:root{--jade-700: #0f7a4f;--jade-600: #14a066;--jade-500: #1ec27c;--jade-400: #3ee39a;--jade-300: #8ff2c3;--jade-100: #e2fbef;--lime-500: #b8f23c;--lime-400: #d3ff6a;--sun-500: #ffb300;--sun-400: #ffcf4d;--sun-100: #fff4d6;--lantern-500: #ff4d5a;--lantern-400: #ff7a83;--blossom-500: #ff7bd4;--blossom-300: #ffb8e8;--sky-500: #2f8bff;--sky-300: #9ac8ff;--grape-500: #8b5cf6;--night-950: #071a14;--night-900: #0b2a20;--night-800: #10382b;--night-700: #164a39;--paper: #fbfdf8;--paper-2: #f0f8f1;--ink: #0e1f18;--ink-2: #3f5a4d;--ink-3: #5b7466;--tone1: #2f8bff;--tone2: #14a066;--tone3: #8b5cf6;--tone4: #ff4d5a;--tone5: #8a9a92;--bg: var(--paper);--bg-elev: #ffffff;--bg-soft: var(--paper-2);--fg: var(--ink);--fg-muted: var(--ink-2);--fg-faint: var(--ink-3);--line: rgba(14, 31, 24, .1);--line-strong: rgba(14, 31, 24, .18);--accent: var(--jade-600);--accent-text: var(--jade-700);--accent-strong: var(--jade-700);--accent-soft: var(--jade-100);--accent-glow: rgba(30, 194, 124, .35);--gold: var(--sun-500);--gold-soft: var(--sun-100);--danger: var(--lantern-500);--hero: linear-gradient(135deg, #14a066 0%, #0f7a4f 45%, #0b2a20 100%);--hero-accent: radial-gradient(circle at 80% 20%, rgba(211,255,106,.35), transparent 45%), radial-gradient(circle at 15% 90%, rgba(47,139,255,.35), transparent 40%);--btn-shadow: 0 4px 0 0 rgba(14,31,24,.16);--btn-shadow-accent: 0 4px 0 0 var(--jade-700);--btn-shadow-gold: 0 4px 0 0 #c98a00;--font-body: "Nunito", "Manrope", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;--font-hanzi: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;--font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;--radius: 18px;--radius-lg: 26px;--radius-xl: 34px;--shadow-sm: 0 1px 2px rgba(14,31,24,.05), 0 2px 8px rgba(14,31,24,.06);--shadow-md: 0 12px 34px -12px rgba(14,31,24,.22);--shadow-glow: 0 10px 40px -10px var(--accent-glow);--ease: cubic-bezier(.2,.8,.2,1);--bounce: cubic-bezier(.34,1.56,.64,1);--gutter: clamp(1rem, 4vw, 2rem);--container: 1080px}@media (prefers-color-scheme: dark){:root:not([data-theme=light]){--bg: var(--night-950);--bg-elev: var(--night-900);--bg-soft: var(--night-800);--fg: #eefbf3;--fg-muted: #b5d4c3;--fg-faint: #7fa08f;--line: rgba(255,255,255,.09);--line-strong: rgba(255,255,255,.18);--accent: var(--jade-500);--accent-text: var(--jade-400);--accent-strong: var(--jade-400);--accent-soft: rgba(30,194,124,.16);--gold: var(--sun-400);--gold-soft: rgba(255,207,77,.16);--hero: linear-gradient(135deg, #14a066 0%, #0f5f40 40%, #0b2a20 100%);--btn-shadow: 0 4px 0 0 rgba(0,0,0,.45);--btn-shadow-accent: 0 4px 0 0 #0c6b45;--btn-shadow-gold: 0 4px 0 0 #b07a00;--shadow-md: 0 12px 34px -12px rgba(0,0,0,.6)}}:root[data-theme=dark]{--bg: var(--night-950);--bg-elev: var(--night-900);--bg-soft: var(--night-800);--fg: #eefbf3;--fg-muted: #b5d4c3;--fg-faint: #7fa08f;--line: rgba(255,255,255,.09);--line-strong: rgba(255,255,255,.18);--accent: var(--jade-500);--accent-text: var(--jade-400);--accent-strong: var(--jade-400);--accent-soft: rgba(30,194,124,.16);--gold: var(--sun-400);--gold-soft: rgba(255,207,77,.16);--hero: linear-gradient(135deg, #14a066 0%, #0f5f40 40%, #0b2a20 100%);--btn-shadow: 0 4px 0 0 rgba(0,0,0,.45);--btn-shadow-accent: 0 4px 0 0 #0c6b45;--btn-shadow-gold: 0 4px 0 0 #b07a00;--shadow-md: 0 12px 34px -12px rgba(0,0,0,.6)}*,*:before,*:after{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;font-family:var(--font-body);font-size:1.02rem;line-height:1.55;color:var(--fg);background:var(--bg);-webkit-font-smoothing:antialiased;position:relative;min-height:100vh}body:before,body:after{content:"";position:fixed;z-index:-1;border-radius:50%;filter:blur(70px);opacity:.55;pointer-events:none}body:before{width:46vw;height:46vw;top:-12vw;right:-10vw;background:radial-gradient(circle,rgba(211,255,106,.55),rgba(30,194,124,.25) 