:root{--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;--bg:#fff6eb;--card:#fff;--text:#1c1917;--muted:#78716c;--line:#eadfd3;--primary:#2563eb;--primary-dark:#1d4ed8;--success:#15803d;--success-bg:#dcfce7;--danger:#dc2626;--danger-bg:#fee2e2;--shadow:0 10px 30px #1c191714;--radius:22px;color:var(--text);background:var(--bg);font-synthesis:none;text-rendering:optimizelegibility;-webkit-font-smoothing:antialiased;font-family:Segoe UI,PingFang SC,Microsoft YaHei,sans-serif;font-weight:500;line-height:1.45}*{box-sizing:border-box}html,body,#root{min-height:100%;margin:0}body{background:radial-gradient(circle at top right, #ffe7c7 0, transparent 32%), radial-gradient(circle at left 20%, #dbeafe 0, transparent 28%), var(--bg);min-height:100dvh}button,a{font:inherit}a{color:var(--primary-dark)}.app-shell{flex-direction:column;max-width:520px;min-height:100dvh;margin:0 auto;display:flex}.topbar{justify-content:space-between;align-items:center;padding:16px 18px 8px;display:flex}.brand{color:var(--text);font-size:1.15rem;font-weight:800;text-decoration:none}.top-nav{gap:14px;display:flex}.top-nav a{color:var(--muted);font-weight:700;text-decoration:none}.app-main{flex:1;padding:8px 16px 28px}.page{flex-direction:column;gap:16px;display:flex}.page h1{margin:8px 0 0;font-size:1.8rem}.hero-copy{padding:12px 4px 4px}.hero-copy h1{margin:0;font-size:2.2rem}.hero-copy p,.muted,.hint,.fineprint{color:var(--muted)}.grade-grid{grid-template-columns:1fr 1fr;gap:12px;display:grid}.grade-card{border-radius:var(--radius);color:#fff;min-height:108px;box-shadow:var(--shadow);flex-direction:column;gap:6px;padding:18px;text-decoration:none;display:flex}.grade-name{font-size:1.25rem;font-weight:800}.grade-blurb{opacity:.92;font-size:.92rem}.grade-1{background:linear-gradient(135deg,#f97316,#ea580c)}.grade-2{background:linear-gradient(135deg,#eab308,#ca8a04)}.grade-3{background:linear-gradient(135deg,#22c55e,#15803d)}.grade-4{background:linear-gradient(135deg,#06b6d4,#0891b2)}.grade-5{background:linear-gradient(135deg,#3b82f6,#1d4ed8)}.grade-6{background:linear-gradient(135deg,#8b5cf6,#6d28d9)}.home-links,.action-row,.banner-actions,.chip-row{flex-wrap:wrap;gap:10px;display:flex}.panel{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:16px}.panel h2,.subhead{margin:0 0 10px;font-size:1rem}.subhead{margin-top:16px}.panel-head{justify-content:space-between;align-items:center;gap:8px;margin-bottom:8px;display:flex}.chip,.text-btn,.ghost-btn,.ghost-link,.primary-btn{cursor:pointer;border:0;border-radius:999px}.chip{color:var(--text);background:#f5efe8;padding:10px 14px}.chip-on{background:var(--primary);color:#fff}.chip-adv:not(.chip-on){box-shadow:inset 0 0 0 1px #fdba74}.primary-btn,.ghost-link.center,.primary-btn.center{background:var(--primary);color:#fff;justify-content:center;align-items:center;min-height:52px;padding:0 22px;font-weight:800;text-decoration:none;display:inline-flex}.primary-btn:hover{background:var(--primary-dark)}.primary-btn.compact{min-height:44px}.ghost-btn,.ghost-link{min-height:44px;color:var(--text);background:#f5efe8;justify-content:center;align-items:center;padding:0 16px;font-weight:700;text-decoration:none;display:inline-flex}.text-btn{color:var(--muted);background:0 0;padding:8px}.practice{flex-direction:column;gap:12px;padding-top:8px;display:flex}.practice-bar{grid-template-columns:64px 1fr 64px;align-items:center;display:grid}.progress,.timer{text-align:center;margin:0;font-weight:800}.timer{text-align:right}.progress-line{background:#f0e7dc;border-radius:99px;height:8px;overflow:hidden}.progress-line span{background:var(--primary);height:100%;display:block}.prompt{flex-wrap:wrap;justify-content:center;align-items:center;gap:8px 10px;min-height:108px;padding:12px 4px;font-size:2.4rem;font-weight:800;display:flex}.token-op{color:var(--primary-dark)}.token-text{font-size:1.4rem}.token-blank{color:var(--muted)}.frac{vertical-align:middle;flex-direction:column;align-items:center;line-height:1;display:inline-flex}.frac-n,.frac-d{padding:0 