/* ===== AI 使用手记 - 全站样式 ===== */
:root {
  --primary: #2f5f8f;
  --primary-dark: #23496c;
  --accent: #e8853d;
  --bg: #f7f8fa;
  --card: #ffffff;
  --text: #2b2f36;
  --text-light: #6b7280;
  --border: #e5e8ec;
  --radius: 10px;
  --max-width: 960px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.8;
  font-size: 16px;
}

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

img { max-width: 100%; }

/* ===== 顶部导航 ===== */
.site-header {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.logo {
  font-size: 20px;
  font-weight: 700;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo .logo-mark {
  width: 30px;
  height: 30px;
  background: var(--primary);
  color: #fff;
  border-radius: 8px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  font-weight: 700;
}

.logo:hover { color: var(--primary); }

.nav-links { display: flex; gap: 28px; }

.nav-links a {
  color: var(--text-light);
  font-size: 15px;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

/* ===== 通用容器 ===== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 40px 20px;
}

.page-title {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 8px;
}

.page-sub {
  color: var(--text-light);
  margin-bottom: 32px;
}

/* ===== 首页横幅 ===== */
.hero {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: #fff;
  padding: 72px 20px;
  text-align: center;
}

.hero-inner { max-width: 720px; margin: 0 auto; }

.hero h1 {
  font-size: 34px;
  margin-bottom: 16px;
  letter-spacing: 1px;
}

.hero p {
  font-size: 17px;
  opacity: .92;
  margin-bottom: 32px;
}

.hero .btn {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  padding: 12px 36px;
  border-radius: 999px;
  font-size: 16px;
  font-weight: 600;
  transition: opacity .2s;
}

.hero .btn:hover { opacity: .9; color: #fff; }

/* ===== 分类卡片 ===== */
.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 20px;
  margin-bottom: 48px;
}

.category-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: box-shadow .2s, transform .2s;
}

.category-card:hover {
  box-shadow: 0 8px 24px rgba(47, 95, 143, .12);
  transform: translateY(-2px);
}

.category-card .cat-icon {
  font-size: 28px;
  margin-bottom: 12px;
  display: block;
}

.category-card h3 { font-size: 17px; margin-bottom: 6px; }
.category-card p { font-size: 14px; color: var(--text-light); }

/* ===== 文章卡片 ===== */
.section-title {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.section-title .more { font-size: 14px; font-weight: 400; }

.article-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
  margin-bottom: 48px;
}

.article-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  display: flex;
  flex-direction: column;
  transition: box-shadow .2s, transform .2s;
}

.article-card:hover {
  box-shadow: 0 8px 24px rgba(47, 95, 143, .12);
  transform: translateY(-2px);
}

.article-card .tag {
  align-self: flex-start;
  font-size: 12px;
  color: var(--primary);
  background: rgba(47, 95, 143, .08);
  border-radius: 4px;
  padding: 2px 10px;
  margin-bottom: 12px;
}

.article-card h3 {
  font-size: 18px;
  line-height: 1.5;
  margin-bottom: 10px;
}

.article-card h3 a { color: var(--text); }
.article-card h3 a:hover { color: var(--primary); }

.article-card p {
  font-size: 14px;
  color: var(--text-light);
  flex: 1;
}

.article-card .meta {
  margin-top: 16px;
  font-size: 13px;
  color: #9aa1ab;
  display: flex;
  justify-content: space-between;
}

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

.list-item {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 26px;
  display: flex;
  align-items: flex-start;
  gap: 20px;
  transition: box-shadow .2s;
}

.list-item:hover { box-shadow: 0 6px 18px rgba(47, 95, 143, .1); }

.list-item .date-box {
  flex-shrink: 0;
  text-align: center;
  background: rgba(47, 95, 143, .06);
  border-radius: 8px;
  padding: 8px 14px;
}

.list-item .date-box .d { font-size: 22px; font-weight: 700; color: var(--primary); line-height: 1.2; }
.list-item .date-box .m { font-size: 12px; color: var(--text-light); }

.list-item h2 { font-size: 18px; margin-bottom: 6px; line-height: 1.5; }
.list-item h2 a { color: var(--text); }
.list-item h2 a:hover { color: var(--primary); }
.list-item .desc { font-size: 14px; color: var(--text-light); }

.list-item .tag {
  display: inline-block;
  font-size: 12px;
  color: var(--primary);
  background: rgba(47, 95, 143, .08);
  border-radius: 4px;
  padding: 1px 8px;
  margin-left: 8px;
  vertical-align: 2px;
}

/* ===== 文章正文页 ===== */
.article-header {
  text-align: center;
  margin-bottom: 12px;
}

