:root{--bg:#f4f7f2;--card:#fff;--ink:#1f2a22;--muted:#66736a;--line:#dde5dc;--accent:#2f7d55;--accent-ink:#fff;--good:#2f9e44;--good-bg:#e6f6e9;--bad:#d6336c;--bad-bg:#fde8ef;--right:#2f9e44;--right-border:#2b8a3e;--right-ink:#fff;--right-badge:#b2f2bb;--right-badge-ink:#1b5e20;--wrong-bg:#ffe3e3;--wrong-border:#e03131;--wrong-ink:#a51d1d;--wrong-badge:#ffc9c9;--soft:#eef1ed;--hover:#eef7f1;--ask-bg:linear-gradient(135deg, #edf6f0, #e9eff9);--flag-edge:#0003;--flag-shadow:#0000001f;--radius:16px;--shadow:0 1px 2px #1428190f, 0 8px 24px -12px #1428192e;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light}@media (prefers-color-scheme:dark){:root{--bg:#18201b;--card:#222c25;--ink:#eef3ee;--muted:#9faea3;--line:#34413a;--accent:#4fb07d;--accent-ink:#0f1712;--good:#69db7c;--good-bg:#1f3a27;--bad:#f783ac;--bad-bg:#3d2230;--right:#2f9e44;--right-border:#40c057;--right-ink:#fff;--right-badge:#b2f2bb;--right-badge-ink:#1b5e20;--wrong-bg:#42222a;--wrong-border:#ff6b6b;--wrong-ink:#ffc9c9;--wrong-badge:#6b2b35;--soft:#2a352e;--hover:#26392d;--ask-bg:linear-gradient(135deg, #1f2d24, #1f2733);--flag-edge:#ffffff29;--flag-shadow:#00000059;--shadow:0 1px 2px #0000004d, 0 8px 24px -12px #0009;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark}}*{box-sizing:border-box}body{background:var(--bg);color:var(--ink);margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;font-size:17px;line-height:1.45}button{font:inherit;color:inherit}h1,h2{margin:0 0 .4em;line-height:1.2}h1{font-size:1.4rem}h2{font-size:1.15rem}a{color:var(--accent)}.shell{flex-direction:column;max-width:640px;min-height:100vh;margin:0 auto;padding:0 16px;display:flex}.top{justify-content:space-between;align-items:center;gap:12px;padding:14px 0;display:flex}.logo{color:var(--ink);align-items:center;gap:8px;font-size:1.15rem;font-weight:700;text-decoration:none;display:flex}.top-right{align-items:center;gap:14px;display:flex}.link{color:var(--muted);cursor:pointer;background:0 0;border:0;padding:0;font-size:.95rem;text-decoration:none}.link:hover{color:var(--ink)}.user-slot{min-width:28px;min-height:28px;display:inline-flex}.page{flex-direction:column;flex:1;gap:16px;padding-bottom:24px;display:flex}.panel{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);padding:20px}.intro p,.muted{color:var(--muted)}.prose p{margin:0 0 .9em}.prose h2{margin-top:1.2em}.error{background:var(--bad-bg);color:var(--ink);border-radius:12px;margin:0;padding:12px 14px}.btn{background:var(--accent);min-height:44px;color:var(--accent-ink);cursor:pointer;border:0;border-radius:12px;justify-content:center;align-items:center;gap:6px;padding:8px 18px;font-weight:600;text-decoration:none;display:inline-flex}.btn.ghost{color:var(--accent);box-shadow:inset 0 0 0 2px var(--line);background:0 0}.btn.big{min-height:52px;font-size:1.05rem}.decks{gap:16px;margin:0;padding:0;list-style:none;display:grid}.deck{flex-direction:column;gap:4px;display:flex}.deck p{margin:0}.deck .btn{margin-top:12px}.preview{gap:8px;margin-bottom:12px;display:flex}.preview img{width:auto;height:44px}.preview img,.card-image{filter:drop-shadow(1px 0 0 var(--flag-edge)) drop-shadow(-1px 0 0 var(--flag-edge)) drop-shadow(0 1px 0 var(--flag-edge)) drop-shadow(0 -1px 0 var(--flag-edge)) drop-shadow(0 3px 6px var(--flag-shadow))}.counts{color:var(--muted);font-size:.95rem}.study-bar{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:6px 