px 0 #1e233c59,inset 0 3px #1e233c59}.sudoku-pad{flex-wrap:wrap;justify-content:center;gap:8px;max-width:min(520px,92vw);margin:16px 0 8px;display:flex}.sudoku-pad .math-key{min-width:44px;min-height:44px}.feedback.hint{color:var(--muted)}.math-settings{flex-wrap:wrap;gap:12px 20px;margin:0 0 8px;display:flex}.math-timer{color:var(--muted);flex-wrap:wrap;align-items:center;gap:12px 20px;margin:0 0 10px;font-size:.95rem;display:flex}.math-timer-elapsed{font-family:var(--display);color:var(--ink);font-variant-numeric:tabular-nums}.math-timer-best strong{color:var(--ink);font-family:var(--display);font-variant-numeric:tabular-nums}.math-timer-record{color:var(--accent,#6f6ff0);font-weight:600}.game-1024-hud .math-timer-elapsed,.game-1024-hud .math-timer-best{font-size:inherit}.math-setting{align-items:center;gap:8px;font-size:.95rem;display:flex}.math-setting select{font:inherit;border:1px solid var(--line,#ddd);background:var(--panel,#fff);border-radius:8px;padding:6px 10px}.math-problem{margin:12px 0 16px;font-size:1.15rem;line-height:1.6}.math-problem p{margin:0 0 10px}.md-heading{font-family:var(--display);margin:0 0 8px;font-size:1.05em;font-weight:700}.math-problem p:last-child{margin-bottom:0}.math-problem .katex{font-size:1.05em}.math-loader{flex-direction:column;align-items:center;gap:16px;padding:24px 0;display:flex}.math-spinner{display:block;overflow:visible}.math-spinner .ring-track{fill:none;stroke:var(--line);stroke-width:8px}.math-spinner .ring-arc{fill:none;stroke:url(#mgrad);stroke-width:8px;stroke-linecap:round;stroke-dasharray:70 230;transform-box:view-box;transform-origin:60px 60px;animation:1.1s linear infinite math-spin}.math-spinner .op{font-family:var(--display,sans-serif);fill:var(--brand);text-anchor:middle;opacity:0;transform-box:fill-box;transform-origin:50%;font-size:44px;font-weight:700;animation:3.2s ease-in-out infinite math-op-cycle}.math-spinner .op2{animation-delay:.8s}.math-spinner .op3{animation-delay:1.6s}.math-spinner .op4{animation-delay:2.4s}.math-loader-text{color:var(--muted);font-size:14px;animation:1.4s ease-in-out infinite math-loader-pulse}@keyframes math-spin{to{transform:rotate(360deg)}}@keyframes math-op-cycle{0%{opacity:0;transform:scale(.4)rotate(-25deg)}8%{opacity:1;transform:scale(1.05)rotate(0)}18%{opacity:1;transform:scale(1)rotate(0)}27%{opacity:0;transform:scale(.5)rotate(25deg)}to{opacity:0;transform:scale(.4)rotate(25deg)}}@keyframes math-loader-pulse{0%,to{opacity:.5}50%{opacity:1}}@media (prefers-reduced-motion:reduce){.math-spinner .ring-arc,.math-spinner .op,.math-loader-text{animation:none}.math-spinner .op1{opacity:1}}.math-pad{flex-wrap:wrap;justify-content:center;gap:8px;max-width:360px;margin:4px auto 0;display:flex}.math-key{border:1px solid var(--line);background:var(--surface);min-width:44px;height:44px;font-family:var(--mono,monospace);color:var(--text,#1f2430);cursor:pointer;border-radius:12px;padding:0 12px;font-size:18px;font-weight:700;transition:transform 50ms,background .15s,border-color .15s}.math-key:hover{border-color:var(--brand);background:#f4f4ff}.math-key:active{transform:translateY(1px)}.math-key-back{color:var(--bad,#d33)}.math-card{text-align:left;border-radius:16px;width:min(640px,100%);margin:16px auto 0;padding:0;line-height:1.7;overflow:hidden;box-shadow:0 4px 14px #0000000d}.math-card-head{font-family:var(--display);align-items:center;gap:8px;padding:10px 16px;font-size:15px;font-weight:700;display:flex}.math-card-icon{font-size:18px;line-height:1}.math-card-body{color:var(--text,#1f2430);padding:4px 18px 16px;font-size:15px}.math-card-body p{margin:0 0 10px}.math-card-body p:last-child{margin-bottom:0}.math-card-body ol,.math-card-body ul{margin:6px 0;padding-left:4px;list-style:none}.math-card-body ol>li,.math-card-body ul>li{margin:0;padding:6px 0 6px 40px;position:relative}.math-card-body .math-code{font-family:var(--mono,monospace);white-space:pre;background:#0000000d;border:1px solid #00000014;border-radius:10px;margin:8px 0;padding:10px 14px;font-size:15px;line-height:1.5;overflow-x:auto}.math-card-body ol>li:before{content:attr(data-n);width:26px;height:26px;font-family:var(--display);color:#fff;border-radius:50%;place-items:center;font-size:13px;font-weight:700;display:grid;position:absolute;top:6px;left:0}.math-card-body ul>li:before{content:"✏️";font-size:15px;position:absolute;top:6px;left:6px}.math-method+.math-method{border-top:2px dashed #50a0ff59;margin-top:14px;padding-top:14px}.math-method-title{font-family:var(--display);color:#24557a;flex-wrap:wrap;align-items:center;gap:8px;margin-bottom:4px;font-size:15px;font-weight:700;display:flex}.math-method-num{color:#fff;background:linear-gradient(135deg,#5aa0ff,#6f6ff0);border-radius:999px;padding:2px 10px;font-size:12px;display:inline-block}.math-hint{background:#fffaf0;border:1px solid #ffc40066}.math-hint .math-card-head{color:#8a6100;background:#ffc4002e}.math-solution{background:#f5f9ff;border:1px solid #50a0ff59}.math-solution .math-card-head{color:#24557a;background:#50a0ff29}.math-solution .math-card-body ol>li:before{background:linear-gradient(135deg,#5aa0ff,#6f6ff0)}lexia-scratch-pad.scratch-pad{text-align:left;align-self:stretch;width:100%;margin-top:8px;display:block}.scratch-pad.panel{border:1px solid