60%,transparent 70%)}body:after{width:40vw;height:40vw;bottom:-14vw;left:-12vw;background:radial-gradient(circle,rgba(255,123,212,.35),rgba(47,139,255,.25) 60%,transparent 70%)}a{color:inherit;text-decoration:none}button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}input,select,textarea{font:inherit;color:inherit}h1,h2,h3,h4{margin:0;line-height:1.12;letter-spacing:-.015em;font-weight:800}p{margin:0}ul{margin:0;padding:0;list-style:none}:focus-visible{outline:3px solid var(--sky-500);outline-offset:3px;border-radius:6px}.hz{font-family:var(--font-hanzi);font-weight:700}.muted{color:var(--fg-muted)}.faint{color:var(--fg-faint)}.small{font-size:.875rem}.mono{font-family:var(--font-mono)}.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}.container{width:min(100% - 2 * var(--gutter),var(--container));margin-inline:auto}.header{position:sticky;top:0;z-index:20;background:color-mix(in srgb,var(--bg) 82%,transparent);backdrop-filter:blur(14px) saturate(140%);border-bottom:1px solid var(--line)}.header .container{display:flex;align-items:center;gap:1rem;min-height:68px}.brand{display:flex;align-items:center;gap:.75rem;font-weight:900;letter-spacing:-.01em;font-size:1.05rem;white-space:nowrap}.brand .mark{width:42px;height:42px;border-radius:14px;background:linear-gradient(140deg,var(--jade-400),var(--jade-700));color:#fff;display:grid;place-items:center;font-family:var(--font-hanzi);font-size:1.45rem;box-shadow:0 6px 18px -6px var(--accent-glow),inset 0 -3px #0000002e;transform:rotate(-4deg);transition:transform .35s var(--bounce)}.brand:hover .mark{transform:rotate(6deg) scale(1.06)}.brand small{display:block;font-size:.68rem;font-weight:800;color:var(--accent-text);letter-spacing:.14em;text-transform:uppercase}.nav{margin-left:auto;display:flex;gap:.2rem;overflow-x:auto;scrollbar-width:none}.nav::-webkit-scrollbar{display:none}.nav a{display:inline-flex;align-items:center;min-height:44px;padding:.5rem .8rem;border-radius:999px;font-size:.86rem;font-weight:800;color:var(--fg-muted);white-space:nowrap;transition:background .2s,color .2s,transform .2s var(--bounce)}.nav a:hover{background:var(--bg-soft);color:var(--fg);transform:translateY(-1px)}.nav a[aria-current=page]{background:var(--accent-text);color:var(--bg-elev);box-shadow:0 6px 16px -6px var(--accent-glow)}main{padding-block:clamp(1.5rem,4vw,3rem);min-height:70vh}.stack{display:grid;gap:1rem}.stack-lg{display:grid;gap:1.75rem}.grid{display:grid;gap:1rem}.grid-2{grid-template-columns:repeat(auto-fit,minmax(280px,1fr))}.grid-3{grid-template-columns:repeat(auto-fit,minmax(200px,1fr))}.grid-3:has(>.stat){grid-template-columns:repeat(auto-fit,minmax(150px,1fr))}.grid-tiles{grid-template-columns:repeat(auto-fill,minmax(150px,1fr))}.row{display:flex;flex-wrap:wrap;gap:.6rem;align-items:center}.between{justify-content:space-between}.eyebrow{display:inline-flex;align-items:center;gap:.45rem;font-size:.72rem;font-weight:900;letter-spacing:.16em;text-transform:uppercase;color:var(--accent-text)}.h1{font-size:clamp(2rem,1.3rem + 2.8vw,3.2rem);letter-spacing:-.03em;line-height:1.02;font-weight:900}.h2{font-size:clamp(1.45rem,1.1rem + 1.2vw,2rem);font-weight:900}.h3{font-size:1.2rem;font-weight:800}.lead{font-size:1.12rem;color:var(--fg-muted);max-width:62ch}.prose{max-width:70ch}.prose p+p,.prose