:root {
  --bg: #f5efe3;
  --fg: #2b2b2b;
  --muted: #7a6f5f;
  --accent: #8b5a2b;
  --card: #fbf6ea;
  --border: #d8cdb5;
  --shadow: 0 1px 3px rgba(60, 40, 10, .08);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1a1815;
    --fg: #d8d2c4;
    --muted: #8a8170;
    --accent: #d4a373;
    --card: #22201c;
    --border: #3a362e;
    --shadow: 0 1px 3px rgba(0, 0, 0, .3);
  }
}
html[data-theme="light"] {
  --bg: #f5efe3; --fg: #2b2b2b; --muted: #7a6f5f; --accent: #8b5a2b;
  --card: #fbf6ea; --border: #d8cdb5; --shadow: 0 1px 3px rgba(60, 40, 10, .08);
}
html[data-theme="dark"] {
  --bg: #1a1815; --fg: #d8d2c4; --muted: #8a8170; --accent: #d4a373;
  --card: #22201c; --border: #3a362e; --shadow: 0 1px 3px rgba(0, 0, 0, .3);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; background: var(--bg); color: var(--fg); }
body {
  font-family: "Noto Serif TC", "Source Han Serif TC", "Songti TC", "PingFang TC", Georgia, serif;
  line-height: 1.85;
  -webkit-text-size-adjust: 100%;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: 720px; margin: 0 auto; padding: 24px 18px 80px; }

/* 頂部列 */
.topbar {
  position: sticky; top: 0; z-index: 10;
  background: var(--bg); border-bottom: 1px solid var(--border);
  padding: 10px 16px; display: flex; gap: 12px; align-items: center;
}
.topbar a, .topbar button {
  color: var(--fg); background: transparent; border: 0; cursor: pointer;
  font-size: 15px; padding: 6px 10px; border-radius: 6px;
}
.topbar button:hover, .topbar a:hover { background: var(--card); text-decoration: none; }
.topbar button.active { background: var(--accent); color: #fff; }
.topbar .title { flex: 1; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* 分段按鈕（自動捲動速度） */
.topbar .seg { display: inline-flex; border: 1px solid var(--border); border-radius: 6px; overflow: hidden; }
.topbar .seg button {
  padding: 6px 10px; border-radius: 0; font-size: 13px;
  border-right: 1px solid var(--border);
}
.topbar .seg button:last-child { border-right: 0; }
.topbar .seg button:hover { background: var(--card); }

.topbar .speed-label {
  display: inline-block; min-width: 32px; text-align: center;
  color: var(--muted); font-size: 13px; font-variant-numeric: tabular-nums;
}

/* 手機上 topbar 水平捲動避免擠爆 */
.topbar { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.topbar::-webkit-scrollbar { height: 0; }
.topbar > * { flex-shrink: 0; }
.topbar .title { flex-shrink: 1; min-width: 0; }

/* 書架 */
.shelf { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 18px; }
.book-card {
  background: var(--card); border: 1px solid var(--border); border-radius: 8px;
  padding: 12px; box-shadow: var(--shadow); cursor: pointer;
  display: flex; flex-direction: column; gap: 8px;
}
.book-card img {
  width: 100%; aspect-ratio: 3/4; object-fit: cover; border-radius: 4px; background: var(--border);
}
.book-card .b-title { font-weight: 600; font-size: 15px; line-height: 1.4; }
.book-card .b-meta { color: var(--muted); font-size: 12px; }
.category-group { margin-bottom: 28px; }
.category-group h2 {
  font-size: 16px; color: var(--muted); margin: 0 0 12px; font-weight: 500;
  border-left: 3px solid var(--accent); padding-left: 8px;
}

/* 書目錄 */
.book-header {
  display: flex; gap: 18px; padding: 18px 0 24px; border-bottom: 1px solid var(--border); margin-bottom: 20px;
}
.book-header img { width: 120px; aspect-ratio: 3/4; object-fit: cover; border-radius: 6px; background: var(--border); }
.book-header .info { flex: 1; }
.book-header h1 { margin: 0 0 8px; font-size: 22px; }
.book-header .meta { color: var(--muted); font-size: 14px; line-height: 1.7; }
.book-header .resume {
  margin-top: 12px; display: inline-block; background: var(--accent); color: #fff;
  padding: 8px 16px; border-radius: 6px; font-size: 14px;
}
.book-header .resume:hover { text-decoration: none; opacity: .9; }

.toc-controls {
  display: flex; gap: 8px; align-items: center; margin-bottom: 12px;
}
.toc-controls input {
  flex: 1; padding: 8px 12px; border: 1px solid var(--border); border-radius: 6px;
  background: var(--card); color: var(--fg); font-size: 14px;
}
.toc { list-style: none; padding: 0; margin: 0; }
.toc li { border-bottom: 1px solid var(--border); }
.toc a { display: block; padding: 10px 4px; color: var(--fg); }
.toc a:hover { background: var(--card); text-decoration: none; }
.toc a.read { color: var(--muted); }
.toc .ch-num { display: inline-block; min-width: 48px; color: var(--muted); font-size: 13px; }

/* 純文字章節清單（不可點） */
.toc-plain {
  list-style: decimal inside;
  padding: 0; margin: 0;
  color: var(--fg);
  counter-reset: chapter;
}
.toc-plain li {
  padding: 8px 6px; border-bottom: 1px solid var(--border);
  font-size: 15px; line-height: 1.5;
  user-select: text;
}
.toc-plain li.current {
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  border-left: 3px solid var(--accent);
  padding-left: 10px;
  font-weight: 600;
}
.toc-plain li.loading { color: var(--muted); border: 0; padding: 20px 0; text-align: center; }
.toc-plain li::marker { color: var(--muted); font-size: 13px; }

/* 閱讀頁 */
.reader {
  font-size: var(--reader-size, 18px);
  padding: 24px 6px 120px;
}
.reader h1 { font-size: 1.4em; border-bottom: 1px solid var(--border); padding-bottom: 10px; margin-bottom: 20px; }
.reader p { margin: 1em 0; text-indent: 2em; }

.pager {
  position: fixed; left: 0; right: 0; bottom: 0;
  background: var(--bg); border-top: 1px solid var(--border);
  display: flex; gap: 8px; padding: 10px 12px; max-width: 720px; margin: 0 auto;
}
.pager button, .pager a {
  flex: 1; text-align: center; padding: 10px; border-radius: 6px;
  background: var(--card); color: var(--fg); border: 1px solid var(--border);
  font-size: 14px; cursor: pointer;
}
.pager button:disabled, .pager a.disabled { opacity: .4; pointer-events: none; }
.pager a:hover { text-decoration: none; background: var(--border); }

.loading { text-align: center; color: var(--muted); padding: 40px 0; }