:root{color-scheme:light dark;--bg:light-dark(#f3f6f7,#101921);--surface:light-dark(#fff,#182630);--surface-2:light-dark(#eaf3f3,#233c42);--ink:light-dark(#192f3a,#eef4f6);--ink-2:light-dark(#536873,#adc0ca);--line:light-dark(#d5e0e5,#354a56);--line-2:var(--line);--accent:light-dark(#086971,#81cdd1);--accent-ink:light-dark(#fff,#102329)}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.6 -apple-system,BlinkMacSystemFont,"Apple SD Gothic Neo",sans-serif}header{background:var(--surface);border-top:4px solid var(--accent);border-bottom:1px solid var(--line);padding:18px max(18px,calc((100% - 980px)/2));display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap}header strong{font-size:18px}small{display:block;font-size:13px;color:var(--ink-2)}main{max-width:980px;margin:auto;padding:28px 20px 40px}h1{font-size:29px;margin:0 0 7px;letter-spacing:-.04em}h2{font-size:21px;margin:0 0 14px}p{color:var(--ink-2);margin:0 0 16px}a{color:var(--accent)}button,input{font:inherit}button,.action{border:1px solid var(--line);border-radius:5px;background:var(--surface);color:var(--ink);padding:9px 14px;min-height:44px;cursor:pointer;text-decoration:none;display:inline-block}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid var(--accent);outline-offset:3px}.primary{background:var(--accent);color:var(--accent-ink);border-color:var(--accent)}.actions{display:flex;gap:10px;flex-wrap:wrap}.summary{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border:1px solid var(--line);margin:22px 0}.summary div{padding:17px;background:var(--surface)}.summary b{display:block;font-size:25px;font-variant-numeric:tabular-nums}.panel{padding:24px;border:1px solid var(--line);background:var(--surface);border-radius:8px;margin-bottom:22px}.next{border-top:3px solid var(--accent)}.next h2{font-size:25px;line-height:1.4;margin:10px 0 16px}.next .action{font-size:18px;min-height:50px;padding:11px 20px}.choices{display:flex;gap:12px;flex-wrap:wrap;margin:12px 0 20px}.choices label{display:flex;gap:8px;align-items:center;padding:10px 14px;background:var(--surface-2);border:1px solid var(--line);border-radius:6px;cursor:pointer}.choices input{width:18px;height:18px}.lesson{display:flex;align-items:center;gap:14px;padding:15px 0;border-bottom:1px solid var(--line)}.lesson:last-child{border-bottom:0}.lesson-text{flex:1}.lesson .order{font-size:19px;min-width:24px;color:var(--accent)}.lesson small{margin-top:4px}.label{color:var(--accent);font-size:13px}.empty{padding:12px 0;color:var(--ink-2)}.notice{font-size:13px;color:var(--ink-2);margin-top:24px}.error{padding:24px;border:1px solid var(--line);background:var(--surface)}footer{display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;font-size:14px;margin-top:24px}.muted{color:var(--ink-2)}[hidden]{display:none!important}@media(max-width:540px){main{padding:24px 16px}.panel{padding:20px}.summary div{padding:13px 10px}.summary b{font-size:21px}.summary small{font-size:12px}.lesson{flex-wrap:wrap;gap:10px}.lesson .action{margin-left:34px}.next .action{display:block;text-align:center}h1{font-size:26px}}