/* 外壳样式。只作用于首页/归档/标签/搜索——文章页自带样式，不受这里影响。 */

:root {
  --paper: #f6f3ec;
  --paper-2: #efeade;
  --ink: #16140f;
  --ink-2: #454034;
  --ink-3: #857e6c;
  --rule: #d9d2c1;
  --accent: #a3391d;
  --grain: 0.04;

  --serif: "Songti SC", "STSong", "Source Han Serif SC", "Noto Serif CJK SC",
    "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui,
    -apple-system, sans-serif;
  --mono: "SF Mono", "JetBrains Mono", "IBM Plex Mono", Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #100e0b;
    --paper-2: #171410;
    --ink: #ece6d9;
    --ink-2: #b8b1a1;
    --ink-3: #7d7768;
    --rule: #2b2721;
    --accent: #e0855c;
    --grain: 0.055;
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  padding: 0 clamp(1.25rem, 5vw, 3rem);
  background: var(--paper);
  color: var(--ink-2);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* 纸面颗粒：给纯色背景一点质感，不影响可读性 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  opacity: var(--grain);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.82' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

body > * { position: relative; z-index: 1; }

a { color: var(--accent); }

/* ── 页眉 ───────────────────────────────────────── */

.site-header {
  max-width: 54rem;
  margin: 0 auto;
  padding: clamp(3.5rem, 9vw, 6.5rem) 0 2rem;
  border-bottom: 3px double var(--rule);
  animation: rise 0.7s cubic-bezier(.2,.7,.3,1) both;
}

.site-title {
  display: inline-block;
  font-family: var(--serif);
  font-size: clamp(2.1rem, 6.5vw, 3.4rem);
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--ink);
  text-decoration: none;
}

.site-title:hover { color: var(--accent); }

.site-desc {
  margin: 0.7rem 0 0;
  max-width: 34rem;
  color: var(--ink-3);
  font-size: 0.95rem;
}

.site-header nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1.4rem;
  margin-top: 1.9rem;
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.site-header nav a {
  position: relative;
  color: var(--ink-3);
  text-decoration: none;
  padding-bottom: 2px;
}

.site-header nav a::after {
  content: "";
  position: absolute;
  left: 0; bottom: 0;
  width: 100%; height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.28s cubic-bezier(.2,.7,.3,1);
}

.site-header nav a:hover { color: var(--accent); }
.site-header nav a:hover::after { transform: scaleX(1); }

/* ── 主体 ───────────────────────────────────────── */

main {
  max-width: 54rem;
  margin: 0 auto;
  padding: 0 0 5rem;
}

h1 {
  font-family: var(--serif);
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin: 3rem 0 1.75rem;
}

/* 归档里的年份、标签页的分组标签 */
.section-label {
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  margin: 3.25rem 0 0.25rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--rule);
}

/* ── 文章档案列表 ────────────────────────────────── */

.posts {
  counter-reset: entry;
  list-style: none;
  margin: 0;
  padding: 0;
}

.posts li {
  counter-increment: entry;
  display: grid;
  /* minmax(0,1fr) 而非裸 1fr：1fr 的最小尺寸是 auto（由内容决定），
     不可断行的长内容会把列顶宽。这里是防御性写法，当前内容没有触发。 */
  grid-template-columns: 4.5rem minmax(0, 1fr);
  gap: 0 1.5rem;
  padding: 2.1rem 0;
  border-bottom: 1px solid var(--rule);
  animation: rise 0.65s cubic-bezier(.2,.7,.3,1) both;
}

.posts li:nth-child(1) { animation-delay: 0.06s; }
.posts li:nth-child(2) { animation-delay: 0.12s; }
.posts li:nth-child(3) { animation-delay: 0.18s; }
.posts li:nth-child(4) { animation-delay: 0.24s; }
.posts li:nth-child(n+5) { animation-delay: 0.3s; }

