/* ===========================================================
   哲思 · 个人哲学博客  样式表
   改颜色只需要动下面 :root 里的几个值
   =========================================================== */

:root {
  --paper:      #f7f4ee;   /* 页面底色，像纸 */
  --paper-2:    #fffdf9;   /* 卡片底色 */
  --ink:        #22201d;   /* 正文颜色 */
  --ink-soft:   #5c5751;   /* 次要文字 */
  --ink-faint:  #9a938a;   /* 更淡的文字 */
  --line:       #e3ddd2;   /* 分割线 */
  --accent:     #8c5a34;   /* 主色：赭石 */
  --accent-2:   #2f5d62;   /* 副色：青灰 */
  --shadow:     0 1px 2px rgba(34,32,29,.04), 0 8px 30px rgba(34,32,29,.06);
  --radius:     14px;
  --serif:      "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", Georgia, "Times New Roman", serif;
  --sans:       "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", -apple-system, system-ui, sans-serif;
  --maxw:       1080px;
}

html[data-theme="dark"] {
  --paper:      #15171a;
  --paper-2:    #1c1f23;
  --ink:        #e7e3dc;
  --ink-soft:   #a9a29a;
  --ink-faint:  #6f6a63;
  --line:       #2c3034;
  --accent:     #d79a68;
  --accent-2:   #7fb2b6;
  --shadow:     0 1px 2px rgba(0,0,0,.2), 0 10px 34px rgba(0,0,0,.28);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.85;
  -webkit-font-smoothing: antialiased;
  transition: background .4s ease, color .4s ease;
  overflow-x: hidden;
}

/* 纸张纹理：极淡的噪点，让底色不那么"平" */
body::before {
  content: "";
  position: fixed; inset: 0;
  pointer-events: none;
  z-index: 0;
  opacity: .5;
  background-image: radial-gradient(rgba(140,90,52,.05) 1px, transparent 1px);
  background-size: 22px 22px;
}
html[data-theme="dark"] body::before { opacity: .35; background-image: radial-gradient(rgba(215,154,104,.06) 1px, transparent 1px); }

a { color: inherit; text-decoration: none; }

::selection { background: var(--accent); color: #fff; }

/* ---------- 阅读进度条 ---------- */
.progress-bar {
  position: fixed; top: 0; left: 0; right: 0;
  height: 3px; z-index: 60;
  background: transparent;
  opacity: 0; transition: opacity .3s;
}
.progress-bar.on { opacity: 1; }
.progress-bar span {
  display: block; height: 100%; width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  transition: width .12s linear;
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  gap: 20px;
  padding: 18px max(24px, calc((100vw - var(--maxw)) / 2));
  background: color-mix(in srgb, var(--paper) 82%, transparent);
  backdrop-filter: blur(12px) saturate(140%);
  border-bottom: 1px solid transparent;
  transition: border-color .3s, padding .3s;
}
.site-header.scrolled { border-bottom-color: var(--line); padding-top: 12px; padding-bottom: 12px; }

.logo { display: flex; align-items: center; gap: 11px; }
.logo-mark {
  width: 26px; height: 26px; border-radius: 50%;
  border: 1.5px solid var(--accent);
  position: relative; flex: none;
}
.logo-mark::after {
  content: ""; position: absolute;
  left: 50%; top: 0; bottom: 0; width: 50%;
  background: var(--accent);
  border-radius: 0 13px 13px 0;
  animation: yinyang 14s linear infinite;
  transform-origin: left center;
}
@keyframes yinyang { to { transform: rotate(360deg); } }
.logo-text { font-size: 19px; letter-spacing: .12em; font-weight: 600; }
.logo-text em {
  display: block; font-size: 10px; letter-spacing: .3em;
  color: var(--ink-faint); font-style: normal; font-family: var(--sans);
  text-transform: uppercase; margin-top: -2px;
}

.nav { display: flex; align-items: center; gap: 6px; }
.nav a {
  font-family: var(--sans); font-size: 14px;
  padding: 7px 14px; border-radius: 999px;
  color: var(--ink-soft);
  transition: color .25s, background .25s;
}
.nav a:hover { color: var(--ink); background: color-mix(in srgb, var(--accent) 10%, transparent); }
.nav a.active { color: var(--accent); background: color-mix(in srgb, var(--accent) 12%, transparent); }

