:root {
  --bg: #e8e4dc;
  --bg-deep: #d9d3c7;
  --ink: #1c2420;
  --ink-soft: #4a554e;
  --accent: #2f6f5e;
  --accent-2: #c45c26;
  --card: rgba(255, 252, 245, 0.92);
  --line: rgba(28, 36, 32, 0.12);
  --shadow: 0 18px 50px rgba(20, 28, 24, 0.18);
  --font-display: "ZCOOL XiaoWei", "Noto Serif SC", serif;
  --font-body: "Noto Serif SC", "Source Han Serif SC", "Songti SC", serif;
  --fs: 18px;
  --lh: 1.85;
  --safe-b: env(safe-area-inset-bottom, 0px);
}

[data-theme="night"] {
  --bg: #12171a;
  --bg-deep: #0c1012;
  --ink: #e7ebe8;
  --ink-soft: #9aa69e;
  --accent: #6fb39a;
  --accent-2: #e09a6a;
  --card: rgba(24, 30, 34, 0.94);
  --line: rgba(231, 235, 232, 0.12);
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.45);
}

[data-theme="ash"] {
  --bg: #cfd4d6;
  --bg-deep: #b7bdbf;
  --ink: #22282b;
  --ink-soft: #5a6468;
  --accent: #3d5c66;
  --accent-2: #8a5a3c;
  --card: rgba(236, 239, 240, 0.94);
  --line: rgba(34, 40, 43, 0.14);
}

* { box-sizing: border-box; }
html, body {
  margin: 0;
  min-height: 100%;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  -webkit-font-smoothing: antialiased;
}
button { font: inherit; cursor: pointer; border: 0; background: none; color: inherit; }
.hidden { display: none !important; }

#app { min-height: 100vh; }

.view-cover {
  min-height: 100vh;
  display: grid;
  place-items: center;
  position: relative;
  overflow: hidden;
  padding: 24px;
}
.cover-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 50% 20%, rgba(47, 111, 94, 0.22), transparent 60%),
    linear-gradient(165deg, #2a3538 0%, #1a2228 45%, #0f1417 100%);
}
.cover-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(
    180deg,
    transparent 0,
    transparent 10px,
    rgba(255, 255, 255, 0.015) 11px
  );
  animation: rain 8s linear infinite;
  pointer-events: none;
}
@keyframes rain {
  from { transform: translateY(-20px); }
  to { transform: translateY(20px); }
}

.cover-card {
  position: relative;
  width: min(420px, 100%);
  padding: 40px 32px 36px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: linear-gradient(180deg, rgba(255, 252, 245, 0.08), rgba(255, 252, 245, 0.03));
  backdrop-filter: blur(8px);
  color: #f2f0ea;
  text-align: center;
  box-shadow: var(--shadow);
}
.cover-eyebrow {
  margin: 0 0 18px;
  letter-spacing: 0.28em;
  font-size: 12px;
  text-transform: uppercase;
  color: rgba(242, 240, 234, 0.65);
}
.cover-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(42px, 10vw, 56px);
  font-weight: 400;
  letter-spacing: 0.18em;
  text-indent: 0.18em;
}
.cover-sub {
  margin: 10px 0 0;
  font-size: 18px;
  letter-spacing: 0.2em;
  color: #d8c3a8;
}
.cover-desc {
  margin: 22px 0 0;
  font-size: 14px;
  letter-spacing: 0.12em;
  color: rgba(242, 240, 234, 0.7);
}
.cover-meta {
  margin: 28px 0 0;
  font-size: 13px;
  color: rgba(242, 240, 234, 0.55);
}
.cover-actions {
  margin-top: 28px;
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  min-width: 120px;
  padding: 12px 20px;
  border-radius: 2px;
  border: 1px solid transparent;
  transition: transform 0.15s ease, background 0.15s ease;
}
.btn:active { transform: scale(0.98); }
.btn.primary {
  background: var(--accent);
  color: #f7faf8;
}
.btn.ghost {
  border-color: currentColor;
  opacity: 0.9;
}
.cover-card .btn.primary { background: #2f6f5e; }
.cover-card .btn.ghost {
  border-color: rgba(242, 240, 234, 0.45);
  color: #f2f0ea;
}
.btn.full { width: 100%; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: grid;
  grid-template-columns: 44px 1fr 44px;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.topbar-title {
  text-align: center;
  font-size: 14px;
  color: var(--ink-soft);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.icon-btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  font-size: 18px;
}
.icon-btn:hover { background: var(--line); }