var(--line);background:var(--surface);border-radius:16px;padding:12px 14px;box-shadow:0 2px 8px #0000000a}.scratch-pad-toggle{-webkit-user-select:none;user-select:none;align-items:center;gap:8px;width:100%;margin-bottom:0;display:flex}.scratch-pad-toggle .scratch-pad-title{font-family:var(--display);flex:none;margin:0;font-size:15px;font-weight:700}.scratch-pad-icon{font-size:18px;line-height:1}.scratch-pad-heights{gap:4px;margin-left:auto;margin-right:4px;display:flex}.scratch-height-btn{border:1px solid var(--line);background:var(--surface);min-width:32px;height:32px;font-family:var(--mono);cursor:pointer;color:var(--muted);border-radius:8px;padding:0 8px;font-size:11px;font-weight:700}.scratch-height-btn.on{border-color:var(--brand);color:var(--brand);background:#f4f4ff}.scratch-height-btn:disabled{opacity:.45;cursor:default}.scratch-pad.is-collapsed .scratch-pad-heights{opacity:.55}.scratch-pad:not(.is-collapsed){touch-action:none;overscroll-behavior:contain}.scratch-pad-body{touch-action:none}.scratch-toolbar{-webkit-user-select:none;user-select:none;flex-wrap:wrap;align-items:center;gap:10px;margin-bottom:10px;display:flex}.scratch-toolbar.is-drawing{pointer-events:none}.scratch-tools,.scratch-colors,.scratch-sizes{flex-wrap:wrap;align-items:center;gap:6px;display:flex}.scratch-tool{border:1px solid var(--line);background:var(--surface);cursor:pointer;min-height:44px;color:var(--ink);-webkit-user-select:none;user-select:none;border-radius:10px;padding:8px 12px;font-size:13px;font-weight:600}.scratch-tool.on{border-color:var(--brand);color:var(--brand-ink);background:#f4f4ff}.scratch-tool:disabled{opacity:.45;cursor:default}.scratch-tool-clear{color:var(--bad)}.scratch-color{border:2px solid var(--line);background:var(--swatch);cursor:pointer;-webkit-user-select:none;user-select:none;border-radius:999px;width:44px;height:44px;padding:0}.scratch-color.on{border-color:var(--ink);box-shadow:0 0 0 2px var(--surface), 0 0 0 4px var(--brand)}.scratch-size{border:1px solid var(--line);background:var(--surface);cursor:pointer;-webkit-user-select:none;user-select:none;border-radius:10px;min-width:44px;min-height:44px;padding:8px 10px;font-size:12px;font-weight:600}.scratch-size.on{border-color:var(--brand);background:#f4f4ff}.scratch-canvas-wrap{border:1px solid var(--line);touch-action:none;background:#fff;border-bottom:none;border-radius:12px 12px 0 0;width:100%;position:relative;overflow:hidden}.scratch-canvas{touch-action:none;-webkit-user-select:none;user-select:none;cursor:crosshair;width:100%;height:100%;display:block}.scratch-canvas.is-erase{cursor:none}.scratch-eraser-cursor{width:var(--eraser-size,24px);height:var(--eraser-size,24px);margin-left:calc(var(--eraser-size,24px) / -2);margin-top:calc(var(--eraser-size,24px) / -2);pointer-events:none;z-index:2;background:#5350e81a;border:2px solid #5350e88c;border-radius:999px;display:none;position:absolute;top:0;left:0;box-shadow:0 0 0 1px #ffffffd9}.scratch-resize-handle{cursor:ns-resize;touch-action:none;border:1px solid var(--line);background:linear-gradient(#5350e814,#5350e81f);border-radius:0 0 12px 12px;width:100%;height:14px;position:relative}.scratch-resize-handle:after{content:"";background:var(--line);border-radius:999px;width:36px;height:4px;position:absolute;top:50%;left:50%;transform:translate(-50%,-50%)}#game-view.scratch-drawing-active{touch-action:none}#stage.scratch-drawing-active .math-pad,#stage.scratch-drawing-active .answer,#stage.scratch-drawing-active .btn-row,#stage.scratch-drawing-active .scratch-toolbar,#stage.scratch-drawing-active .scratch-pad-toggle,#stage.scratch-drawing-active .scratch-height-btn,#stage.scratch-drawing-active .math-problem,#stage.scratch-drawing-active .hint,#stage.scratch-click-guard .math-pad,#stage.scratch-click-guard .answer,#stage.scratch-click-guard .btn-row,#stage.scratch-click-guard .scratch-toolbar,#stage.scratch-click-guard .scratch-pad-toggle,#stage.scratch-click-guard .scratch-height-btn{pointer-events:none}#stage.scratch-drawing-active .math-problem,#stage.scratch-drawing-active .hint{-webkit-user-select:none;user-select:none}.game-1024{flex-direction:column;gap:12px;display:flex}.game-1024-hint{line-height:1.45}.game-1024-hint>div+div{margin-top:4px}.game-1024-hud{color:var(--muted);flex-wrap:wrap;gap:16px 24px;font-size:.95rem;display:flex}.game-1024-hud strong{color:var(--ink);font-family:var(--display)}.game-1024-board{--grid-size:4;--tile-gap:8px;--tile-size:min(72px, calc((100vw - 72px) / var(--grid-size)));width:calc(var(--grid-size) * var(--tile-size) + (var(--grid-size) - 1) * var(--tile-gap) + 20px);touch-action:none;-webkit-user-select:none;user-select:none;background:#c9c5e8;border-radius:12px;max-width:100%;margin:0 auto;padding:10px;position:relative}.game-1024-grid{grid-template-columns:repeat(var(--grid-size), var(--tile-size));grid-template-rows:repeat(var(--grid-size), var(--tile-size));gap:var(--tile-gap);display:grid}.game-1024 .tile-cell{background:#ffffff73;border-radius:8px;min-height:0}.game-1024-tiles{pointer-events:none;position:absolute;inset:10px}.game-1024 .tile-piece{width:var(--tile-size);height:var(--tile-size);font-family:var(--display);color:var(--ink);will-change:left, top, transform;z-index:1;border-radius:8px;justify-content:center;align-items:center;font-size:clamp(.85rem,4vw,1.35rem);font-weight:700;transition:left .14s ease-in-out,top .14s ease-in-out;display:flex;position:absolute;top:0;left:0}.game-1024 .tile-piece.tile-spawn{animation:.16s ease-out tile-spawn}.game-1024 .tile-piece.tile-merge{z-index:2;animation:.16s ease-out tile-merge}@keyframes tile-spawn{0%{opacity:.4;transform:scale(.35)}to{opacity:1;transform:scale(1)}}@keyframes tile-merge{0%{transform:scale(1)}45%{transform:scale(1.14)}to{transform:scale(1)}}.game-1024 .tile-1{background:#eee4ff}.game-1024 .tile-2{background:#ddd0ff}.game-1024 .tile-3{background:#c9b8ff}.game-1024 .tile-4{color:#fff;background:#b5a0ff}.game-1024 .tile-5{color:#fff;background:#9a82f5}.game-1024 .tile-6{color:#fff;background:#7f66e8}.game-1024 .tile-7{color:#fff;background:#6550d4}.game-1024 .tile-8,.game-1024 .tile-9,.game-1024 .tile-10,.game-1024 .tile-11,.game-1024 .tile-12{background:var(--brand);color:#fff;font-size:clamp(.7rem,3.2vw,1.1rem)}.game-1024-arrows{flex-direction:column;align-items:center;gap:6px;margin:4px auto 0;display:flex}.game-1024-arrows-mid{gap:48px;display:flex}.game-1024-arrow{border:1px solid var(--line);background:var(--surface);cursor:pointer;width:52px;height:52px;box-shadow:var(--shadow);color:var(--ink);border-radius:12px;font-size:1.4rem}.game-1024-arrow:disabled{opacity:.45;cursor:not-allowed}.game-1024-overlay{z-index:2;background:#1b1f3b8c;border-radius:12px;justify-content:center;align-items:center;padding:12px;display:flex;position:absolute;inset:0}.game-1024-overlay-card{background:var(--surface);text-align:center;max-width:100%;box-shadow:var(--shadow);border-radius:12px;padding:16px 18px}.game-1024-overlay-title{font-family:var(--display);margin-bottom:6px;font-size:1.1rem;font-weight:700}.game-1024-overlay-sub{color:var(--muted);margin-bottom:10px;font-size:.92rem}.game-1024-overlay-best{margin-bottom:10px}.game-1024-chain{text-align:left;color:var(--muted);border-top:1px solid var(--line);padding-top:10px;font-size:.88rem}.game-1024-chain-values{font-family:var(--mono);color:var(--ink);word-break:break-word;margin:6px 0;font-size:.82rem}.game-1024-chain-hint{font-size:.85rem}.teacher-prompt{text-align:left;flex-direction:column;align-self:stretch;gap:12px;width:100%;padding:4px 0 8px;display:flex}.teacher-intro{text-align:center;flex-direction:column;align-items:center;gap:4px;display:flex}.teacher-intro__icon{font-size:42px}.teacher-intro h3{margin:0}.teacher-intro p{color:var(--muted);margin:0}.teacher-prompt__label{font-weight:600}.teacher-prompt__field{border:1px solid var(--line);width:100%;min-height:96px;font-family:var(--body);background:var(--surface);color:var(--ink);resize:vertical;border-radius:10px;padding:10px 12px;font-size:1rem}.teacher-prompt__field:focus-visible{outline:2px solid var(--brand);outline-offset:2px}.teacher-prompt__row{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:10px;display:flex}.teacher-prompt__hint{color:var(--muted)}.teacher-suggestions{flex-wrap:wrap;gap:8px;display:flex}.chip{border:1px solid var(--line);background:var(--surface);color:var(--ink);font:inherit;cursor:pointer;border-radius:999px;padding:6px 12px}.chip:hover{background:var(--bg)}.chip:focus-visible{outline:2px solid var(--brand);outline-offset:2px}.teacher-history{border:1px solid var(--line);background:var(--surface);border-radius:10px;padding:8px 12px}.teacher-history__list{flex-direction:column;gap:6px;margin:8px 0 0;padding:0;list-style:none;display:flex}.teacher-history__item{justify-content:space-between;align-items:center;gap:8px;display:flex}.teacher-history__open{text-align:left;cursor:pointer;color:var(--ink);background:0 0;border:0;flex-direction:column;flex:1;padding:6px 4px;display:flex}.teacher-history__open small{color:var(--muted)}.teacher-history__remove{color:var(--muted);cursor:pointer;background:0 0;border:0;font-size:.85rem;text-decoration:underline}.teacher-loading{text-align:center;flex-direction:column;align-items:center;gap:14px;padding:24px 8px;display:flex}.teacher-loading__spinner{font-size:36px;animation:2s linear infinite teacher-spin}@keyframes teacher-spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.teacher-loading__stages{flex-direction:column;gap:6px;margin:0;padding:0;list-style:none;display:flex}.teacher-loading__stage{color:var(--muted)}.teacher-loading__stage.is-active{color:var(--brand-ink);font-weight:600}.teacher-loading__stage.is-done{color:var(--ok)}.teacher-loading__hint{color:var(--muted)}.teacher-error{background:var(--bad-soft);color:var(--ink);border-radius:10px;flex-direction:column;gap:8px;padding:12px;display:flex}.teacher-error__actions{gap:8px;display:flex}.teacher-lesson{text-align:left;flex-direction:column;align-self:stretch;gap:12px;width:100%;display:flex}.teacher-lesson__actions{flex-wrap:wrap;justify-content:flex-start;gap:8px;display:flex}.teacher-lesson__body{background:var(--surface);border:1px solid var(--line);color:var(--ink);overflow-wrap:break-word;text-align:left;border-radius:12px;padding:20px 24px;font-size:.95rem;line-height:1.6}.teacher-lesson__body>:first-child{margin-top:0}.teacher-lesson__body>:last-child{margin-bottom:0}.teacher-lesson__body h1{border-bottom:1px solid var(--line);margin:0 0 12px;padding-bottom:8px;font-size:1.45rem;line-height:1.25}.teacher-lesson__body h2{color:var(--brand-ink);margin:22px 