/* 左栏：档案序号 */
.posts li::before {
  content: counter(entry, decimal-leading-zero);
  grid-column: 1;
  grid-row: 1 / -1;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink-3);
  padding-top: 0.5rem;
  letter-spacing: 0.06em;
  transition: color 0.25s;
}

.posts li:hover::before { color: var(--accent); }

.posts h2 {
  grid-column: 2;
  margin: 0;
  font-size: 1rem; /* 实际字号由 a.title 决定，这里只是取消默认值 */
  font-weight: 400;
}

.posts a.title {
  font-family: var(--serif);
  font-size: clamp(1.18rem, 2.6vw, 1.45rem);
  font-weight: 600;
  line-height: 1.4;
  color: var(--ink);
  text-decoration: none;
  background-image: linear-gradient(var(--accent), var(--accent));
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 0% 1px;
  transition: background-size 0.35s cubic-bezier(.2,.7,.3,1), color 0.25s;
}

.posts li:hover a.title {
  color: var(--accent);
  background-size: 100% 1px;
}

.posts p {
  grid-column: 2;
  margin: 0.5rem 0 0;
  color: var(--ink-2);
  font-size: 0.94rem;
  max-width: 42rem;
}

.meta {
  grid-column: 2;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.55rem;
  margin-top: 0.85rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-3);
  letter-spacing: 0.04em;
}

.meta time { white-space: nowrap; }

/* 标签走无衬线：等宽字体会把中文字距拉开，排起来松散 */
.meta a {
  font-family: var(--sans);
  font-size: 0.76rem;
  letter-spacing: 0;
  color: var(--ink-3);
  text-decoration: none;
  border: 1px solid var(--rule);
  padding: 0.1rem 0.5rem;
  transition: border-color 0.2s, color 0.2s;
}

.meta a:hover { color: var(--accent); border-color: var(--accent); }

/* ── 标签索引 ───────────────────────────────────── */

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  padding: 0;
  margin: 0;
  list-style: none;
}

.tag-list a {
  display: inline-flex;
  align-items: baseline;
  gap: 0.45rem;
  padding: 0.4rem 0.85rem;
  border: 1px solid var(--rule);
  color: var(--ink);
  font-size: 0.9rem;
  text-decoration: none;
  transition: border-color 0.2s, color 0.2s, background 0.2s;
}

.tag-list a:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--paper-2);
}

.tag-list .count {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-3);
}

/* ── 页脚 / 空状态 ──────────────────────────────── */

.site-footer {
  max-width: 54rem;
  margin: 0 auto;
  padding: 2rem 0 3.5rem;
  border-top: 1px solid var(--rule);
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--ink-3);
}

.empty {
  color: var(--ink-3);
  font-size: 0.95rem;
  padding: 2rem 0;
  border-bottom: 1px solid var(--rule);
}

.back-link {
  display: inline-block;
  margin-top: 2.5rem;
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--ink-3);
  text-decoration: none;
}

.back-link:hover { color: var(--accent); }

/* ── Pagefind ───────────────────────────────────── */

#search {
  --pagefind-ui-primary: var(--accent);
  --pagefind-ui-text: var(--ink);
  --pagefind-ui-background: var(--paper);
  --pagefind-ui-border: var(--rule);
  --pagefind-ui-tag: var(--paper-2);
  --pagefind-ui-border-width: 1px;
  --pagefind-ui-border-radius: 0;
  --pagefind-ui-font: var(--sans);
}

/* ── 动效 ───────────────────────────────────────── */

@keyframes rise {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: none; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ── 窄屏 ───────────────────────────────────────── */

@media (max-width: 34rem) {
  .posts li {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
    padding: 1.75rem 0;
  }
  .posts li::before {
    grid-row: auto;
    grid-column: 1;
    padding-top: 0;
    margin-bottom: 0.35rem;
  }
  .posts h2, .posts p, .meta { grid-column: 1; }
  .site-header { padding-top: 3rem; }
}