/* ============ 设计令牌 ============ */
:root {
  --bg: #ffffff;
  --bg-soft: #faf9f7;
  --bg-sunk: #f2f1ee;
  --fg: #1a1a1a;
  --fg-soft: #4a4a4a;
  --muted: #6f6f6f;
  --border: #e6e4e0;
  --border-strong: #d4d1cc;
  --accent: #c0522a;
  --accent-fg: #ffffff;
  --accent-soft: #fbf0ea;
  --danger: #b3261e;
  --ok: #1f7a43;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --w: 720px;
  --radius: 10px;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 8px 24px rgba(0, 0, 0, 0.05);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #131312;
    --bg-soft: #1a1a19;
    --bg-sunk: #202020;
    --fg: #ececea;
    --fg-soft: #cdcdc9;
    --muted: #9a9a95;
    --border: #2e2e2c;
    --border-strong: #3d3d3a;
    --accent: #e8794a;
    --accent-fg: #1a1a1a;
    --accent-soft: #2a1d17;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.35);
  }
}

/* ============ 基础 ============ */
*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: inherit; }
img { max-width: 100%; height: auto; }
/* 浏览器默认给 form 加 16px 下外边距，会让表单参与 flex 布局时错位 */
form { margin: 0; }
hr { border: 0; border-top: 1px solid var(--border); margin: 40px 0; }

.hp { position: absolute; left: -9999px; width: 1px; height: 1px; opacity: 0; }

/* ============ 头部 ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.site-header-inner {
  max-width: var(--w);
  margin: 0 auto;
  padding: 0 20px;
  height: 58px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 9px;
  text-decoration: none;
  font-weight: 700;
  font-size: 16px;
  letter-spacing: -0.01em;
  min-width: 0;
}
.brand-logo { width: 26px; height: 26px; border-radius: 50%; object-fit: cover; flex: none; }
.brand-name { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

.site-nav { display: flex; align-items: center; gap: 18px; flex: none; }
.site-nav a { text-decoration: none; font-size: 14.5px; color: var(--fg-soft); }
.site-nav a:hover { color: var(--fg); }

/* ============ 主体容器 ============ */
.main {
  max-width: var(--w);
  margin: 0 auto;
  padding: 0 20px 80px;
}
.main.wide { max-width: 1040px; }

/* ============ 按钮 ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 18px;
  border: 1px solid transparent;
  border-radius: 6px;
  font: inherit;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.2;
  text-decoration: none;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.15s, border-color 0.15s, opacity 0.15s;
}
.btn-accent { background: var(--accent); color: var(--accent-fg); }
.btn-accent:hover { opacity: 0.88; }
.btn-ghost { background: transparent; border-color: var(--border-strong); color: var(--fg); }
.btn-ghost:hover { background: var(--bg-soft); }
.btn-danger { background: transparent; border-color: var(--border-strong); color: var(--danger); }
.btn-danger:hover { background: var(--accent-soft); }
.btn-sm { padding: 7px 14px; font-size: 14px; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

/* ============ 首页 Hero ============ */
.hero {
  text-align: center;
  padding: 64px 0 48px;
  border-bottom: 1px solid var(--border);
}
.hero-logo {
  width: 88px;
  height: 88px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto 24px;
  display: block;
  box-shadow: var(--shadow);
}
.hero-title {
  margin: 0 0 14px;
  font-size: clamp(30px, 6vw, 44px);
  line-height: 1.15;
  font-weight: 800;
  letter-spacing: -0.025em;
}
.hero-tagline {
  margin: 0 auto 18px;
  max-width: 34em;
  font-size: 17.5px;
  line-height: 1.6;
  color: var(--muted);
}
.hero-byline {
  margin: 0 0 28px;
  font-size: 14px;
  color: var(--muted);
  display: flex;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
}
.hero-byline span + span::before { content: "·"; margin-right: 8px; }
.hero-note { margin: 18px 0 0; font-size: 13px; color: var(--muted); }