0 8px;font-size:1.1rem;line-height:1.3}.teacher-lesson__body h3{margin:16px 0 6px;font-size:1rem}.teacher-lesson__body p{margin:0 0 10px}.teacher-lesson__body ul,.teacher-lesson__body ol{margin:0 0 12px;padding-left:22px}.teacher-lesson__body li{margin:2px 0}.teacher-lesson__body li>p{margin:0 0 4px}.teacher-lesson__body strong{color:var(--brand-ink)}.teacher-lesson__body code{background:var(--bg);font-family:var(--mono);border-radius:4px;padding:1px 6px;font-size:.85em}.teacher-lesson__body pre{background:var(--bg);border:1px solid var(--line);border-radius:8px;margin:8px 0 14px;padding:10px 14px;overflow-x:auto}.teacher-lesson__body pre code{background:0 0;padding:0;font-size:.85em;line-height:1.5}.teacher-lesson__body table{border-collapse:collapse;width:100%;margin:10px 0 16px;font-size:.9rem}.teacher-lesson__body th,.teacher-lesson__body td{border:1px solid var(--line);text-align:left;vertical-align:top;padding:6px 10px}.teacher-lesson__body th{background:var(--bg);font-weight:600}.teacher-lesson__body blockquote{border-left:3px solid var(--brand);color:var(--muted);background:var(--bg);border-radius:0 8px 8px 0;margin:10px 0;padding:4px 12px}.teacher-callout{--callout-tint:var(--brand);--callout-bg:var(--bg);--callout-label:"INFO";background:var(--callout-bg);border-left:4px solid var(--callout-tint);border-radius:8px;margin:12px 0;padding:10px 14px 10px 42px;font-size:.9rem;line-height:1.5;position:relative}.teacher-callout:before{content:"ℹ";background:var(--callout-tint);color:#fff;border-radius:999px;justify-content:center;align-items:center;width:20px;height:20px;font-size:12px;font-weight:700;display:flex;position:absolute;top:9px;left:12px}.teacher-callout--tip{--callout-tint:var(--ok);--callout-bg:var(--ok-soft)}.teacher-callout--tip:before{content:"✓"}.teacher-callout--beyond-a1{--callout-tint:var(--warn);--callout-bg:#fff4dd}.teacher-callout--beyond-a1:before{content:"★"}.teacher-callout--warning{--callout-tint:var(--bad);--callout-bg:var(--bad-soft)}.teacher-callout--warning:before{content:"!"}.teacher-callout p{margin:0}.teacher-callout p+p{margin-top:6px}.teacher-example-audio-btn{border:1px solid var(--line);background:var(--surface);cursor:pointer;vertical-align:-3px;border-radius:999px;justify-content:center;align-items:center;width:24px;height:24px;margin-left:4px;padding:0;font-size:11px;line-height:1;display:inline-flex}.teacher-example-audio-btn:hover{background:var(--bg);border-color:var(--brand)}.teacher-example-audio-btn.is-playing{border-color:var(--brand);color:var(--brand-ink);background:var(--ok-soft)}.teacher-example-audio-btn.is-unavailable{opacity:.4;cursor:not-allowed}.teacher-example-audio-btn.is-error{border-color:var(--bad);color:var(--bad)}@media (prefers-reduced-motion:reduce){*{transition:none!important}}@font-face{font-display:block;font-family:KaTeX_AMS;font-style:normal;font-weight:400;src:url(/assets/KaTeX_AMS-Regular-BQhdFMY1.woff2)format("woff2"),url(/assets/KaTeX_AMS-Regular-DMm9YOAa.woff)format("woff"),url(/assets/KaTeX_AMS-Regular-DRggAlZN.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Caligraphic;font-style:normal;font-weight:700;src:url(/assets/KaTeX_Caligraphic-Bold-Dq_IR9rO.woff2)format("woff2"),url(/assets/KaTeX_Caligraphic-Bold-BEiXGLvX.woff)format("woff"),url(/assets/KaTeX_Caligraphic-Bold-ATXxdsX0.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Caligraphic;font-style:normal;font-weight:400;src:url(/assets/KaTeX_Caligraphic-Regular-Di6jR-x-.woff2)format("woff2"),url(/assets/KaTeX_Caligraphic-Regular-CTRA-rTL.woff)format("woff"),url(/assets/KaTeX_Caligraphic-Regular-wX97UBjC.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Fraktur;font-style:normal;font-weight:700;src:url(/assets/KaTeX_Fraktur-Bold-CL6g_b3V.woff2)format("woff2"),url(/assets/KaTeX_Fraktur-Bold-BsDP51OF.woff)format("woff"),url(/assets/KaTeX_Fraktur-Bold-BdnERNNW.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Fraktur;font-style:normal;font-weight:400;src:url(/assets/KaTeX_Fraktur-Regular-CTYiF6lA.woff2)format("woff2"),url(/assets/KaTeX_Fraktur-Regular-Dxdc4cR9.woff)format("woff"),url(/assets/KaTeX_Fraktur-Regular-CB_wures.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:normal;font-weight:700;src:url(/assets/KaTeX_Main-Bold-Cx986IdX.woff2)format("woff2"),url(/assets/KaTeX_Main-Bold-Jm3AIy58.woff)format("woff"),url(/assets/KaTeX_Main-Bold-waoOVXN0.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:italic;font-weight:700;src:url(/assets/KaTeX_Main-BoldItalic-DxDJ3AOS.woff2)format("woff2"),url(/assets/KaTeX_Main-BoldItalic-SpSLRI95.woff)format("woff"),url(/assets/KaTeX_Main-BoldItalic-DzxPMmG6.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:italic;font-weight:400;src:url(/assets/KaTeX_Main-Italic-NWA7e6Wa.woff2)format("woff2"),url(/assets/KaTeX_Main-Italic-BMLOBm91.woff)format("woff"),url(/assets/KaTeX_Main-Italic-3WenGoN9.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Main;font-style:normal;font-weight:400;src:url(/assets/KaTeX_Main-Regular-B22Nviop.woff2)format("woff2"),url(/assets/KaTeX_Main-Regular-Dr94JaBh.woff)format("woff"),url(/assets/KaTeX_Main-Regular-ypZvNtVU.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Math;font-style:italic;font-weight:700;src:url(/assets/KaTeX_Math-BoldItalic-CZnvNsCZ.woff2)format("woff2"),url(/assets/KaTeX_Math-BoldItalic-iY-2wyZ7.woff)format("woff"),url(/assets/KaTeX_Math-BoldItalic-B3XSjfu4.