.article-header h1 {
  font-size: 28px;
  line-height: 1.5;
  margin: 12px 0;
}

.article-header .meta {
  font-size: 14px;
  color: var(--text-light);
}

.article-body {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 48px;
}

.article-body h2 {
  font-size: 21px;
  margin: 36px 0 14px;
  padding-left: 12px;
  border-left: 4px solid var(--primary);
}

.article-body h3 { font-size: 17px; margin: 26px 0 10px; }
.article-body p { margin-bottom: 14px; }
.article-body ul, .article-body ol { margin: 0 0 14px 24px; }
.article-body li { margin-bottom: 6px; }
.article-body strong { color: var(--primary-dark); }

.article-body blockquote {
  border-left: 4px solid var(--accent);
  background: rgba(232, 133, 61, .06);
  border-radius: 0 8px 8px 0;
  padding: 14px 20px;
  margin: 18px 0;
  color: #5b4a3a;
}

.article-body blockquote p { margin-bottom: 0; }

.article-body code {
  background: #eef1f5;
  border-radius: 4px;
  padding: 2px 8px;
  font-family: "SF Mono", Menlo, Consolas, monospace;
  font-size: 14px;
  color: var(--primary-dark);
}

.article-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 18px 0;
  font-size: 14px;
}

.article-body th, .article-body td {
  border: 1px solid var(--border);
  padding: 10px 14px;
  text-align: left;
}

.article-body th { background: rgba(47, 95, 143, .06); font-weight: 600; }

.article-nav {
  display: flex;
  justify-content: space-between;
  margin-top: 28px;
  gap: 16px;
}

.article-nav a {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 20px;
  font-size: 14px;
  color: var(--text);
  flex: 1;
}

.article-nav a:hover { border-color: var(--primary); color: var(--primary); }
.article-nav a.next { text-align: right; }
.article-nav a .label { display: block; font-size: 12px; color: var(--text-light); margin-bottom: 4px; }

/* ===== 关于页 ===== */
.about-content {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 48px;
}

.about-content h2 {
  font-size: 20px;
  margin: 30px 0 12px;
  padding-left: 12px;
  border-left: 4px solid var(--primary);
}

.about-content h2:first-child { margin-top: 0; }
.about-content p { margin-bottom: 12px; }

/* ===== 页脚 ===== */
.site-footer {
  background: #2b2f36;
  color: #9aa1ab;
  padding: 36px 20px;
  text-align: center;
  font-size: 13px;
  margin-top: 40px;
}

.site-footer p { margin-bottom: 6px; }
.site-footer a { color: #9aa1ab; }
.site-footer a:hover { color: #fff; }

.beian-links { display: flex; justify-content: center; gap: 24px; flex-wrap: wrap; }

/* ===== 响应式 ===== */
/* 平板 */
@media (max-width: 960px) {
  .hero { padding: 56px 20px; }
  .container { padding: 32px 16px; }
  .article-body, .about-content { padding: 32px 32px; }
}

/* 手机 */
@media (max-width: 640px) {
  .nav-wrap { padding: 0 14px; height: 56px; }
  .nav-links { gap: 16px; }
  .nav-links a { font-size: 14px; padding: 6px 0; }
  .logo { font-size: 18px; }
  .logo .logo-mark { width: 26px; height: 26px; font-size: 13px; }
  .hero { padding: 44px 16px; }
  .hero h1 { font-size: 24px; }
  .hero p { font-size: 15px; }
  .hero .btn { padding: 11px 28px; font-size: 15px; }
  .page-title { font-size: 24px; }
  .section-title { font-size: 19px; }
  .article-body, .about-content { padding: 24px 18px; }
  .article-body h1, .article-header h1 { font-size: 22px; }
  .article-body h2 { font-size: 18px; margin: 28px 0 12px; }
  .article-body table { display: block; overflow-x: auto; white-space: nowrap; -webkit-overflow-scrolling: touch; }
  .article-body code { font-size: 13px; word-break: break-all; }
  .list-item { flex-direction: column; gap: 12px; }
  .list-item .date-box { display: inline-block; padding: 6px 12px; }
  .article-nav { flex-direction: column; }
  .article-nav a.next { text-align: left; }
  .site-footer { padding: 28px 16px; }
  .beian-links { gap: 12px; }
  .beian-links a { padding: 4px 0; }
}

/* 超小屏 */
@media (max-width: 360px) {
  .nav-links { gap: 12px; }
  .category-grid { gap: 14px; }
  .article-grid { gap: 14px; }
}

/* 触控设备：放大可点击区域，避免审核手机端误触 */
@media (hover: none) {
  .nav-links a { padding: 8px 2px; }
  .article-nav a { padding: 14px 18px; }
}

/* 用户偏好减少动画时关闭过渡 */
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}