/* ============ 订阅表单 ============ */
.subscribe-form {
  display: flex;
  gap: 8px;
  max-width: 460px;
  margin: 0 auto;
  flex-wrap: wrap;
  position: relative;
}
.subscribe-form input[type="email"] {
  flex: 1 1 220px;
  min-width: 0;
  padding: 11px 14px;
  font: inherit;
  font-size: 15px;
  color: var(--fg);
  background: var(--bg);
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  outline: none;
}
.subscribe-form input[type="email"]:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.subscribe-form .btn { flex: 0 0 auto; }
.form-msg {
  flex-basis: 100%;
  margin: 4px 0 0;
  font-size: 14px;
  text-align: center;
  color: var(--ok);
}
.form-msg.error { color: var(--danger); }

/* ============ 文章列表 ============ */
.post-list { display: flex; flex-direction: column; }
.post-row {
  display: flex;
  align-items: flex-start;
  gap: 24px;
  padding: 26px 0;
  border-bottom: 1px solid var(--border);
}
.post-row:last-child { border-bottom: 0; }
.post-row-main { flex: 1 1 auto; min-width: 0; text-decoration: none; display: block; }
.post-row-title {
  margin: 0 0 7px;
  font-size: 20px;
  line-height: 1.35;
  font-weight: 700;
  letter-spacing: -0.015em;
}
.post-row-main:hover .post-row-title { color: var(--accent); }
.post-row-excerpt {
  margin: 0 0 9px;
  font-size: 15px;
  line-height: 1.6;
  color: var(--muted);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.post-row-meta { margin: 0; font-size: 13px; color: var(--muted); }
.post-row-thumb { flex: 0 0 152px; display: block; }
.post-row-thumb img {
  width: 152px;
  height: 102px;
  object-fit: cover;
  border-radius: 6px;
  display: block;
  background: var(--bg-sunk);
}

.month-group { padding-top: 22px; }
.month-label {
  margin: 0;
  padding-bottom: 6px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--muted);
}
.more-link { margin: 28px 0 0; font-size: 15px; }
.more-link a { color: var(--accent); text-decoration: none; font-weight: 600; }

.page-head { padding: 48px 0 8px; border-bottom: 1px solid var(--border); }
.page-head h1 { margin: 0 0 6px; font-size: 32px; font-weight: 800; letter-spacing: -0.02em; }
.page-head p { margin: 0; color: var(--muted); font-size: 14.5px; }

.empty { padding: 48px 0; color: var(--muted); text-align: center; }

/* ============ 文章页 ============ */
.post { padding: 52px 0 0; }
.post-head { margin-bottom: 30px; }
.post-title {
  margin: 0 0 12px;
  font-size: clamp(28px, 5.2vw, 40px);
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: -0.025em;
}
.post-subtitle { margin: 0 0 16px; font-size: 19px; line-height: 1.5; color: var(--muted); }
.post-meta { margin: 0; font-size: 14px; color: var(--muted); display: flex; gap: 8px; flex-wrap: wrap; }
.post-meta span + span::before { content: "·"; margin-right: 8px; }
.post-cover { width: 100%; border-radius: 8px; margin: 0 0 34px; display: block; }

.post-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 48px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}
.post-nav-item { text-decoration: none; display: block; min-width: 0; }
.post-nav-item span { display: block; font-size: 13px; color: var(--muted); margin-bottom: 4px; }
.post-nav-item strong { font-size: 15px; font-weight: 600; line-height: 1.4; }
.post-nav-item:hover strong { color: var(--accent); }
.post-nav-item.align-right { text-align: right; }