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Math;font-style:italic;font-weight:400;src:url(/assets/KaTeX_Math-Italic-t53AETM-.woff2)format("woff2"),url(/assets/KaTeX_Math-Italic-DA0__PXp.woff)format("woff"),url(/assets/KaTeX_Math-Italic-flOr_0UB.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_SansSerif;font-style:normal;font-weight:700;src:url(/assets/KaTeX_SansSerif-Bold-D1sUS0GD.woff2)format("woff2"),url(/assets/KaTeX_SansSerif-Bold-DbIhKOiC.woff)format("woff"),url(/assets/KaTeX_SansSerif-Bold-CFMepnvq.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_SansSerif;font-style:italic;font-weight:400;src:url(/assets/KaTeX_SansSerif-Italic-C3H0VqGB.woff2)format("woff2"),url(/assets/KaTeX_SansSerif-Italic-DN2j7dab.woff)format("woff"),url(/assets/KaTeX_SansSerif-Italic-YYjJ1zSn.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_SansSerif;font-style:normal;font-weight:400;src:url(/assets/KaTeX_SansSerif-Regular-DDBCnlJ7.woff2)format("woff2"),url(/assets/KaTeX_SansSerif-Regular-CS6fqUqJ.woff)format("woff"),url(/assets/KaTeX_SansSerif-Regular-BNo7hRIc.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Script;font-style:normal;font-weight:400;src:url(/assets/KaTeX_Script-Regular-D3wIWfF6.woff2)format("woff2"),url(/assets/KaTeX_Script-Regular-D5yQViql.woff)format("woff"),url(/assets/KaTeX_Script-Regular-C5JkGWo-.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size1;font-style:normal;font-weight:400;src:url(/assets/KaTeX_Size1-Regular-mCD8mA8B.woff2)format("woff2"),url(/assets/KaTeX_Size1-Regular-C195tn64.woff)format("woff"),url(/assets/KaTeX_Size1-Regular-Dbsnue_I.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size2;font-style:normal;font-weight:400;src:url(/assets/KaTeX_Size2-Regular-Dy4dx90m.woff2)format("woff2"),url(/assets/KaTeX_Size2-Regular-oD1tc_U0.woff)format("woff"),url(/assets/KaTeX_Size2-Regular-B7gKUWhC.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size3;font-style:normal;font-weight:400;src:url(data:font/woff2;base64,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)format("woff2"),url(/assets/KaTeX_Size3-Regular-CTq5MqoE.woff)format("woff"),url(/assets/KaTeX_Size3-Regular-DgpXs0kz.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Size4;font-style:normal;font-weight:400;src:url(/assets/KaTeX_Size4-Regular-Dl5lxZxV.woff2)format("woff2"),url(/assets/KaTeX_Size4-Regular-BF-4gkZK.woff)format("woff"),url(/assets/KaTeX_Size4-Regular-DWFBv043.ttf)format("truetype")}@font-face{font-display:block;font-family:KaTeX_Typewriter;font-style:normal;font-weight:400;src:url(/assets/KaTeX_Typewriter-Regular-CO6r4hn1.woff2)format("woff2"),url(/assets/KaTeX_Typewriter-Regular-C0xS9mPB.woff)format("woff"),url(/assets/KaTeX_Typewriter-Regular-D3Ib7_Hf.ttf)format("truetype")}.katex{text-indent:0;text-rendering:auto;font:1.21em/1.2 KaTeX_Main,Times New Roman,serif;position:relative}.katex *{border-color:currentColor;-ms-high-contrast-adjust:none!important}.katex .katex-version:after{content:"0.17.0"}.katex .katex-mathml{clip-path:inset(50%);border:0;width:1px;height:1px;padding:0;position:absolute;overflow:hidden}.katex .katex-html>.newline{display:block}.katex .base{white-space:nowrap;width:min-content;position:relative}.katex .base,.katex .strut{display:inline-block}.katex .textbf{font-weight:700}.katex .textit{font-style:italic}.katex .textrm{font-family:KaTeX_Main}.katex .textsf{font-family:KaTeX_SansSerif}.katex .texttt{font-family:KaTeX_Typewriter}.katex .mathnormal{font-family:KaTeX_Math;font-style:italic}.katex .mathit{font-family:KaTeX_Main;font-style:italic}.katex .mathrm{font-style:normal}.katex .mathbf{font-family:KaTeX_Main;font-weight:700}.katex .boldsymbol{font-family:KaTeX_Math;font-style:italic;font-weight:700}.katex .amsrm,.katex .mathbb,.katex .textbb{font-family:KaTeX_AMS}.katex .mathcal{font-family:KaTeX_Caligraphic}.katex .mathfrak,.katex .textfrak{font-family:KaTeX_Fraktur}.katex .mathboldfrak,.katex .textboldfrak{font-family:KaTeX_Fraktur;font-weight:700}.katex .mathtt{font-family:KaTeX_Typewriter}.katex .mathscr,.katex .textscr{font-family:KaTeX_Script}.katex .mathsf,.katex .textsf{font-family:KaTeX_SansSerif}.katex .mathboldsf,.katex .textboldsf{font-family:KaTeX_SansSerif;font-weight:700}.katex .mathitsf,.katex .mathsfit,.katex .textitsf{font-family:KaTeX_SansSerif;font-style:italic}.katex .mainrm{font-family:KaTeX_Main;font-style:normal}.katex .vlist-t{border-collapse:collapse;table-layout:fixed;display:inline-table}.katex .vlist-r{display:table-row}.katex .vlist{vertical-align:bottom;display:table-cell;position:relative}.katex .vlist>span{height:0;display:block;position:relative}.katex .vlist>span>span{display:inline-block}.katex .vlist>span>.pstrut{width:0;overflow:hidden}.katex .vlist-t2{margin-right:-2px}.katex .vlist-s{vertical-align:bottom;width:2px;min-width:2px;font-size:1px;display:table-cell}.katex .vbox{flex-direction:column;align-items:baseline;display:inline-flex}.katex .hbox{width:100%}.katex .hbox,.katex .thinbox{flex-direction:row;display:inline-flex}.katex .thinbox{width:0;max-width:0}.katex .msupsub{text-align:left}.katex .mfrac>span>span{text-align:center}.katex .mfrac .frac-line{border-bottom-style:solid;width:100%;display:inline-block}.katex .hdashline,.katex .hline,.katex .mfrac .frac-line,.katex .overline .overline-line,.katex .rule,.katex .underline .underline-line{min-height:1px}.katex .mspace{display:inline-block}.katex .smash{line-height:0;display:inline}.katex .clap,.katex .llap,.katex .rlap{width:0;position:relative}.katex .clap>.inner,.katex .llap>.inner,.katex .rlap>.inner{position:absolute}.katex .clap>.fix,.katex .llap>.fix,.katex .rlap>.fix{display:inline-block}.katex .llap>.inner{right:0}.katex .clap>.inner,.katex .rlap>.inner{left:0}.katex .clap>.inner>span{margin-left:-50%;margin-right:50%}.katex .rule{border:0 solid;display:inline-block;position:relative}.katex .hline,.katex .overline .overline-line,.katex .underline .underline-line{border-bottom-style:solid;width:100%;display:inline-block}.katex .hdashline{border-bottom-style:dashed;width:100%;display:inline-block}.katex .sqrt>.root{margin-left:.277778em;margin-right:-.555556em}.katex .fontsize-ensurer.reset-size1.size1,.katex .sizing.reset-size1.size1{font-size:1em}.katex .fontsize-ensurer.reset-size1.size2,.katex .sizing.reset-size1.size2{font-size:1.2em}.katex .fontsize-ensurer.reset-size1.size3,.katex .sizing.reset-size1.size3{font-size:1.4em}.katex .fontsize-ensurer.reset-size1.size4,.katex .sizing.reset-size1.size4{font-size:1.6em}.katex .fontsize-ensurer.reset-size1.size5,.katex .sizing.reset-size1.size5{font-size:1.8em}.katex .fontsize-ensurer.reset-size1.size6,.katex .sizing.reset-size1.size6{font-size:2em}.katex .fontsize-ensurer.reset-size1.size7,.katex .sizing.reset-size1.size7{font-size:2.4em}.katex .fontsize-ensurer.reset-size1.size8,.katex .sizing.reset-size1.size8{font-size:2.88em}.katex .fontsize-ensurer.reset-size1.size9,.katex .sizing.reset-size1.size9{font-size:3.456em}.katex .fontsize-ensurer.reset-size1.size10,.katex .sizing.reset-size1.size10{font-size:4.148em}.katex .fontsize-ensurer.reset-size1.size11,.katex .sizing.reset-size1.size11{font-size:4.976em}.katex .fontsize-ensurer.reset-size2.size1,.katex .sizing.reset-size2.size1{font-size:.833333em}.katex .fontsize-ensurer.reset-size2.size2,.katex .sizing.reset-size2.size2{font-size:1em}.katex .fontsize-ensurer.reset-size2.size3,.katex .sizing.reset-size2.size3{font-size:1.16667em}.katex .fontsize-ensurer.reset-size2.size4,.katex .sizing.reset-size2.size4{font-size:1.33333em}.katex .fontsize-ensurer.reset-size2.size5,.katex .sizing.reset-size2.size5{font-size:1.5em}.katex .fontsize-ensurer.reset-size2.size6,.katex .sizing.reset-size2.size6{font-size:1.66667em}.katex .fontsize-ensurer.reset-size2.size7,.katex .sizing.reset-size2.size7{font-size:2em}.katex .fontsize-ensurer.reset-size2.size8,.katex .sizing.reset-size2.size8{font-size:2.4em}.katex .fontsize-ensurer.reset-size2.size9,.katex .sizing.reset-size2.size9{font-size:2.88em}.katex .fontsize-ensurer.reset-size2.size10,.katex .sizing.reset-size2.size10{font-size:3.45667em}.katex .fontsize-ensurer.reset-size2.size11,.katex .sizing.reset-size2.size11{font-size:4.14667em}.katex .fontsize-ensurer.reset-size3.size1,.katex .sizing.reset-size3.size1{font-size:.714286em}.katex .fontsize-ensurer.reset-size3.size2,.katex .sizing.reset-size3.size2{font-size:.857143em}.katex .fontsize-ensurer.reset-size3.size3,.katex .sizing.reset-size3.size3{font-size:1em}.katex .fontsize-ensurer.reset-size3.size4,.katex .sizing.reset-size3.size4{font-size:1.14286em}.katex .fontsize-ensurer.reset-size3.size5,.katex .sizing.reset-size3.size5{font-size:1.28571em}.katex .fontsize-ensurer.reset-size3.size6,.katex .sizing.reset-size3.size6{font-size:1.42857em}.katex .fontsize-ensurer.reset-size3.size7,.katex .sizing.reset-size3.size7{font-size:1.71429em}.katex .fontsize-ensurer.reset-size3.size8,.katex .sizing.reset-size3.size8{font-size:2.05714em}.katex .fontsize-ensurer.reset-size3.size9,.katex .sizing.reset-size3.size9{font-size:2.46857em}.katex .fontsize-ensurer.reset-size3.size10,.katex .sizing.reset-size3.size10{font-size:2.96286em}.katex .fontsize-ensurer.reset-size3.size11,.katex .sizing.reset-size3.size11{font-size:3.55429em}.katex .fontsize-ensurer.reset-size4.size1,.katex .sizing.reset-size4.size1{font-size:.625em}.katex .fontsize-ensurer.reset-size4.size2,.katex .sizing.reset-size4.size2{font-size:.75em}.katex .fontsize-ensurer.reset-size4.size3,.katex .sizing.reset-size4.size3{font-size:.875em}.katex .fontsize-ensurer.reset-size4.size4,.katex .sizing.reset-size4.size4{font-size:1em}.katex .fontsize-ensurer.reset-size4.size5,.katex .sizing.reset-size4.size5{font-size:1.125em}.katex .fontsize-ensurer.reset-size4.size6,.katex .sizing.reset-size4.size6{font-size:1.25em}.katex .fontsize-ensurer.reset-size4.size7,.katex .sizing.reset-size4.size7{font-size:1.5em}.katex .fontsize-ensurer.reset-size4.size8,.katex .sizing.reset-size4.size8{font-size:1.8em}.katex .fontsize-ensurer.reset-size4.size9,.katex .sizing.reset-size4.size9{font-size:2.16em}.katex .fontsize-ensurer.reset-size4.size10,.katex .sizing.reset-size4.size10{font-size:2.5925em}.katex .fontsize-ensurer.reset-size4.size11,.katex .sizing.reset-size4.size11{font-size:3.11em}.katex .fontsize-ensurer.reset-size5.size1,.katex .sizing.reset-size5.size1{font-size:.555556em}.katex .fontsize-ensurer.reset-size5.size2,.katex .sizing.reset-size5.size2{font-size:.666667em}.katex .fontsize-ensurer.reset-size5.size3,.katex .sizing.reset-size5.size3{font-size:.777778em}.katex .fontsize-ensurer.reset-size5.size4,.katex .sizing.reset-size5.size4{font-size:.888889em}.katex .fontsize-ensurer.reset-size5.size5,.katex .sizing.reset-size5.size5{font-size:1em}.katex .fontsize-ensurer.reset-size5.size6,.katex .sizing.reset-size5.size6{font-size:1.11111em}.katex .fontsize-ensurer.reset-size5.size7,.katex .sizing.reset-size5.size7{font-size:1.33333em}.katex .fontsize-ensurer.reset-size5.size8,.katex .sizing.reset-size5.size8{font-size:1.6em}.katex .fontsize-ensurer.reset-size5.size9,.katex .sizing.reset-size5.size9{font-size:1.92em}.katex .fontsize-ensurer.reset-size5.size10,.katex .sizing.reset-size5.size10{font-size:2.30444em}.katex .fontsize-ensurer.reset-size5.size11,.katex .sizing.reset-size5.size11{font-size:2.76444em}.katex .fontsize-ensurer.reset-size6.size1,.katex .sizing.reset-size6.size1{font-size:.5em}.katex .fontsize-ensurer.reset-size6.size2,.katex .sizing.reset-size6.size2{font-size:.6em}.katex .fontsize-ensurer.reset-size6.size3,.katex .sizing.reset-size6.size3{font-size:.7em}.katex .fontsize-ensurer.reset-size6.size4,.katex .sizing.reset-size6.size4{font-size:.8em}.katex .fontsize-ensurer.reset-size6.size5,.katex .sizing.reset-size6.size5{font-size:.9em}.katex .fontsize-ensurer.reset-size6.size6,.katex .sizing.reset-size6.size6{font-size:1em}.katex .fontsize-ensurer.reset-size6.size7,.katex .sizing.reset-size6.size7{font-size:1.2em}.katex .fontsize-ensurer.reset-size6.size8,.katex .sizing.reset-size6.size8{font-size:1.44em}.katex .fontsize-ensurer.reset-size6.size9,.katex .sizing.reset-size6.size9{font-size:1.728em}.katex .fontsize-ensurer.reset-size6.size10,.katex .sizing.reset-size6.size10{font-size:2.074em}.katex .fontsize-ensurer.reset-size6.size11,.katex .sizing.reset-size6.size11{font-size:2.488em}.katex .fontsize-ensurer.reset-size7.size1,.katex .sizing.reset-size7.size1{font-size:.416667em}.katex .fontsize-ensurer.reset-size7.size2,.katex .sizing.reset-size7.size2{font-size:.5em}.katex .fontsize-ensurer.reset-size7.size3,.katex .sizing.reset-size7.size3{font-size:.583333em}.katex .fontsize-ensurer.reset-size7.size4,.katex .sizing.reset-size7.size4{font-size:.666667em}.katex .fontsize-ensurer.reset-size7.size5,.katex .sizing.reset-size7.size5{font-size:.75em}.katex .fontsize-ensurer.reset-size7.size6,.katex .sizing.reset-size7.size6{font-size:.833333em}.katex .fontsize-ensurer.reset-size7.size7,.katex .sizing.reset-size7.size7{font-size:1em}.katex .fontsize-ensurer.reset-size7.size8,.katex .sizing.reset-size7.size8{font-size:1.2em}.katex .fontsize-ensurer.reset-size7.size9,.katex .sizing.reset-size7.size9{font-size:1.44em}.katex .fontsize-ensurer.reset-size7.size10,.katex .sizing.reset-size7.size10{font-size:1.72833em}.katex .fontsize-ensurer.reset-size7.size11,.katex .sizing.reset-size7.size11{font-size:2.07333em}.katex .fontsize-ensurer.reset-size8.size1,.katex .sizing.reset-size8.size1{font-size:.347222em}.katex .fontsize-ensurer.reset-size8.size2,.katex .sizing.reset-size8.size2{font-size:.416667em}.katex .fontsize-ensurer.reset-size8.size3,.katex .sizing.reset-size8.size3{font-size:.486111em}.katex .fontsize-ensurer.reset-size8.size4,.katex .sizing.reset-size8.size4{font-size:.555556em}.katex .fontsize-ensurer.reset-size8.size5,.katex .sizing.reset-size8.size5{font-size:.625em}.katex .fontsize-ensurer.reset-size8.size6,.katex .sizing.reset-size8.size6{font-size:.694444em}.katex .fontsize-ensurer.reset-size8.size7,.katex .sizing.reset-size8.size7{font-size:.833333em}.katex .fontsize-ensurer.reset-size8.size8,.katex .sizing.reset-size8.size8{font-size:1em}.katex .fontsize-ensurer.reset-size8.size9,.katex .sizing.reset-size8.size9{font-size:1.2em}.katex .fontsize-ensurer.reset-size8.size10,.katex .sizing.reset-size8.size10{font-size:1.44028em}.katex .fontsize-ensurer.reset-size8.size11,.katex .sizing.reset-size8.size11{font-size:1.72778em}.katex .fontsize-ensurer.reset-size9.size1,.katex .sizing.reset-size9.size1{font-size:.289352em}.katex .fontsize-ensurer.reset-size9.size2,.katex .sizing.reset-size9.size2{font-size:.347222em}.katex .fontsize-ensurer.reset-size9.size3,.katex .sizing.reset-size9.size3{font-size:.405093em}.katex .fontsize-ensurer.reset-size9.size4,.katex .sizing.reset-size9.size4{font-size:.462963em}.katex .fontsize-ensurer.reset-size9.size5,.katex .sizing.reset-size9.size5{font-size:.520833em}.katex .fontsize-ensurer.reset-size9.size6,.katex .sizing.reset-size9.size6{font-size:.578704em}.katex .fontsize-ensurer.reset-size9.size7,.katex .sizing.reset-size9.size7{font-size:.694444em}.katex .fontsize-ensurer.reset-size9.size8,.katex .sizing.reset-size9.size8{font-size:.833333em}.katex .fontsize-ensurer.reset-size9.size9,.katex .sizing.reset-size9.size9{font-size:1em}.katex .fontsize-ensurer.reset-size9.size10,.katex .sizing.reset-size9.size10{font-size:1.20023em}.katex .fontsize-ensurer.reset-size9.size11,.katex .sizing.reset-size9.size11{font-size:1.43981em}.katex .fontsize-ensurer.reset-size10.size1,.katex .sizing.reset-size10.size1{font-size:.24108em}.katex .fontsize-ensurer.reset-size10.size2,.katex .sizing.reset-size10.size2{font-size:.289296em}.katex .fontsize-ensurer.reset-size10.size3,.katex .sizing.reset-size10.size3{font-size:.337512em}.katex .fontsize-ensurer.reset-size10.size4,.katex .sizing.reset-size10.size4{font-size:.385728em}.katex .fontsize-ensurer.reset-size10.size5,.katex .sizing.reset-size10.size5{font-size:.433944em}.katex .fontsize-ensurer.reset-size10.size6,.katex .sizing.reset-size10.size6{font-size:.48216em}.katex .fontsize-ensurer.reset-size10.size7,.katex .sizing.reset-size10.size7{font-size:.578592em}.katex .fontsize-ensurer.reset-size10.size8,.katex .sizing.reset-size10.size8{font-size:.694311em}.katex .fontsize-ensurer.reset-size10.size9,.katex .sizing.reset-size10.size9{font-size:.833173em}.katex .fontsize-ensurer.reset-size10.size10,.katex .sizing.reset-size10.size10{font-size:1em}.katex .fontsize-ensurer.reset-size10.size11,.katex .sizing.reset-size10.size11{font-size:1.19961em}.katex .fontsize-ensurer.reset-size11.size1,.katex .sizing.reset-size11.size1{font-size:.200965em}.katex .fontsize-ensurer.reset-size11.size2,.katex .sizing.reset-size11.size2{font-size:.241158em}.katex .fontsize-ensurer.reset-size11.size3,.katex .sizing.reset-size11.size3{font-size:.281351em}.katex .fontsize-ensurer.reset-size11.size4,.katex .sizing.reset-size11.size4{font-size:.321543em}.katex .fontsize-ensurer.reset-size11.size5,.katex .sizing.reset-size11.size5{font-size:.361736em}.katex .fontsize-ensurer.reset-size11.size6,.katex .sizing.reset-size11.size6{font-size:.401929em}.katex .fontsize-ensurer.reset-size11.size7,.katex .sizing.reset-size11.size7{font-size:.482315em}.katex .fontsize-ensurer.reset-size11.size8,.katex .sizing.reset-size11.size8{font-size:.578778em}.katex .fontsize-ensurer.reset-size11.size9,.katex .sizing.reset-size11.size9{font-size:.694534em}.katex .fontsize-ensurer.reset-size11.size10,.katex .sizing.reset-size11.size10{font-size:.833601em}.katex .fontsize-ensurer.reset-size11.size11,.katex .sizing.reset-size11.size11{font-size:1em}.katex .delimsizing.size1{font-family:KaTeX_Size1}.katex .delimsizing.size2{font-family:KaTeX_Size2}.katex .delimsizing.size3{font-family:KaTeX_Size3}.katex .delimsizing.size4{font-family:KaTeX_Size4}.katex .delimsizing.mult .delim-size1>span{font-family:KaTeX_Size1}.katex .delimsizing.mult .delim-size4>span{font-family:KaTeX_Size4}.katex .nulldelimiter{width:.12em;display:inline-block}.katex .delimcenter,.katex .op-symbol{position:relative}.katex .op-symbol.small-op{font-family:KaTeX_Size1}.katex .op-symbol.large-op{font-family:KaTeX_Size2}.katex .accent>.vlist-t,.katex .op-limits>.vlist-t{text-align:center}.katex .accent .accent-body{position:relative}.katex .accent .accent-body:not(.accent-full){width:0}.katex .overlay{display:block}.katex .mtable .vertical-separator{min-width:1px;display:inline-block}.katex .mtable .arraycolsep{display:inline-block}.katex .mtable .col-align-c>.vlist-t{text-align:center}.katex .mtable .col-align-l>.vlist-t{text-align:left}.katex .mtable .col-align-r>.vlist-t{text-align:right}.katex .svg-align{text-align:left}.katex svg{fill:currentColor;stroke:currentColor;height:inherit;width:100%;display:block;position:absolute}.katex svg path{stroke:none}.katex svg{fill-rule:nonzero;fill-opacity:1;stroke-width:1px;stroke-linecap:butt;stroke-linejoin:miter;stroke-miterlimit:4;stroke-dasharray:none;stroke-dashoffset:0;stroke-opacity:1}.katex img{border-style:none;min-width:0;max-width:none;min-height:0;max-height:none}.katex .stretchy{width:100%;display:block;position:relative;overflow:hidden}.katex .stretchy:after,.katex .stretchy:before{content:""}.katex .hide-tail{width:100%;position:relative;overflow:hidden}.katex .halfarrow-left{width:50.2%;position:absolute;left:0;overflow:hidden}.katex .halfarrow-right{width:50.2%;position:absolute;right:0;overflow:hidden}.katex .brace-left{width:25.1%;position:absolute;left:0;overflow:hidden}.katex .brace-center{width:50%;position:absolute;left:25%;overflow:hidden}.katex .brace-right{width:25.1%;position:absolute;right:0;overflow:hidden}.katex .x-arrow-pad{padding:0 .5em}.katex .cd-arrow-pad{padding:0 .55556em 0 .27778em}.katex .mover,.katex .munder,.katex .x-arrow{text-align:center}.katex .boxpad{padding:0 .3em}.katex .fbox,.katex .fcolorbox{box-sizing:border-box;border:.04em solid}.katex .cancel-pad{padding:0 .2em}.katex .cancel-lap{margin-left:-.2em;margin-right:-.2em}.katex .sout{border-bottom-style:solid;border-bottom-width:.08em}.katex .angl{box-sizing:border-box;border-top:.049em solid;border-right:.049em solid;margin-right:.03889em}.katex .anglpad{padding:0 .03889em}.katex .eqn-num:before{content:"(" counter(katexEqnNo) ")";counter-increment:katexEqnNo}.katex .mml-eqn-num:before{content:"(" counter(mmlEqnNo) ")";counter-increment:mmlEqnNo}.katex .mtr-glue{width:50%}.katex .cd-vert-arrow{display:inline-block;position:relative}.katex .cd-label-left{text-align:left;display:inline-block;position:absolute;right:calc(50% + .3em)}.katex .cd-label-right{text-align:right;display:inline-block;position:absolute;left:calc(50% + .3em)}.katex-display{text-align:center;margin:1em 0;display:block}.katex-display>.katex{text-align:center;white-space:nowrap;display:block}.katex-display>.katex>.katex-html{display:block;position:relative}.katex-display>.katex>.katex-html>.tag{position:absolute;right:0}.katex-display.leqno>.katex>.katex-html>.tag{left:0;right:auto}.katex-display.fleqn>.katex{text-align:left;padding-left:2em}body{counter-reset:katexEqnNo mmlEqnNo}