:root{--bg:#f7f5ef;--panel:#fffdf8;--ink:#222;--muted:#6b645c;--line:#ded6c9;--accent:#5d725a;--bad:#9b3838;--good:#2f7044;--warn:#a06d20;}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--ink);font-family:ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1.45}
.topbar{position:sticky;top:0;z-index:10;background:rgba(247,245,239,.96);border-bottom:1px solid var(--line);display:flex;gap:24px;justify-content:space-between;align-items:end;padding:18px 24px}
.topbar h1{margin:0;font-size:24px}.sub{margin:4px 0 0;color:var(--muted);max-width:820px}.stats{display:flex;gap:10px;color:var(--muted);font-size:14px;white-space:nowrap}
.layout{display:grid;grid-template-columns:310px 1fr;gap:20px;max-width:1440px;margin:0 auto;padding:20px}
.sidebar{position:sticky;top:96px;align-self:start;background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:16px;box-shadow:0 1px 8px rgba(0,0,0,.04)}
label{display:block;font-weight:650;margin-bottom:12px}input,select{width:100%;margin-top:5px;padding:9px 10px;border:1px solid var(--line);border-radius:8px;background:#fff;color:var(--ink)}
button{border:1px solid var(--line);background:#fff;border-radius:9px;padding:9px 12px;cursor:pointer;font-weight:650}button:hover{border-color:var(--accent)}
.buttonrow{display:flex;gap:8px;margin:9px 0}.buttonrow button{flex:1}.hint{font-size:13px;color:var(--muted)}
details{margin-top:14px}summary{cursor:pointer;font-weight:700}#toc{margin-top:8px;max-height:42vh;overflow:auto;font-size:13px}
.tocItem{display:flex;justify-content:space-between;gap:8px;border-bottom:1px dashed var(--line);padding:5px 0;color:var(--muted)}
.cards{display:flex;flex-direction:column;gap:16px}.card{background:var(--panel);border:1px solid var(--line);border-radius:16px;padding:18px;box-shadow:0 1px 8px rgba(0,0,0,.04)}
.cardHead{display:flex;justify-content:space-between;align-items:flex-start;gap:12px}.badge{display:inline-block;background:#ebe5da;color:#584d41;border-radius:999px;padding:3px 9px;font-size:12px;font-weight:800}
.card h2{font-size:18px;margin:7px 0 2px}.meta{margin:0;color:var(--muted);font-size:13px}.mark{font-size:22px;line-height:1;padding:6px 10px}.mark.on{color:var(--warn);border-color:var(--warn)}
.stem{font-size:17px;margin:16px 0}.figures{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px;margin:12px 0}
.figure{border:1px solid var(--line);background:#fff;border-radius:12px;padding:10px}.figure img{max-width:100%;display:block;margin:0 auto;border-radius:8px}.figure figcaption{font-size:12px;color:var(--muted);margin-top:6px}
.options{display:grid;gap:8px}.option{display:grid;grid-template-columns:34px 1fr;align-items:start;gap:8px;border:1px solid var(--line);background:#fff;border-radius:10px;padding:10px;text-align:left;font-weight:500}
.option .letter{font-weight:900}.option.correct{border-color:var(--good);background:#eef8f0}.option.wrong{border-color:var(--bad);background:#fff0ef}
.actions{display:flex;align-items:center;gap:12px;margin-top:12px}.status{font-weight:700}.status.good{color:var(--good)}.status.bad{color:var(--bad)}
.answerBox{display:none;border-left:4px solid var(--accent);padding:10px 12px;margin-top:12px;background:#f2f0e8;border-radius:8px}.answerBox.show{display:block}.answer{display:block;margin-bottom:6px}.explanation{margin:0;color:#34312d}
.empty{padding:40px;text-align:center;color:var(--muted);background:var(--panel);border:1px dashed var(--line);border-radius:16px}
@media(max-width:900px){.layout{grid-template-columns:1fr}.sidebar{position:static}.topbar{position:static;display:block}.stats{margin-top:8px}.figures{grid-template-columns:1fr}}

.pw-overlay{position:fixed;inset:0;z-index:9999;background:rgba(0,0,0,.5);display:flex;align-items:center;justify-content:center;backdrop-filter:blur(4px)}
.pw-box{background:var(--panel);border:1px solid var(--line);border-radius:20px;padding:36px 40px;width:380px;max-width:90vw;text-align:center;box-shadow:0 12px 48px rgba(0,0,0,.2)}
.pw-box h1{margin:0 0 4px;font-size:22px}
.pw-sub{margin:4px 0 20px;color:var(--muted);font-size:15px}
.pw-box input{width:100%;padding:11px 14px;border:2px solid var(--line);border-radius:10px;font-size:16px;text-align:center}
.pw-box input:focus{border-color:var(--accent);outline:none}
.pw-box button{margin-top:14px;width:100%;padding:11px;border:none;border-radius:10px;background:var(--accent);color:#fff;font-size:16px;font-weight:700;cursor:pointer}
.pw-box button:hover{opacity:.9}
.pw-error{color:var(--bad);font-size:14px;margin:8px 0 0;min-height:20px}