.view-toc { min-height: 100vh; }
.toc-scroll {
  padding: 8px 16px calc(28px + var(--safe-b));
  max-width: 720px;
  margin: 0 auto;
}
.toc-vol {
  margin: 22px 0 10px;
  font-family: var(--font-display);
  font-size: 20px;
  letter-spacing: 0.08em;
  color: var(--accent);
}
.toc-item {
  width: 100%;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  text-align: left;
  padding: 14px 12px;
  border-bottom: 1px solid var(--line);
  color: var(--ink);
}
.toc-item:hover { background: color-mix(in srgb, var(--accent) 8%, transparent); }
.toc-item.active {
  color: var(--accent);
  font-weight: 600;
}
.toc-item .num {
  flex: 0 0 auto;
  color: var(--ink-soft);
  font-variant-numeric: tabular-nums;
}

.view-reader { min-height: 100vh; padding-bottom: var(--safe-b); }
.reader-sheet {
  max-width: 720px;
  margin: 0 auto;
  padding: 8px 20px 48px;
}
.chapter-head { margin: 18px 0 28px; }
.chapter-vol {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--accent);
}
.chapter-name {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: clamp(26px, 6vw, 34px);
  font-weight: 400;
  letter-spacing: 0.06em;
  line-height: 1.35;
}
.chapter-meta {
  margin-top: 14px;
  padding: 12px 14px;
  border-left: 3px solid var(--accent-2);
  background: color-mix(in srgb, var(--card) 80%, transparent);
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-soft);
}
.chapter-meta:empty { display: none; }

.chapter-body {
  font-size: var(--fs);
  line-height: var(--lh);
  letter-spacing: 0.02em;
  text-align: justify;
  word-break: break-word;
}
.chapter-body p {
  margin: 0 0 1.05em;
  text-indent: 2em;
}
.chapter-body p.center {
  text-indent: 0;
  text-align: center;
  color: var(--ink-soft);
}

.video-notes {
  margin: 36px 0 20px;
  border: 1px solid var(--line);
  padding: 8px 14px;
  background: var(--card);
}
.video-notes summary {
  cursor: pointer;
  color: var(--accent);
  padding: 8px 0;
}
.video-notes pre {
  margin: 0 0 10px;
  white-space: pre-wrap;
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.chapter-nav {
  display: flex;
  gap: 12px;
  justify-content: space-between;
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.chapter-nav .btn { flex: 1; }

.progress-bar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  background: var(--line);
  z-index: 20;
}
.progress-bar span {
  display: block;
  height: 100%;
  width: 0;
  background: var(--accent);
  transition: width 0.2s ease;
}

.settings {
  position: fixed;
  inset: 0;
  z-index: 40;
  background: rgba(0, 0, 0, 0.35);
  display: grid;
  align-items: end;
}
.settings-panel {
  background: var(--card);
  color: var(--ink);
  padding: 22px 20px calc(22px + var(--safe-b));
  border-radius: 16px 16px 0 0;
  box-shadow: var(--shadow);
}
.settings-panel h3 {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-weight: 400;
}
.setting-row {
  display: grid;
  grid-template-columns: 48px 1fr;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
  font-size: 14px;
}
.theme-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin: 8px 0 20px;
  font-size: 14px;
}
.theme-picks { display: flex; gap: 8px; }
.theme-btn {
  width: 44px;
  height: 36px;
  border: 1px solid var(--line);
  border-radius: 4px;
}
.theme-btn[data-theme="paper"] { background: #e8e4dc; color: #1c2420; }
.theme-btn[data-theme="night"] { background: #12171a; color: #e7ebe8; }
.theme-btn[data-theme="ash"] { background: #cfd4d6; color: #22282b; }

@media (min-width: 860px) {
  .reader-sheet { padding-top: 16px; }
  .settings { align-items: center; justify-items: center; }
  .settings-panel {
    width: min(420px, 92vw);
    border-radius: 12px;
    padding-bottom: 22px;
  }
}