6px}.frac-n{border-bottom:4px solid;margin-bottom:4px}.input-single,.input-value{justify-content:center;align-items:center;min-height:64px;font-size:2.2rem;font-weight:800;display:flex}.input-single{background:var(--card);border:2px solid var(--line);border-radius:18px}.dual-input{grid-template-columns:1fr 1fr;gap:10px;display:grid}.input-box{border:2px solid var(--line);background:var(--card);border-radius:18px;padding:8px}.input-on{border-color:var(--primary)}.input-label{color:var(--muted);font-size:.85rem;display:block}.hint,.fineprint{text-align:center;margin:0;font-size:.92rem}.banner{text-align:center;border-radius:18px;padding:14px;font-weight:800}.banner-ok{background:var(--success-bg);color:var(--success)}.banner-bad{background:var(--danger-bg);color:var(--danger)}.banner-answer{justify-content:center;align-items:center;gap:8px;font-size:1.2rem;display:flex}.pad{grid-template-columns:repeat(3,1fr);gap:10px;margin-top:6px;display:grid}.pad-key,.pad-submit{background:var(--card);min-height:58px;box-shadow:var(--shadow);cursor:pointer;border:0;border-radius:16px;font-size:1.4rem;font-weight:800}.pad-key:disabled,.pad-submit:disabled{opacity:.45;cursor:not-allowed}.pad-muted{color:var(--muted)}.pad-submit{background:var(--primary);color:#fff;grid-column:1/-1}.score-card{text-align:center;border-radius:var(--radius);background:var(--card);box-shadow:var(--shadow);padding:24px 12px}.score-label,.score-meta{color:var(--muted);margin:0}.score-value{margin:4px 0;font-size:4rem;line-height:1}.score-great{background:var(--success-bg)}.score-ok{background:#fef3c7}.score-low{background:var(--danger-bg)}.review-list,.history-list{flex-direction:column;gap:12px;margin:0;padding:0;list-style:none;display:flex}.review-item,.history-item{background:#fffaf4;border-radius:16px;padding:12px}.review-item .prompt{justify-content:flex-start;min-height:0;padding:0 0 8px;font-size:1.5rem}.history-item{justify-content:space-between;gap:12px;display:flex}.history-title{margin:0;font-weight:800}.history-score{color:var(--muted);flex-direction:column;align-items:flex-end;font-size:.9rem;display:flex}.history-score strong{color:var(--text);font-size:1.3rem}.celebrate{text-align:center;color:var(--success);font-size:1.3rem;font-weight:800}.feature-card{border-radius:var(--radius);min-height:108px;box-shadow:var(--shadow);color:#fff;background:linear-gradient(135deg,#334155,#0f172a);flex-direction:column;gap:6px;padding:18px;text-decoration:none;display:flex}.feature-title{font-size:1.25rem;font-weight:800}.feature-blurb{opacity:.88;font-size:.92rem}.measure{max-width:62ch}.paper-workspace,.paper-controls{gap:12px;display:grid}.paper-page{gap:12px}.paper-page h1{margin:0;font-size:1.5rem}.paper-page .panel{padding:13px 14px}.paper-page .panel h2,.paper-page .subhead{margin-bottom:8px}.paper-page .subhead{margin-top:12px}.paper-page .chip{padding:8px 12px;font-size:.95rem}.paper-page .chip-row{gap:8px}.option-grid{grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:10px 14px;display:grid}.option-label{color:var(--muted);margin-bottom:6px;font-size:.85rem;font-weight:700;display:block}.preview-head{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:10px;margin-bottom:10px;display:flex}.preview-frame{aspect-ratio:210/297;border:1px solid var(--line);background:#f3efe9;border-radius:12px;position:relative;overflow:hidden}.preview-frame iframe{border:0;width:100%;height:100%;display:block}.preview-empty{place-items:center;height:100%;margin:0;display:grid}.preview-badge{color:#fff;background:#1c1917b8;border-radius:999px;padding:4px 10px;font-size:.78rem;font-weight:700;position:absolute;top:10px;right:10px}.paper-actions{flex-wrap:wrap;align-items:center;gap:10px;margin-top:12px;display:flex}.paper-actions .ghost-link{min-height:44px}.paper-actions .primary-btn:disabled{opacity:.5;cursor:not-allowed}.setup-error{color:var(--danger);margin:0;font-weight:700}@media (width>=640px){.prompt{font-size:3rem}.option-grid{grid-template-columns:1fr 1fr;gap:18px}}