ul+p,.prose p+ul{margin-top:.9rem}.prose ul{list-style:disc;padding-left:1.2rem}.prose li+li{margin-top:.35rem}.prose h2{margin-top:2rem;margin-bottom:.6rem}.prose h3{margin-top:1.4rem;margin-bottom:.4rem}hr{border:0;border-top:1px solid var(--line);margin:1.5rem 0}.card{background:var(--bg-elev);border:1px solid var(--line);border-radius:var(--radius-lg);padding:clamp(1.1rem,3vw,1.6rem);box-shadow:var(--shadow-sm);position:relative}.card-soft{background:var(--bg-soft);border-color:transparent;box-shadow:none}.card-accent{background:var(--hero);color:#fff;border:0;overflow:hidden;box-shadow:var(--shadow-glow)}.card-accent:before{content:"";position:absolute;inset:0;background:var(--hero-accent);pointer-events:none}.card-accent>*{position:relative}.card-accent .muted,.card-accent .faint,.card-accent .lead{color:#ffffffe0}.card-accent .eyebrow{color:var(--lime-400)}.card-accent .chip{background:#ffffff24;color:#fff;border-color:#ffffff38}.card-accent .chip .hz{color:#fff}.card-accent .chip-gold{background:#ffcf4d38}.tile{background:var(--bg-elev);border:1px solid var(--line);border-radius:var(--radius);padding:1rem;display:grid;gap:.25rem;text-align:left;transition:transform .25s var(--bounce),box-shadow .25s var(--ease),border-color .25s}.tile:hover{transform:translateY(-4px) scale(1.01);box-shadow:var(--shadow-md);border-color:var(--accent)}.tile .hz{font-size:2.4rem;line-height:1.1}.stat{display:grid;gap:.2rem}.stat b{font-size:2rem;font-weight:900;letter-spacing:-.02em;line-height:1;background:linear-gradient(120deg,var(--accent-strong),var(--sky-500));-webkit-background-clip:text;background-clip:text;color:transparent}.stat span{font-size:.8rem;color:var(--fg-muted);font-weight:700}.btn{display:inline-flex;align-items:center;justify-content:center;gap:.5rem;padding:.8rem 1.3rem;border-radius:999px;font-weight:900;font-size:.95rem;line-height:1;border:1px solid var(--line-strong);background:var(--bg-elev);color:var(--fg);box-shadow:var(--btn-shadow);transition:transform .12s var(--ease),box-shadow .12s var(--ease),background .2s,filter .2s;white-space:nowrap;letter-spacing:.01em}.btn:hover{filter:brightness(1.04);transform:translateY(-1px)}.btn:active{transform:translateY(3px);box-shadow:0 1px #0e1f1829}.btn:disabled{opacity:.5;cursor:not-allowed;transform:none}.btn-primary{background:linear-gradient(180deg,var(--jade-500),var(--jade-600));color:#fff;border-color:transparent;box-shadow:var(--btn-shadow-accent)}.btn-primary:active{box-shadow:0 1px 0 0 var(--jade-700)}.btn-gold{background:linear-gradient(180deg,var(--sun-400),var(--sun-500));color:#2a1d00;border-color:transparent;box-shadow:var(--btn-shadow-gold)}.btn-gold:active{box-shadow:0 1px #c98a00}.btn-ghost{background:transparent;box-shadow:none;border-color:transparent}.btn-ghost:active{transform:translateY(1px)}.btn-sm{padding:.5rem .9rem;font-size:.82rem;box-shadow:0 2px #0e1f1824}.btn-sm.btn-primary{box-shadow:0 2px 0 0 var(--jade-700)}.btn-lg{padding:1.05rem 1.8rem;font-size:1.1rem}.btn-icon{width:42px;height:42px;padding:0;border-radius:50%;font-size:1.1rem}.btn-block{width:100%}.chip{display:inline-flex;align-items:center;gap:.4rem;padding:.35rem .75rem;border-radius:999px;background:var(--bg-soft);font-size:.82rem;font-weight:800;color:var(--fg-muted);border:1px solid var(--line)}.chip .hz{font-size:1.05rem;color:var(--fg)}.chip-accent{background:var(--accent-soft);color:var(--accent-strong);border-color:transparent}.chip-gold{background:var(--gold-soft);color:var(--fg);border-color:transparent}button.chip:hover{border-color:var(--accent);transform:translateY(-1px)}.field{display:grid;gap:.35rem}.field