/* ============ 正文排版 ============ */
.prose { font-size: 17.5px; line-height: 1.78; color: var(--fg-soft); }
.prose > *:first-child { margin-top: 0; }
.prose p { margin: 0 0 1.3em; }
.prose h1, .prose h2, .prose h3, .prose h4 {
  color: var(--fg);
  font-weight: 700;
  letter-spacing: -0.015em;
  line-height: 1.32;
  scroll-margin-top: 76px;
  position: relative;
}
.prose h1 { font-size: 1.7em; margin: 2em 0 0.7em; }
.prose h2 { font-size: 1.42em; margin: 1.9em 0 0.65em; }
.prose h3 { font-size: 1.2em; margin: 1.7em 0 0.55em; }
.prose h4 { font-size: 1.05em; margin: 1.6em 0 0.5em; }
.prose .anchor {
  position: absolute;
  left: -0.75em;
  opacity: 0;
  text-decoration: none;
  color: var(--muted);
  font-weight: 400;
}
.prose h1:hover .anchor, .prose h2:hover .anchor,
.prose h3:hover .anchor, .prose h4:hover .anchor { opacity: 0.5; }
.prose a { color: var(--accent); text-decoration: underline; text-underline-offset: 2px; }
.prose strong { color: var(--fg); font-weight: 700; }
.prose ul, .prose ol { margin: 0 0 1.3em; padding-left: 1.5em; }
.prose li { margin-bottom: 0.45em; }
.prose li > ul, .prose li > ol { margin: 0.45em 0 0; }
.prose blockquote {
  margin: 1.6em 0;
  padding: 2px 0 2px 1.1em;
  border-left: 3px solid var(--border-strong);
  color: var(--muted);
}
.prose blockquote p:last-child { margin-bottom: 0; }
.prose code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--bg-sunk);
  padding: 2px 5px;
  border-radius: 4px;
}
.prose pre {
  margin: 0 0 1.5em;
  padding: 16px 18px;
  background: var(--bg-sunk);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow-x: auto;
}
.prose pre code { background: none; padding: 0; font-size: 14px; line-height: 1.65; }
.prose figure { margin: 1.8em 0; }
.prose figure img { width: 100%; border-radius: 8px; display: block; }
.prose figcaption { margin-top: 8px; font-size: 13.5px; color: var(--muted); text-align: center; }
.prose img { border-radius: 8px; }
.prose table { width: 100%; border-collapse: collapse; margin: 0 0 1.5em; font-size: 15px; display: block; overflow-x: auto; }
.prose th, .prose td { border: 1px solid var(--border); padding: 8px 12px; text-align: left; }
.prose th { background: var(--bg-soft); font-weight: 600; }
.prose hr { margin: 2.4em 0; }

/* ============ CTA / 提示 ============ */
.cta-card {
  margin: 56px 0 0;
  padding: 36px 28px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-align: center;
}
.cta-card h2 { margin: 0 0 8px; font-size: 22px; font-weight: 700; letter-spacing: -0.02em; }
.cta-card > p { margin: 0 auto 20px; max-width: 32em; color: var(--muted); font-size: 15px; }
.cta-note { margin: 16px 0 0 !important; font-size: 13px; }

.banner {
  margin: 20px 0 0;
  padding: 11px 16px;
  background: var(--accent-soft);
  border: 1px solid var(--accent);
  border-radius: 6px;
  font-size: 14px;
  color: var(--fg);
}
.banner a { margin-left: 8px; color: var(--accent); font-weight: 600; }

.message { padding: 80px 0; text-align: center; }
.message h1 { margin: 0 0 12px; font-size: 28px; font-weight: 700; }
.message p { margin: 0 0 20px; color: var(--muted); font-size: 16px; }
.message.warn h1 { color: var(--danger); }

/* ============ 页脚 ============ */
.site-footer { border-top: 1px solid var(--border); background: var(--bg-soft); }
.site-footer-inner {
  max-width: var(--w);
  margin: 0 auto;
  padding: 36px 20px 44px;
  text-align: center;
}
.footer-title { margin: 0 0 12px; font-weight: 700; font-size: 15px; }
.footer-links { margin: 0 0 10px; display: flex; justify-content: center; gap: 18px; flex-wrap: wrap; }
.footer-links a { font-size: 14px; color: var(--muted); text-decoration: none; }
.footer-links a:hover { color: var(--fg); }
.footer-meta { margin: 0; font-size: 13px; color: var(--muted); }
.footer-meta a { color: var(--muted); }

/* ============ 移动端 ============ */
@media (max-width: 640px) {
  .site-nav { gap: 14px; }
  .hero { padding: 44px 0 36px; }
  .hero-logo { width: 72px; height: 72px; }
  .subscribe-form { flex-direction: column; }
  .subscribe-form .btn { width: 100%; }
  .post-row { gap: 14px; padding: 20px 0; }
  .post-row-thumb { flex-basis: 96px; }
  .post-row-thumb img { width: 96px; height: 72px; }
  .post-row-title { font-size: 17.5px; }
  .post-row-excerpt { font-size: 14px; -webkit-line-clamp: 2; }
  .prose { font-size: 16.5px; }
  .post-nav { grid-template-columns: 1fr; }
  .post-nav-item.align-right { text-align: left; }
  .cta-card { padding: 28px 20px; }
}