/* 书页 · 分支阅读 */
:root{
  --bg:#faf8f4; --paper:#fffdfa; --line:#e8e1d6; --line2:#f2ece2;
  --tx:#241f1a; --tx2:#4d453c; --dim:#776c5e; --faint:#a2978a;
  --ac:#8c5a2b; --ac-soft:#f5ece0; --ink:#1d1a17;
  --serif:"Songti SC","Source Han Serif SC","Noto Serif CJK SC",Georgia,"Songti SC",serif;
  --sans:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;background:var(--bg)}
body{
  margin:0;background:var(--bg);color:var(--tx);
  font:15px/1.7 var(--sans);
  -webkit-font-smoothing:antialiased;
}
button{font-family:inherit}

/* ---------- 顶栏 ---------- */
.top{position:sticky;top:0;z-index:30;background:rgba(250,248,244,.9);backdrop-filter:blur(12px) saturate(160%);border-bottom:1px solid var(--line)}
.bar{max-width:760px;margin:0 auto;padding:0 20px;height:56px;display:flex;align-items:center;justify-content:space-between}
.brand{display:flex;align-items:center;gap:9px;color:var(--tx);text-decoration:none;font-weight:650;font-size:15px;letter-spacing:.2px}
.brand .mark{
  width:26px;height:26px;border-radius:7px;background:var(--ink);color:#faf8f4;
  display:grid;place-items:center;font:600 14px/1 var(--serif);flex:0 0 auto;
}
.brand em{font-style:normal;color:var(--faint);font-weight:400;font-size:10.5px;letter-spacing:.6px;margin-left:6px}
.tools{display:flex;gap:4px}
.ghost{
  border:1px solid transparent;background:transparent;color:var(--dim);
  padding:6px 10px;border-radius:8px;font-size:12.5px;cursor:pointer;transition:.15s;
}
.ghost:hover{background:#f1ebe1;color:var(--tx)}
.ghost.sm{font-size:12px;padding:5px 9px}

/* 进度条 */
.progress{height:2px;background:var(--line2);overflow:hidden}
.progress i{display:block;height:100%;width:0;background:linear-gradient(90deg,#c08a4e,#8c5a2b);transition:width .45s cubic-bezier(.4,0,.2,1)}

/* ---------- 通用 ---------- */
.view{max-width:760px;margin:0 auto;padding:0 20px 80px}
.hero{padding:46px 0 30px}
.hero h1{font:600 27px/1.45 var(--serif);margin:0 0 12px;letter-spacing:-.2px}
.hero p{margin:0;color:var(--dim);font-size:14px;line-height:1.8;max-width:560px}

/* ---------- 导入 ---------- */
.import{
  border:1.5px dashed #d9cfc0;border-radius:14px;background:rgba(255,253,250,.6);
  cursor:pointer;transition:.18s;overflow:hidden;
}
.import:hover,.import.over{border-color:#b98d55;background:#fffdf8;box-shadow:0 4px 18px rgba(140,90,43,.07)}
.import-in{display:flex;flex-direction:column;align-items:center;gap:4px;padding:30px 20px;text-align:center}
.import-ico{
  width:38px;height:38px;border-radius:50%;background:var(--ac-soft);color:var(--ac);
  display:grid;place-items:center;font-size:20px;margin-bottom:4px;
}
.import b{font-size:14px;font-weight:650}
.import span{font-size:12px;color:var(--faint)}

.or{display:flex;align-items:center;gap:12px;margin:16px 0;color:var(--faint);font-size:11.5px}
.or::before,.or::after{content:"";flex:1;height:1px;background:var(--line2)}
.demo{
  width:100%;border:1px solid var(--line);background:var(--paper);color:var(--tx2);
  border-radius:11px;padding:11px;font-size:13px;cursor:pointer;transition:.15s;
}
.demo:hover{background:#fff;border-color:#d9cfc0;color:var(--tx)}