label{font-size:.8rem;font-weight:900;color:var(--fg-muted);letter-spacing:.02em}.input,textarea.input,select.input{width:100%;padding:.7rem .95rem;border-radius:14px;border:2px solid var(--line-strong);background:var(--bg-elev);color:var(--fg);transition:border-color .2s,box-shadow .2s}.input:focus{border-color:var(--accent);outline:none;box-shadow:0 0 0 4px var(--accent-soft)}textarea.input{min-height:84px;resize:vertical;line-height:1.5}.table{width:100%;border-collapse:collapse;font-size:.93rem}.table th,.table td{text-align:left;padding:.65rem .5rem;border-bottom:1px solid var(--line);vertical-align:middle}.table th{font-size:.72rem;letter-spacing:.12em;text-transform:uppercase;color:var(--fg-faint);font-weight:900}.table .input{padding:.45rem .7rem}.table tr:hover td{background:var(--bg-soft)}#app{min-height:85vh}.table-scroll{overflow-x:auto;-webkit-overflow-scrolling:touch;max-width:100%}.show-sm{display:none}.t1{color:var(--tone1)}.t2{color:var(--tone2)}.t3{color:var(--tone3)}.t4{color:var(--tone4)}.t5{color:var(--tone5)}.py{font-weight:800;letter-spacing:.01em}.lesson-top{position:sticky;top:68px;z-index:10;background:color-mix(in srgb,var(--bg) 88%,transparent);backdrop-filter:blur(10px);padding:.8rem 0;border-bottom:1px solid var(--line)}.timer{display:flex;align-items:center;gap:1rem}.timer .clock{font-family:var(--font-mono);font-size:1.35rem;font-weight:800;min-width:5ch;padding:.25rem .6rem;border-radius:12px;background:var(--accent-soft);color:var(--accent-strong)}.timer .clock.over{color:#fff;background:var(--danger)}.segments{display:flex;gap:.4rem;flex:1}.segments button{flex:1;height:12px;border-radius:999px;background:var(--bg-soft);border:1px solid var(--line);position:relative;transition:background .3s,transform .2s var(--bounce);overflow:visible}.segments button:hover{transform:scaleY(1.3)}.segments button.done{background:linear-gradient(90deg,var(--jade-400),var(--jade-600));border-color:transparent}.segments button.active{background:linear-gradient(90deg,var(--sun-400),var(--sun-500));border-color:transparent;box-shadow:0 0 0 4px var(--gold-soft)}.segments button span{position:absolute;top:16px;left:0;right:0;font-size:.66rem;font-weight:900;color:var(--fg-faint);text-align:center;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;letter-spacing:.04em}.segments button.active span{color:var(--fg)}.seg-head{display:flex;align-items:baseline;justify-content:space-between;gap:1rem;margin-top:1.6rem}.big-hz{font-family:var(--font-hanzi);font-weight:700;font-size:clamp(4.5rem,13vw,7.5rem);line-height:1;text-align:center;background:linear-gradient(160deg,var(--fg),var(--accent-strong));-webkit-background-clip:text;background-clip:text;color:transparent}.mid-hz{font-family:var(--font-hanzi);font-weight:700;font-size:clamp(1.8rem,5vw,2.6rem);line-height:1.25}.scene{background:linear-gradient(135deg,var(--gold-soft),var(--accent-soft));border-left:5px solid var(--gold);padding:1rem 1.15rem;border-radius:6px var(--radius) var(--radius) 6px;line-height:1.65;font-size:1.05rem;font-weight:600}.props{display:flex;flex-wrap:wrap;gap:.4rem}.flash{min-height:240px;display:grid;place-items:center;text-align:center;gap:.6rem;cursor:pointer;background:linear-gradient(160deg,var(--bg-elev),var(--bg-soft));border:2px dashed var(--line-strong);transition:border-color .2s,transform .2s var(--bounce);animation:pop-in .35s var(--bounce)}.flash:hover{border-color:var(--accent);transform:translateY(-2px)}.flash .answer{display:grid;gap:.3rem;animation:pop-in .3s var(--bounce)}.grades{display:grid;grid-template-columns:repeat(4,1fr);gap:.5rem}.grades .btn{padding:.8rem .4rem;font-size:.88rem}.g-again{border-color:var(--danger);color:var(--danger);box-shadow:0 4px 0 0 var(--danger);background:var(--bg-elev)}.g-hard{border-color:var(--sun-500);color:#8a5a00;box-shadow:0 4px 0 0 var(--sun-500)}.g-good{border-color:var(--accent);color:var(--accent-strong);box-shadow:0 4px 0 0 var(--accent)}.g-easy{background:linear-gradient(180deg,var(--jade-500),var(--jade-600));color:#fff;border-color:transparent;box-shadow:var(--btn-shadow-accent)}.quiz-opt{display:block;width:100%;text-align:left;padding:.95rem 1.1rem;border:2px solid var(--line-strong);border-radius:16px;background:var(--bg-elev);font-weight:800;box-shadow:var(--btn-shadow);transition:transform .12s,box-shadow .12s,border-color .2s,background .2s}.quiz-opt:hover{border-color:var(--sky-500);transform:translateY(-1px)}.quiz-opt:active{transform:translateY(3px);box-shadow:none}.quiz-opt.right{background:var(--accent-soft);border-color:var(--accent);color:var(--accent-strong);animation:pop-in .35s var(--bounce)}.quiz-opt.wrong{background:color-mix(in srgb,var(--danger) 14%,var(--bg-elev));border-color:var(--danger);animation:shake .4s var(--ease)}.sentence{display:grid;gap:.35rem;padding:1.1rem;border:1px solid var(--line);border-radius:var(--radius);background:var(--bg-elev);border-left:5px solid var(--sky-500)}.sentence .en{color:var(--fg-muted)}.sentence .en.hidden{filter:blur(6px);cursor:pointer}.done-banner{text-align:center;display:grid;gap:.9rem;padding:2.2rem 1rem;background:var(--hero);color:#fff;border:0;overflow:hidden}.done-banner:before{content:"";position:absolute;inset:0;background:var(--hero-accent)}.done-banner>*{position:relative}.done-banner .big-hz{font-size:5rem;background:linear-gradient(160deg,#fff,var(--lime-400));-webkit-background-clip:text;background-clip:text;color:transparent;animation:pop-in .6s var(--bounce)}.done-banner .muted{color:#ffffffd9}.done-banner .btn{box-shadow:0 4px #00000040}.progress-ring{--p: 0;width:132px;height:132px;border-radius:50%;background:conic-gradient(var(--lime-400) calc(var(--p) * 1%),rgba(255,255,255,.18) 0);display:grid;place-items:center;margin-inline:auto;box-shadow:0 0 0 6px #ffffff14}.progress-ring div{width:104px;height:104px;border-radius:50%;background:#071a148c;display:grid;place-items:center;font-weight:900;font-size:1.5rem;color:#fff}.heatmap{display:grid;grid-template-columns:repeat(13,1fr);gap:5px}.heatmap i{display:block;aspect-ratio:1;border-radius:6px;background:var(--bg-soft);border:1px solid var(--line);transition:transform .2s var(--bounce)}.heatmap i:hover{transform:scale(1.25)}.heatmap i.on{background:linear-gradient(160deg,var(--jade-400),var(--jade-600));border-color:transparent}.heatmap i.missed{background:color-mix(in srgb,var(--danger) 30%,transparent)}.heatmap i.today{outline:3px solid var(--gold);outline-offset:1px}.heatmap i.future{opacity:.35}.forest{display:flex;align-items:flex-end;gap:2px;height:56px;overflow:hidden;padding:0 .25rem}.forest svg{width:22px;height:44px;flex:0 0 auto;transform-origin:bottom center;animation:grow .6s var(--bounce) both}.forest svg:nth-child(3n){height:52px}.forest svg:nth-child(5n){height:36px}.streak{display:inline-flex;align-items:center;gap:.35rem;padding:.35rem .8rem;border-radius:999px;background:linear-gradient(180deg,var(--sun-400),var(--sun-500));color:#2a1d00;font-weight:900;box-shadow:0 3px #c98a00}.streak .fire{font-size:1.1rem;animation:flicker 