.nav a { white-space: nowrap; }

/* 手机上导航要放得下，不能折行 */
@media (max-width: 520px) {
  .site-header { padding-left: 16px; padding-right: 16px; gap: 8px; }
  .logo-text { font-size: 17px; letter-spacing: .06em; }
  .logo-text em { font-size: 9px; letter-spacing: .2em; }
  .logo-mark { width: 22px; height: 22px; }
  .nav { gap: 0; }
  .nav a { padding: 6px 8px; font-size: 13px; }
  .theme-toggle { margin-left: 4px; width: 32px; height: 32px; }
  .hero { padding-top: 46px; }
  .wrap, .about, .article { padding-left: 18px; padding-right: 18px; }
  .card { padding: 22px 20px 18px; }
  .card .ribbon { display: none; }
  .card-meta { flex-wrap: wrap; gap: 6px 9px; }
  .card-meta .dot { display: none; }
  .card h2 { font-size: 20px; }
  body { font-size: 16.5px; }
  .prose { font-size: 16.5px; }
}

.theme-toggle {
  margin-left: 6px;
  width: 36px; height: 36px; flex: none;
  display: grid; place-items: center;
  border: 1px solid var(--line); border-radius: 50%;
  background: transparent; color: var(--ink-soft);
  cursor: pointer; transition: color .25s, border-color .25s, transform .4s;
}
.theme-toggle:hover { color: var(--accent); border-color: var(--accent); transform: rotate(25deg); }
.theme-toggle svg { fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; }
.theme-toggle .icon-moon { display: none; }
html[data-theme="dark"] .theme-toggle .icon-sun { display: none; }
html[data-theme="dark"] .theme-toggle .icon-moon { display: block; }

/* ---------- 通用容器 ---------- */
.wrap { position: relative; z-index: 1; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- 首页 Hero ---------- */
.hero { position: relative; padding: 78px 0 54px; overflow: hidden; }
.hero-inner { position: relative; z-index: 2; max-width: 660px; }
.hero .eyebrow {
  font-family: var(--sans); font-size: 12px; letter-spacing: .34em;
  color: var(--accent); text-transform: uppercase; margin: 0 0 18px;
}
.hero h1 {
  font-size: clamp(34px, 6vw, 58px);
  line-height: 1.25; margin: 0 0 22px; font-weight: 600;
  letter-spacing: .01em;
}
.hero h1 .stroke { color: transparent; -webkit-text-stroke: 1px var(--accent); }
.hero p.lead { font-size: 18px; color: var(--ink-soft); margin: 0 0 30px; }

/* 会自己换的一句格言 */
.rotator {
  min-height: 64px;
  border-left: 2px solid var(--accent);
  padding: 4px 0 4px 18px;
  font-size: 16px; color: var(--ink-soft);
}
.rotator .q { display: block; transition: opacity .6s, transform .6s; }
.rotator .q.out { opacity: 0; transform: translateY(-8px); }
.rotator .who { font-family: var(--sans); font-size: 12.5px; color: var(--ink-faint); }

/* 背景里缓慢漂浮的圆环 */
.orbits { position: absolute; inset: 0; z-index: 1; pointer-events: none; }
.orbit {
  position: absolute; border-radius: 50%;
  border: 1px solid color-mix(in srgb, var(--accent) 22%, transparent);
  animation: float 20s ease-in-out infinite;
}
.orbit:nth-child(1) { width: 300px; height: 300px; right: -60px;  top: 10px;  }
.orbit:nth-child(2) { width: 190px; height: 190px; right: 150px; top: 150px; animation-delay: -6s; border-style: dashed; }
.orbit:nth-child(3) { width: 96px;  height: 96px;  right: 60px;  top: 280px; animation-delay: -12s;
  background: radial-gradient(circle at 34% 30%, color-mix(in srgb, var(--accent) 26%, transparent), transparent 68%); border: none; }
@keyframes float {
  0%,100% { transform: translate(0,0) scale(1); }
  33%     { transform: translate(-16px, 20px) scale(1.04); }
  66%     { transform: translate(12px, -14px) scale(.97); }
}
@media (max-width: 760px) { .orbits { opacity: .45; } }