.sec{font:600 13px/1 var(--sans);color:var(--faint);letter-spacing:1.2px;text-transform:uppercase;margin:34px 0 12px}
.shelf{display:grid;gap:10px}
.empty{color:var(--faint);font-size:13px;padding:22px 0;text-align:center}

.book{
  display:flex;align-items:center;gap:13px;padding:13px 15px;background:var(--paper);
  border:1px solid var(--line);border-radius:12px;cursor:pointer;transition:.16s;position:relative;
}
.book:hover{border-color:#d5c8b6;box-shadow:0 3px 14px rgba(120,100,80,.07);transform:translateY(-1px)}
.book .spine{
  width:34px;height:44px;border-radius:4px;flex:0 0 auto;
  background:linear-gradient(135deg,#a9764a,#7d4f27);
  box-shadow:inset 0 0 0 1px rgba(255,255,255,.18),inset 2px 0 0 rgba(255,255,255,.16);
}
.book .bi{flex:1;min-width:0}
.book .bi b{display:block;font-size:14px;font-weight:650;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;margin-bottom:3px}
.book .bi span{font-size:11.5px;color:var(--faint)}
.book .del{
  border:0;background:transparent;color:#c9bfb1;font-size:16px;cursor:pointer;padding:2px 4px;line-height:1;
  opacity:0;transition:.15s;
}
.book:hover .del{opacity:1}
.book .del:hover{color:#b91c1c}

/* ---------- 阅读 ---------- */
.read-head{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:20px 0 10px}
.back{border:0;background:transparent;color:var(--faint);font-size:12.5px;cursor:pointer;padding:4px 0}
.back:hover{color:var(--ac)}
.meta{display:flex;align-items:center;gap:8px;font-size:11.5px;color:var(--faint);min-width:0}
.meta i{width:3px;height:3px;border-radius:50%;background:#cfc4b4;flex:0 0 auto}
.meta span{white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:200px}

.paper{
  background:var(--paper);border:1px solid var(--line);border-radius:16px;
  padding:34px 38px 30px;margin-top:10px;
  box-shadow:0 2px 24px rgba(120,100,80,.05);
}
.paper h2{
  font:600 19px/1.5 var(--serif);margin:0 0 6px;letter-spacing:-.1px;
}
.paper .kicker{font-size:11px;color:var(--faint);letter-spacing:1.4px;text-transform:uppercase;margin-bottom:14px}
.paper p{font:16.5px/1.95 var(--serif);color:var(--tx);margin:0 0 1.05em;text-align:justify;text-justify:inter-ideograph}
.paper p:last-child{margin-bottom:0}
.paper .sep{text-align:center;color:#d5c8b6;letter-spacing:.5em;margin:1.4em 0;font-size:12px}
.paper .src{font-size:11.5px;color:var(--faint);margin:0 0 6px;font-family:var(--sans)}
.paper .note{
  margin:22px 0 0;padding:11px 13px;background:var(--ac-soft);border-radius:9px;
  font-size:12px;color:#6f4a20;line-height:1.65;font-family:var(--sans);
}
.paper .ai-tag{
  display:inline-flex;align-items:center;gap:5px;font-size:10.5px;color:#8a6a42;
  background:#f6ebdc;border-radius:99px;padding:3px 9px;margin-bottom:12px;font-family:var(--sans);
}
.paper.loading p{opacity:.35}
.paper.loading::after{
  content:"";position:absolute;
}

/* 选择 */
.choices{display:grid;gap:9px;margin-top:18px}
.choice{
  display:flex;align-items:center;gap:12px;width:100%;text-align:left;
  background:var(--paper);border:1px solid var(--line);border-radius:12px;
  padding:13px 16px;cursor:pointer;transition:.16s;color:var(--tx);
}
.choice:hover{border-color:#c9a97d;background:#fffdf8;transform:translateX(2px);box-shadow:0 3px 14px rgba(140,90,43,.07)}
.choice .k{
  width:24px;height:24px;border-radius:7px;flex:0 0 auto;display:grid;place-items:center;
  font-size:11px;font-weight:600;background:#f2ece1;color:#9a805f;
}
.choice.main .k{background:var(--ink);color:#faf8f4}
.choice.return .k{background:#eaf1ea;color:#4a7a52}
.choice .ct{flex:1;min-width:0}
.choice .ct b{display:block;font-size:13.5px;font-weight:600;margin-bottom:2px}
.choice .ct span{font-size:11.5px;color:var(--faint);display:block;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.choice .ar{color:#c9bfb1;font-size:14px}