1.6s ease-in-out infinite}dialog{border:0;border-radius:var(--radius-xl);padding:0;background:var(--bg-elev);color:var(--fg);width:min(92vw,560px);box-shadow:var(--shadow-md);animation:pop-in .3s var(--bounce)}dialog::backdrop{background:#071a1499;backdrop-filter:blur(6px)}dialog .inner{padding:1.6rem;display:grid;gap:1rem;max-height:86vh;overflow:auto}.toast{position:fixed;bottom:1.2rem;left:50%;transform:translate(-50%) translateY(20px);background:var(--night-900);color:#fff;padding:.8rem 1.2rem;border-radius:999px;font-weight:800;box-shadow:var(--shadow-md);z-index:50;opacity:0;transition:opacity .25s,transform .3s var(--bounce);pointer-events:none;border:1px solid rgba(255,255,255,.12)}.toast.show{opacity:1;transform:translate(-50%) translateY(0)}footer{border-top:1px solid var(--line);padding:1.5rem 0 2.5rem;color:var(--fg-faint);font-size:.85rem}footer a{color:var(--fg-muted);text-decoration:underline;text-underline-offset:2px}.asr{color:var(--fg-muted);margin-left:.4rem;font-weight:700}.asr .hz{color:var(--fg);font-size:1.05rem}audio.mine{max-width:220px}.chat{display:grid;gap:.75rem;max-height:58vh;overflow-y:auto;padding:.75rem;background:linear-gradient(180deg,var(--bg-soft),var(--bg-elev));border-radius:var(--radius-lg);border:1px solid var(--line)}.msg{max-width:88%;padding:.9rem 1.1rem;border-radius:20px;display:grid;gap:.3rem;animation:pop-in .3s var(--bounce)}.msg.me{justify-self:end;background:linear-gradient(135deg,var(--sky-500),var(--grape-500));color:#fff;border-bottom-right-radius:6px;font-size:1.15rem;box-shadow:0 8px 20px -10px #2f8bff99}.msg.tutor{justify-self:start;background:var(--bg-elev);border:1px solid var(--line);border-bottom-left-radius:6px;box-shadow:var(--shadow-sm)}.msg .zh{font-size:1.4rem;line-height:1.4}.msg .fix{color:var(--danger);font-weight:700}.msg .fix.ok{color:var(--accent-strong)}.msg .en.hidden{filter:blur(6px);cursor:pointer}.composer{display:flex;gap:.5rem;align-items:center}.composer .input{flex:1;font-size:1.1rem}.hw-box{width:260px;height:260px;border:2px solid var(--line-strong);border-radius:var(--radius);background:var(--bg-elev);background-image:linear-gradient(var(--line) 1px,transparent 1px),linear-gradient(90deg,var(--line) 1px,transparent 1px);background-size:50% 50%;background-position:center;display:grid;place-items:center;touch-action:none}.quiz-opt.hz{font-family:var(--font-hanzi)}@keyframes pop-in{0%{transform:scale(.94);opacity:0}to{transform:scale(1);opacity:1}}@keyframes shake{0%,to{transform:translate(0)}25%{transform:translate(-6px)}75%{transform:translate(6px)}}@keyframes grow{0%{transform:scaleY(0)}to{transform:scaleY(1)}}@keyframes flicker{0%,to{transform:scale(1) rotate(-3deg)}50%{transform:scale(1.15) rotate(4deg)}}.card-accent .h1{animation:pop-in .5s var(--bounce)}.confetti{position:fixed;inset:0;pointer-events:none;z-index:60}@media (prefers-reduced-motion: reduce){*,*:before,*:after{animation:none!important;transition:none!important}}@media (max-width: 640px){.header .container{flex-wrap:wrap;min-height:58px;padding-block:.5rem}.nav{margin-left:0;width:100%}.grades .btn{font-size:.78rem}.segments button span{display:none}.lesson-top{top:0}.chat{max-height:52vh}.msg{max-width:96%}body:before,body:after{opacity:.4}.card.stat{padding:.9rem 1rem}.stat b{font-size:1.6rem}.grid-3:has(>.stat){grid-template-columns:repeat(3,1fr);gap:.6rem}.hide-sm{display:none!important}.show-sm{display:inline}.table{font-size:.85rem}.table th,.table td{padding:.55rem .35rem}}@media print{.header,.lesson-top,footer,.btn{display:none!important}}