/* eis-w.com 全站样式表（双语，默认英文） */
:root {
  --primary: #7c3aed;
  --primary-dark: #6d28d9;
  --text: #1f2937;
  --text-light: #6b7280;
  --bg: #ffffff;
  --bg-soft: #f5f7fa;
  --border: #e5e7eb;
  --radius: 12px;
  --shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-hover: 0 6px 20px rgba(124, 58, 237, 0.15);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
}

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

.wrap { max-width: 1120px; margin: 0 auto; padding: 0 20px; }

/* ===== 头部 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}
.logo {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text);
}
.logo span { color: var(--primary); }
.logo:hover { color: var(--text); }

.site-nav { display: flex; gap: 4px; }
.site-nav a {
  padding: 6px 12px;
  border-radius: 8px;
  color: var(--text);
  font-size: 0.95rem;
  white-space: nowrap;
}
.site-nav a:hover { background: var(--bg-soft); color: var(--primary); }

/* checkbox 汉堡菜单（无 JS） */
.nav-toggle { display: none; }
.nav-burger {
  display: none;
  width: 40px;
  height: 40px;
  cursor: pointer;
  position: relative;
  border-radius: 8px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
}
.nav-burger span,
.nav-burger span::before,
.nav-burger span::after {
  display: block;
  position: absolute;
  width: 22px;
  height: 2px;
  background: var(--primary-dark);
  border-radius: 2px;
  transition: 0.25s;
}
.nav-burger span { top: 19px; left: 9px; }
.nav-burger span::before { content: ""; top: -7px; }
.nav-burger span::after { content: ""; top: 7px; }

@media (max-width: 860px) {
  .nav-burger { display: block; }
  .site-nav {
    display: none;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: 8px 20px 16px;
    gap: 2px;
    box-shadow: var(--shadow);
  }
  .site-nav a { padding: 10px 12px; }
  .nav-toggle:checked ~ .site-nav { display: flex; }
  .nav-toggle:checked ~ .nav-burger span { background: transparent; }
  .nav-toggle:checked ~ .nav-burger span::before { transform: rotate(45deg); top: 0; }
  .nav-toggle:checked ~ .nav-burger span::after { transform: rotate(-45deg); top: 0; }
}

/* ===== Hero ===== */
.hero {
  background: linear-gradient(135deg, #7c3aed 0%, #4f46e5 100%);
  color: #fff;
  padding: 72px 0;
  text-align: center;
}
.hero h1 { font-size: 2.3rem; letter-spacing: 1px; margin-bottom: 14px; }
.hero p {
  max-width: 640px;
  margin: 0 auto 28px;
  opacity: 0.92;
  font-size: 1.05rem;
}
.btn {
  display: inline-block;
  padding: 11px 26px;
  border-radius: 999px;
  background: #fff;
  color: var(--primary);
  font-weight: 600;
  margin: 0 6px 10px;
}
.btn:hover { background: #f5f3ff; color: var(--primary-dark); }
.btn-ghost {
  background: transparent;
  color: #fff;
  border: 1.5px solid rgba(255, 255, 255, 0.7);
}
.btn-ghost:hover { background: rgba(255, 255, 255, 0.12); color: #fff; }

/* ===== 区块与卡片 ===== */
.block { padding: 56px 0 8px; }
.block-title {
  font-size: 1.5rem;
  margin-bottom: 24px;
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}
.block-title small { font-size: 0.9rem; font-weight: 400; color: var(--text-light); }

.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
@media (max-width: 900px) { .grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 580px) { .grid { grid-template-columns: 1fr; } }

.card {
  display: block;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  color: var(--text);
  box-shadow: var(--shadow);
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
}
a.card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
  border-color: var(--primary);
  color: var(--text);
}
a.card:hover h3 { color: var(--primary); }
.card h3 { font-size: 1.08rem; margin-bottom: 8px; transition: color 0.2s; }
.card p { font-size: 0.92rem; color: var(--text-light); margin-bottom: 12px; }
.card .meta { font-size: 0.8rem; color: var(--primary); font-weight: 600; }

/* ===== 面包屑 ===== */
.breadcrumb {
  font-size: 0.85rem;
  color: var(--text-light);
  padding: 16px 0 0;
}
.breadcrumb a { color: var(--text-light); }
.breadcrumb a:hover { color: var(--primary); }
.breadcrumb ol { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; }
.breadcrumb li + li::before { content: "›"; margin-right: 6px; color: var(--border); }

