:root {
  --bg: #f5f5f3;
  --panel: #ffffff;
  --text: #1d1d1f;
  --muted: #61646b;
  --line: #dcdedf;
  --link: #0d5bd3;
  --reading-size: 1.16rem;
  --reading-line: 1.95;
}

:root[data-theme="dark"] {
  --bg: #111214;
  --panel: #1a1c20;
  --text: #e8e9ed;
  --muted: #adb3bc;
  --line: #32363c;
  --link: #8cb4ff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: radial-gradient(circle at top right, #eceeed 0%, var(--bg) 45%);
  color: var(--text);
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  line-height: 1.7;
}

a {
  color: var(--link);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.inner {
  width: min(920px, 92vw);
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}

.site-header .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 0;
}

.brand {
  font-weight: 700;
  color: var(--text);
}

.site-nav {
  display: flex;
  gap: 14px;
}

.main {
  min-height: calc(100vh - 130px);
  padding: 26px 0 40px;
}

.hero {
  padding: 14px 0 8px;
}

h1,
h2,
h3 {
  margin: 0 0 10px;
  line-height: 1.35;
}

section + section {
  margin-top: 30px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 14px;
}

.card,
.book-head,
.chapter-head,
.reading {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px;
}

.muted {
  color: var(--muted);
}

.small {
  color: var(--muted);
  font-size: 0.92rem;
}

.site-footer {
  padding: 24px 0 32px;
  color: var(--muted);
}

.update-list,
.toc {
  margin: 0;
  padding-left: 18px;
}

.update-list li,
.toc li {
  margin: 8px 0;
}

.update-list time {
  display: inline-block;
  min-width: 94px;
  color: var(--muted);
  font-size: 0.9rem;
}

.ghost-btn,
.reader-controls button,
.primary-btn {
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--text);
  border-radius: 10px;
  padding: 8px 12px;
  cursor: pointer;
}

.primary-btn {
  display: inline-block;
  margin-top: 8px;
}

.hidden {
  display: none;
}

.chapter-head {
  margin-bottom: 14px;
}

.reader-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 10px;
}

.reading {
  font-size: var(--reading-size);
  line-height: var(--reading-line);
  letter-spacing: 0.01em;
}

.reading p {
  margin: 0 0 1.1em;
  text-indent: 2em;
}

.reading h2,
.reading h3 {
  margin-top: 1.5em;
}

.chapter-nav {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  margin-top: 14px;
}

@media (max-width: 720px) {
  .site-header .inner {
    flex-wrap: wrap;
    justify-content: flex-start;
  }

  .site-nav {
    order: 3;
    width: 100%;
    margin-top: 4px;
  }

  .reading {
    font-size: calc(var(--reading-size) * 0.96);
  }
}