/* ---------- 搜索 + 标签筛选 ---------- */
.filters {
  display: flex; flex-wrap: wrap; align-items: center; gap: 12px;
  padding: 22px 0 8px;
  border-top: 1px solid var(--line);
  margin-top: 16px;
}
.search-box { position: relative; flex: 1 1 240px; max-width: 320px; }
.search-box input {
  width: 100%; padding: 10px 14px 10px 38px;
  font-family: var(--sans); font-size: 14px;
  color: var(--ink); background: var(--paper-2);
  border: 1px solid var(--line); border-radius: 999px;
  outline: none; transition: border-color .25s, box-shadow .25s;
}
.search-box input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 14%, transparent); }
.search-box svg { position: absolute; left: 13px; top: 50%; transform: translateY(-50%); stroke: var(--ink-faint); fill: none; stroke-width: 1.8; }

.tags { display: flex; flex-wrap: wrap; gap: 7px; }
.tag {
  font-family: var(--sans); font-size: 12.5px;
  padding: 5px 12px; border-radius: 999px;
  border: 1px solid var(--line); color: var(--ink-soft);
  background: transparent; cursor: pointer;
  transition: all .22s;
}
.tag:hover { border-color: var(--accent); color: var(--accent); }
.tag.active { background: var(--accent); border-color: var(--accent); color: #fff; }

.result-count { font-family: var(--sans); font-size: 13px; color: var(--ink-faint); padding: 14px 0 0; }

/* ---------- 文章列表 ---------- */
.post-list { display: grid; gap: 18px; padding: 18px 0 70px; }
@media (min-width: 860px) { .post-list { grid-template-columns: 1fr 1fr; } }

.card {
  position: relative;
  display: flex; flex-direction: column;
  padding: 26px 26px 22px;
  background: var(--paper-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform .35s cubic-bezier(.2,.7,.3,1), box-shadow .35s, border-color .35s;
}
.card::before {
  content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 3px;
  background: linear-gradient(var(--accent), var(--accent-2));
  transform: scaleY(0); transform-origin: top; transition: transform .4s;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: color-mix(in srgb, var(--accent) 35%, var(--line)); }
.card:hover::before { transform: scaleY(1); }

.card.featured { grid-column: 1 / -1; }
.card.featured h2 { font-size: clamp(24px, 3.4vw, 32px); }
.card.featured .card-excerpt { font-size: 17px; }
.card .ribbon {
  position: absolute; right: 18px; top: 18px;
  font-family: var(--sans); font-size: 11px; letter-spacing: .18em;
  color: var(--accent); border: 1px solid color-mix(in srgb, var(--accent) 45%, transparent);
  padding: 3px 9px; border-radius: 999px;
}

.card-meta {
  font-family: var(--sans); font-size: 12px; color: var(--ink-faint);
  display: flex; gap: 10px; align-items: center; margin-bottom: 10px;
}
.card-meta .dot { width: 3px; height: 3px; border-radius: 50%; background: currentColor; }
.card-school { color: var(--accent-2); }
.card h2 { font-size: 22px; line-height: 1.45; margin: 0 0 10px; font-weight: 600; }
.card-excerpt { margin: 0 0 18px; color: var(--ink-soft); font-size: 15.5px; flex: 1; }
.card-foot { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.chip {
  font-family: var(--sans); font-size: 11.5px;
  padding: 3px 9px; border-radius: 6px;
  background: color-mix(in srgb, var(--accent) 9%, transparent);
  color: var(--accent);
}
.card-more { margin-left: auto; font-family: var(--sans); font-size: 13px; color: var(--accent); }
.card-more::after { content: " →"; transition: margin .25s; display: inline-block; }
.card:hover .card-more::after { margin-left: 5px; }

/* 出场动画：滚动到视口内才浮现 */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s cubic-bezier(.2,.7,.3,1); }
.reveal.in { opacity: 1; transform: none; }

.empty { padding: 60px 0 90px; text-align: center; color: var(--ink-faint); font-family: var(--sans); }

/* ---------- 文章详情页 ---------- */
.article { position: relative; z-index: 1; max-width: 1080px; margin: 0 auto; padding: 44px 24px 80px; }
.back-link { font-family: var(--sans); font-size: 13.5px; color: var(--ink-soft); }
.back-link:hover { color: var(--accent); }