.read-foot{display:flex;align-items:center;justify-content:space-between;margin-top:20px;color:var(--faint);font-size:11.5px}

/* ---------- 抽屉 ---------- */
.drawer[hidden]{display:none}
.drawer{position:fixed;inset:0;z-index:60;background:rgba(36,31,26,.32);display:flex;justify-content:flex-end;backdrop-filter:blur(2px)}
.drawer-card{
  width:min(400px,92vw);height:100%;background:var(--bg);padding:20px 22px 28px;
  overflow-y:auto;box-shadow:-8px 0 40px rgba(60,45,30,.14);animation:slide .22s ease-out;
}
@keyframes slide{from{transform:translateX(18px);opacity:.6}to{transform:none;opacity:1}}
.dc-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px}
.dc-head b{font-size:14px}
.x{border:0;background:transparent;font-size:20px;color:var(--faint);cursor:pointer;line-height:1}
.x:hover{color:var(--tx)}

.sw{display:flex;gap:11px;align-items:flex-start;padding:13px;background:var(--paper);border:1px solid var(--line);border-radius:11px;cursor:pointer;margin-bottom:14px}
.sw input{margin-top:2px;accent-color:var(--ac);width:15px;height:15px;flex:0 0 auto}
.sw b{display:block;font-size:13px;font-weight:600}
.sw i{font-style:normal;display:block;font-size:11.5px;color:var(--faint);margin-top:2px;line-height:1.5}

.ai-fields{display:grid;gap:12px}
.ai-fields label{display:block;font-size:12px;font-weight:600;color:var(--tx2)}
.ai-fields label small{display:block;font-weight:400;color:var(--faint);font-size:11px;margin:1px 0 6px}
.ai-fields input{
  width:100%;border:1px solid var(--line);border-radius:9px;background:var(--paper);
  padding:9px 11px;font-size:12.5px;color:var(--tx);outline:none;font-family:var(--sans);
}
.ai-fields input:focus{border-color:#c9a97d;box-shadow:0 0 0 3px var(--ac-soft)}
.presets{display:flex;flex-wrap:wrap;gap:6px;margin-top:2px}
.presets button{
  border:1px solid var(--line);background:var(--paper);border-radius:99px;
  padding:4px 10px;font-size:11px;color:var(--dim);cursor:pointer;transition:.15s;
}
.presets button:hover{background:var(--ac-soft);border-color:#d8c3a4;color:#7a5127}
.dc-note{margin:18px 0 0;font-size:11px;color:var(--faint);line-height:1.7}

/* ---------- toast ---------- */
.toast{
  position:fixed;left:50%;bottom:28px;transform:translateX(-50%);z-index:90;
  background:var(--ink);color:#faf8f4;font-size:12.5px;padding:9px 16px;border-radius:99px;
  box-shadow:0 6px 24px rgba(30,24,18,.24);max-width:80vw;text-align:center;
}
.toast.err{background:#8c2f2a}

/* ---------- 手机 ---------- */
@media (max-width:640px){
  .view{padding:0 16px 70px}
  .hero{padding:32px 0 22px}
  .hero h1{font-size:22px}
  .hero p{font-size:13px}
  .paper{padding:24px 20px 22px;border-radius:13px}
  .paper p{font:16px/1.9 var(--serif)}
  .meta span{max-width:120px}
  .choice{padding:12px 13px}
  .drawer-card{padding:18px 16px 24px}
}