/* ========== 主题变量 ========== */
:root {
  --bg: #fafafa;
  --bg-card: #ffffff;
  --text: #1a1a1a;
  --text-secondary: #666666;
  --accent: #4f6ef7;
  --accent-hover: #3b59e0;
  --border: #e5e5e5;
  --code-bg: #f3f4f6;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.06), 0 4px 14px rgba(0, 0, 0, 0.04);
  --radius: 12px;
}

html[data-theme="dark"] {
  --bg: #0f1115;
  --bg-card: #181b22;
  --text: #e8e8e8;
  --text-secondary: #9aa0a6;
  --accent: #7b93ff;
  --accent-hover: #96a9ff;
  --border: #2a2e37;
  --code-bg: #22262f;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.4), 0 4px 14px rgba(0, 0, 0, 0.3);
}

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

html {
  scroll-behavior: smooth;
  /* 首屏渲染前避免主题闪烁，由内联脚本提前设置 data-theme */
}

body {
  margin: 0;
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
    -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.75;
  transition: background 0.25s ease, color 0.25s ease;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container {
  width: 100%;
  max-width: 760px;
  margin: 0 auto;
  padding: 0 20px;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover { color: var(--accent-hover); text-decoration: underline; }

/* ========== 头部 ========== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.site-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text);
  letter-spacing: 0.05em;
}
.site-title:hover { text-decoration: none; color: var(--accent); }

.site-nav {
  display: flex;
  align-items: center;
  gap: 20px;
}
.site-nav a { color: var(--text-secondary); font-size: 0.95rem; }
.site-nav a:hover { color: var(--accent); text-decoration: none; }

.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  cursor: pointer;
  font-size: 1rem;
  padding: 4px 10px;
  color: var(--text);
  transition: border-color 0.2s;
}
.theme-toggle:hover { border-color: var(--accent); }

/* ========== 主体 ========== */
main { flex: 1; padding: 48px 0 64px; }

.hero { margin-bottom: 40px; }
.hero h1 {
  font-size: 1.9rem;
  margin: 0 0 8px;
  letter-spacing: 0.02em;
}
.hero p { color: var(--text-secondary); margin: 0; }

/* ========== 文章列表 ========== */
.post-list { display: flex; flex-direction: column; gap: 16px; }

.post-card {
  display: block;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 26px;
  box-shadow: var(--shadow);
  transition: transform 0.18s ease, border-color 0.18s ease;
  color: var(--text);
}
.post-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  text-decoration: none;
}
.post-card h2 {
  margin: 0 0 6px;
  font-size: 1.2rem;
  color: var(--text);
}
.post-card .post-meta {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 8px;
}
.post-card .post-summary {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.loading, .empty { color: var(--text-secondary); text-align: center; padding: 40px 0; }

/* ========== 文章正文 ========== */
.post { max-width: 720px; margin: 0 auto; }
.post-header { margin-bottom: 32px; }
.post-header h1 {
  font-size: 1.9rem;
  line-height: 1.35;
  margin: 0 0 10px;
}
.post-header .post-meta { color: var(--text-secondary); font-size: 0.9rem; }

.post-body h2 {
  margin-top: 2em;
  padding-bottom: 0.3em;
  border-bottom: 1px solid var(--border);
  font-size: 1.4rem;
}
.post-body h3 { margin-top: 1.6em; font-size: 1.15rem; }
.post-body p { margin: 1em 0; }
.post-body ul, .post-body ol { padding-left: 1.5em; }
.post-body li { margin: 0.35em 0; }
.post-body img { max-width: 100%; border-radius: 8px; }
.post-body blockquote {
  margin: 1.5em 0;
  padding: 4px 18px;
  border-left: 3px solid var(--accent);
  background: var(--code-bg);
  border-radius: 0 8px 8px 0;
  color: var(--text-secondary);
}
.post-body code {
  font-family: "JetBrains Mono", "Cascadia Code", Consolas, monospace;
  font-size: 0.88em;
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 5px;
}
.post-body pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  overflow-x: auto;
  line-height: 1.6;
}
.post-body pre code { background: none; padding: 0; }
.post-body hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2.5em 0;
}

.back-link {
  display: inline-block;
  margin-top: 40px;
  color: var(--text-secondary);
  font-size: 0.9rem;
}
.back-link:hover { color: var(--accent); }

/* ========== 页脚 ========== */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 24px 0;
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.85rem;
}
.site-footer p { margin: 0; }

/* ========== 响应式 ========== */
@media (max-width: 560px) {
  .hero h1 { font-size: 1.5rem; }
  .post-header h1 { font-size: 1.5rem; }
  .post-card { padding: 18px 20px; }
}