/* ===== 布局：侧栏 + 内容 ===== */
.layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 32px;
  padding: 24px 20px 56px;
  max-width: 1120px;
  margin: 0 auto;
}
@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; }
  .sidebar { order: 2; }
}

.sidebar h3 {
  font-size: 0.95rem;
  margin: 22px 0 10px;
  padding-left: 10px;
  border-left: 3px solid var(--primary);
}
.sidebar h3:first-child { margin-top: 0; }
.sidebar ul { list-style: none; }
.sidebar li a {
  display: block;
  padding: 6px 10px;
  border-radius: 8px;
  color: var(--text);
  font-size: 0.92rem;
}
.sidebar li a:hover { background: var(--bg-soft); color: var(--primary); }

/* ===== 列表页 ===== */
.list-head { margin-bottom: 20px; }
.list-head h1 { font-size: 1.7rem; margin-bottom: 6px; }
.list-head p { color: var(--text-light); font-size: 0.9rem; }

.page-group {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-bottom: 20px;
}
@media (max-width: 620px) { .page-group { grid-template-columns: 1fr; } }

.pager { display: flex; gap: 8px; margin-top: 8px; }
.pager a, .pager span {
  padding: 7px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.9rem;
  color: var(--text);
}
.pager a:hover { border-color: var(--primary); color: var(--primary); }
.pager .current {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

/* ===== 文章详情 ===== */
.article { max-width: 760px; }
.article h1 { font-size: 1.8rem; line-height: 1.4; margin-bottom: 10px; }
.article-meta {
  font-size: 0.85rem;
  color: var(--text-light);
  padding-bottom: 18px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 24px;
}
.article h2 { font-size: 1.3rem; margin: 32px 0 12px; }
.article h3 { font-size: 1.1rem; margin: 22px 0 8px; }
.article p { margin-bottom: 14px; }
.article ul, .article ol { margin: 0 0 14px 22px; }
.article li { margin-bottom: 6px; }
.article table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0 20px;
  font-size: 0.92rem;
}
.article th, .article td {
  padding: 10px 12px;
  border: 1px solid var(--border);
  text-align: left;
}
.article th { background: var(--bg-soft); }
.article code {
  background: var(--bg-soft);
  padding: 2px 6px;
  border-radius: 5px;
  font-size: 0.88em;
  color: var(--primary-dark);
}
.article pre {
  background: #0f172a;
  color: #e2e8f0;
  padding: 16px;
  border-radius: var(--radius);
  overflow-x: auto;
  margin-bottom: 16px;
  font-size: 0.88rem;
  line-height: 1.6;
}
.article pre code { background: none; color: inherit; padding: 0; }
.article blockquote {
  border-left: 4px solid var(--primary);
  background: var(--bg-soft);
  padding: 12px 16px;
  border-radius: 0 8px 8px 0;
  margin-bottom: 14px;
  color: var(--text-light);
}

/* 文章页脚导航 */
.article-nav {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  font-size: 0.92rem;
}
.article-nav a { max-width: 48%; }

/* ===== 页脚 ===== */
.site-footer { background: var(--bg-soft); border-top: 1px solid var(--border); }
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 32px;
  padding: 44px 0 28px;
}
@media (max-width: 700px) { .footer-grid { grid-template-columns: 1fr; } }
.site-footer h4 { font-size: 1rem; margin-bottom: 12px; }
.site-footer p, .site-footer li { font-size: 0.9rem; color: var(--text-light); }
.site-footer ul { list-style: none; }
.site-footer li { margin-bottom: 6px; }
.copyright {
  text-align: center;
  padding: 16px 0 24px;
  font-size: 0.85rem;
  color: var(--text-light);
  border-top: 1px solid var(--border);
}

/* ===== 404 ===== */
.not-found {
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 60px 20px;
}
.not-found h1 { font-size: 4rem; color: var(--primary); margin-bottom: 8px; }
.not-found p { color: var(--text-light); margin-bottom: 24px; }

/* ===== 语言切换 ===== */
.lang-switch {
  margin-left: 8px;
  padding: 5px 12px;
  border: 1px solid var(--primary);
  border-radius: 8px;
  font-size: 0.88rem;
  color: var(--primary);
  white-space: nowrap;
}
.lang-switch:hover { background: var(--bg-soft); color: var(--primary-dark); }
@media (max-width: 860px) {
  .site-nav .lang-switch { margin: 6px 0 0; display: inline-block; }
}