.article-head { max-width: 720px; margin: 26px 0 40px; }
.article-head .kicker { font-family: var(--sans); font-size: 12px; letter-spacing: .28em; color: var(--accent); text-transform: uppercase; }
.article-head h1 { font-size: clamp(28px, 5vw, 44px); line-height: 1.3; margin: 14px 0 16px; font-weight: 600; }
.article-head .sub { font-size: 17.5px; color: var(--ink-soft); margin: 0 0 18px; }
.article-head .meta { font-family: var(--sans); font-size: 13px; color: var(--ink-faint); display: flex; flex-wrap: wrap; gap: 14px; }

.article-body-wrap { display: grid; gap: 46px; }
@media (min-width: 1000px) { .article-body-wrap { grid-template-columns: minmax(0,1fr) 210px; } }

.prose { max-width: 720px; font-size: 17.5px; }
.prose h2 {
  font-size: 25px; margin: 52px 0 16px; font-weight: 600;
  padding-left: 14px; border-left: 3px solid var(--accent);
  scroll-margin-top: 90px;
}
.prose h3 { font-size: 19.5px; margin: 34px 0 10px; color: var(--accent-2); }
.prose p { margin: 0 0 20px; }
.prose strong { color: var(--ink); font-weight: 700; background: linear-gradient(transparent 62%, color-mix(in srgb, var(--accent) 22%, transparent) 62%); }
.prose em { font-style: italic; color: var(--accent-2); }
.prose ul, .prose ol { margin: 0 0 22px; padding-left: 24px; }
.prose li { margin-bottom: 9px; }
.prose li::marker { color: var(--accent); }
.prose hr { border: none; border-top: 1px solid var(--line); margin: 42px 0; }
.prose a.ref { color: var(--accent-2); border-bottom: 1px dashed currentColor; }
.prose a.ref:hover { color: var(--accent); }

.prose blockquote {
  margin: 30px 0; padding: 20px 24px;
  background: color-mix(in srgb, var(--accent) 6%, var(--paper-2));
  border-left: 3px solid var(--accent);
  border-radius: 0 10px 10px 0;
  font-size: 17px; color: var(--ink-soft);
}
.prose blockquote p:last-child { margin: 0; }
.prose blockquote cite { display: block; margin-top: 8px; font-family: var(--sans); font-size: 12.5px; font-style: normal; color: var(--ink-faint); }

/* 正文里的表格 */
.table-wrap { overflow-x: auto; margin: 26px 0; border: 1px solid var(--line); border-radius: 10px; }
.prose table { width: 100%; border-collapse: collapse; font-size: 15.5px; }
.prose th, .prose td { padding: 11px 15px; text-align: left; border-bottom: 1px solid var(--line); }
.prose thead th { font-family: var(--sans); font-size: 13px; color: var(--accent); background: color-mix(in srgb, var(--accent) 7%, transparent); }
.prose tbody tr:last-child td { border-bottom: none; }
.prose td:first-child { color: var(--ink-soft); }

/* 侧边目录 */
.toc { position: sticky; top: 92px; align-self: start; font-family: var(--sans); }
@media (max-width: 999px) { .toc { display: none; } }
.toc-title { font-size: 11.5px; letter-spacing: .24em; color: var(--ink-faint); text-transform: uppercase; margin-bottom: 12px; }
.toc a {
  display: block; font-size: 13.5px; line-height: 1.5;
  padding: 7px 0 7px 13px; color: var(--ink-soft);
  border-left: 2px solid var(--line);
  transition: color .25s, border-color .25s;
}
.toc a:hover { color: var(--accent); }
.toc a.active { color: var(--accent); border-left-color: var(--accent); }

/* 文末 */
.takeaway {
  max-width: 720px; margin: 56px 0 0; padding: 24px 26px;
  border: 1px dashed color-mix(in srgb, var(--accent) 45%, transparent);
  border-radius: var(--radius);
  background: color-mix(in srgb, var(--accent) 5%, transparent);
}
.takeaway h4 { font-family: var(--sans); font-size: 12.5px; letter-spacing: .2em; color: var(--accent); margin: 0 0 12px; text-transform: uppercase; }
.takeaway ul { margin: 0; padding-left: 20px; }
.takeaway li { margin-bottom: 8px; color: var(--ink-soft); }