16px;display:flex}.stats{color:var(--muted);flex-wrap:wrap;gap:4px 14px;font-size:.9rem;display:flex}.card{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);flex-direction:column;gap:20px;padding:20px;transition:opacity .2s;display:flex}.card.leaving{opacity:.45}.card-ask,.card-answer{flex-direction:column;gap:12px;display:flex}.card-title{margin:0;font-size:1.2rem}.question{margin:0;font-size:1.1rem}.image-box{background:var(--soft);height:200px;box-shadow:var(--shadow);border-radius:12px;justify-content:center;align-items:center;padding:12px;display:flex;overflow:hidden}.card-image{object-fit:contain;opacity:0;width:100%;height:100%;transition:opacity .3s}.card-image.loaded{opacity:1}.card-image.error{opacity:.5}.select{margin:0;font-size:1.05rem;font-weight:600}.options{flex-direction:column;gap:12px;display:flex}.option{text-align:left;background:var(--card);border:2px solid var(--line);cursor:pointer;border-radius:12px;align-items:center;gap:12px;min-height:56px;padding:12px 14px;font-weight:500;transition:background .2s,border-color .2s,color .2s,transform .2s;display:flex}.option:not(:disabled):hover{background:var(--hover);border-color:var(--accent)}.option:disabled{cursor:not-allowed;color:var(--ink)}.option .key{background:var(--soft);width:32px;height:32px;color:var(--ink);border-radius:50%;flex:none;place-items:center;font-size:.9rem;font-weight:600;display:inline-grid}.option .label{flex:1}.option.right{background:var(--right);border-color:var(--right-border);color:var(--right-ink);animation:2s cubic-bezier(.4,0,.6,1) infinite pulse}.option.right:not(:disabled){cursor:pointer}.option.right:not(:disabled):hover{background:var(--right);border-color:var(--right-border)}.option.right .key{background:var(--right-badge);color:var(--right-badge-ink)}.option.wrong{background:var(--wrong-bg);border-color:var(--wrong-border);color:var(--wrong-ink)}.option.wrong .key{background:var(--wrong-badge);color:var(--wrong-ink)}.option.dim{background:var(--soft);color:var(--muted)}.option .continue{color:var(--right-ink);background:#00000047;border-radius:8px;flex:none;padding:4px 12px;font-size:.8rem;font-weight:700}@keyframes pulse{50%{opacity:.85}}@media (prefers-reduced-motion:reduce){.option.right{animation:none}}.sr-only{clip:rect(0 0 0 0);white-space:nowrap;border:0;width:1px;height:1px;margin:-1px;padding:0;position:absolute;overflow:hidden}.done{text-align:center;padding:32px 20px}.done-mark{margin-bottom:12px;font-size:3rem;line-height:1}.done p{margin:0 0 8px}.actions{flex-wrap:wrap;justify-content:center;gap:10px;margin-top:16px;display:flex}@media (width>=1024px){.shell.wide{max-width:1200px}.card{grid-template-columns:3fr 2fr;gap:0;min-height:600px;padding:0;display:grid;overflow:hidden}.card-ask,.card-answer{justify-content:center;padding:32px}.card-ask{background:var(--ask-bg);gap:24px}.card-title:after,.select:after{content:"";background:var(--accent);border-radius:2px;width:64px;height:4px;margin-top:8px;display:block}.select:after{background:var(--right);width:48px}.card-title{font-size:1.5rem}.question{font-size:1.5rem;font-weight:500}.image-box{height:320px}.card-answer{gap:20px}.select{font-size:1.25rem}.option{min-height:64px;padding:14px 16px;font-size:1.05rem}.option .key{width:40px;height:40px;font-size:1.05rem}.option:not(:disabled):hover{transform:scale(1.02)}}.footer{text-align:center;padding:20px 0;font-size:.9rem}.footer a{color:var(--muted)}