.sources { max-width: 720px; margin-top: 34px; font-family: var(--sans); font-size: 13.5px; color: var(--ink-faint); }
.sources h4 { font-size: 12.5px; letter-spacing: .2em; text-transform: uppercase; margin: 0 0 10px; color: var(--ink-soft); }
.sources li { margin-bottom: 6px; }
.sources a { color: var(--accent-2); }
.sources a:hover { text-decoration: underline; }

.post-nav { display: grid; gap: 14px; max-width: 720px; margin-top: 52px; padding-top: 26px; border-top: 1px solid var(--line); }
@media (min-width: 620px) { .post-nav { grid-template-columns: 1fr 1fr; } }
.post-nav a {
  padding: 16px 18px; border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--paper-2); transition: border-color .3s, transform .3s;
}
.post-nav a:hover { border-color: var(--accent); transform: translateY(-2px); }
.post-nav span { display: block; font-family: var(--sans); font-size: 11.5px; color: var(--ink-faint); margin-bottom: 5px; }
.post-nav strong { font-weight: 600; font-size: 15.5px; }
.post-nav a.next { text-align: right; }

/* ---------- 主题页 ---------- */
.page-head { padding: 62px 0 26px; max-width: 640px; }
.page-head h1 { font-size: clamp(30px, 5vw, 42px); margin: 0 0 14px; font-weight: 600; }
.page-head p { color: var(--ink-soft); margin: 0; }

.school-grid { display: grid; gap: 18px; padding: 16px 0 80px; }
@media (min-width: 760px) { .school-grid { grid-template-columns: 1fr 1fr; } }
.school {
  padding: 26px; border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--paper-2); transition: transform .35s, box-shadow .35s;
}
.school:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.school .idx { font-family: var(--sans); font-size: 12px; color: var(--accent); letter-spacing: .2em; }
.school h3 { font-size: 21px; margin: 8px 0 10px; }
.school p { color: var(--ink-soft); font-size: 15.5px; margin: 0 0 16px; }
.school .links { display: flex; flex-direction: column; gap: 7px; }
.school .links a { font-family: var(--sans); font-size: 14px; color: var(--accent-2); }
.school .links a:hover { color: var(--accent); }
.school .links a::before { content: "— "; color: var(--ink-faint); }

/* ---------- 关于页 ---------- */
.about { max-width: 720px; padding: 62px 24px 90px; margin: 0 auto; position: relative; z-index: 1; }
.about h1 { font-size: clamp(30px, 5vw, 42px); margin: 0 0 22px; font-weight: 600; }
.about p { color: var(--ink-soft); margin: 0 0 20px; font-size: 17.5px; }
.about .signature { font-size: 15px; color: var(--ink-faint); font-family: var(--sans); margin-top: 34px; }
.about .creed { display: grid; gap: 14px; margin: 30px 0; }
.about .creed div { padding: 16px 20px; border-left: 2px solid var(--accent); background: color-mix(in srgb, var(--accent) 5%, transparent); }
.about .creed b { display: block; margin-bottom: 4px; }

/* ---------- 页脚 ---------- */
.site-footer { position: relative; z-index: 1; border-top: 1px solid var(--line); padding: 38px 24px 46px; }
.footer-inner { max-width: var(--maxw); margin: 0 auto; text-align: center; }
.footer-quote { font-size: 16px; color: var(--ink-soft); margin: 0 0 10px; }
.footer-meta { font-family: var(--sans); font-size: 12.5px; color: var(--ink-faint); margin: 0; }

/* 回到顶部 */
.to-top {
  position: fixed; right: 22px; bottom: 26px; z-index: 40;
  width: 42px; height: 42px; border-radius: 50%;
  display: grid; place-items: center;
  background: var(--paper-2); color: var(--ink-soft);
  border: 1px solid var(--line); cursor: pointer;
  opacity: 0; transform: translateY(12px); pointer-events: none;
  transition: all .3s; box-shadow: var(--shadow);
}
.to-top.on { opacity: 1; transform: none; pointer-events: auto; }
.to-top:hover { color: var(--accent); border-color: var(--accent); }
.to-top svg { fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; }

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition-duration: .01ms !important; }
  .reveal { opacity: 1; transform: none; }
}