/* ============ 全局字体与背景 ============ */
:root {
  --md-default-bg-color: #f8f9fc;
  --md-primary-fg-color: #4f46e5;
  --md-accent-fg-color: #6366f1;
  --md-code-bg-color: #f1f5f9;
}

[data-md-color-scheme="slate"] {
  --md-default-bg-color: #0f172a;
  --md-code-bg-color: #1e293b;
}

body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont,
    "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  letter-spacing: 0.01em;
}

.md-typeset {
  font-size: 0.82rem;
  line-height: 1.75;
}

.md-typeset h1, .md-typeset h2, .md-typeset h3 {
  font-weight: 700;
  letter-spacing: -0.01em;
}

/* ============ Hero 横幅 ============ */
.hero {
  position: relative;
  padding: 4rem 2rem 3.5rem;
  text-align: center;
  background:
    radial-gradient(circle at 20% 20%, rgba(99,102,241,.25), transparent 50%),
    radial-gradient(circle at 80% 0%, rgba(236,72,153,.2), transparent 50%),
    linear-gradient(135deg, #4f46e5 0%, #7c3aed 50%, #db2777 100%);
  color: #fff;
  border-radius: 1rem;
  margin: 1.5rem 0 2.5rem;
  overflow: hidden;
}

.hero h1 {
  color: #fff;
  font-size: 2.2rem;
  font-weight: 800;
  margin: 0 0 0.8rem;
  border: none;
}

.hero p {
  color: rgba(255,255,255,.92);
  font-size: 1.05rem;
  max-width: 680px;
  margin: 0 auto 1.5rem;
}

.hero .hero-badges {
  display: flex;
  gap: .6rem;
  justify-content: center;
  flex-wrap: wrap;
}

.hero .badge {
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  padding: .35rem .9rem;
  background: rgba(255,255,255,.15);
  border: 1px solid rgba(255,255,255,.25);
  border-radius: 999px;
  font-size: .82rem;
  color: #fff;
  backdrop-filter: blur(8px);
}

/* ============ 分类卡片网格 ============ */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0;
}

.card {
  display: flex;
  flex-direction: column;
  padding: 1.1rem 1.2rem;
  background: var(--md-default-bg-color);
  border: 1px solid rgba(15,23,42,.08);
  border-radius: .75rem;
  text-decoration: none !important;
  transition: transform .15s ease, box-shadow .15s ease, border-color .15s ease;
  height: 100%;
}

[data-md-color-scheme="slate"] .card {
  border-color: rgba(255,255,255,.08);
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 25px -10px rgba(79,70,229,.35);
  border-color: var(--md-primary-fg-color);
}

.card .card-icon {
  font-size: 1.5rem;
  margin-bottom: .5rem;
}

.card .card-title {
  font-weight: 700;
  font-size: .95rem;
  color: var(--md-default-fg-color);
  margin-bottom: .3rem;
}

.card .card-desc {
  font-size: .78rem;
  color: var(--md-default-fg-color--light);
  flex-grow: 1;
}

.card .card-meta {
  margin-top: .6rem;
  font-size: .72rem;
  color: var(--md-primary-fg-color);
  font-weight: 600;
}

/* ============ 数字统计 ============ */
.stat-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  margin: 1.5rem 0 2rem;
}

.stat {
  text-align: center;
  padding: 1.1rem .5rem;
  background: var(--md-default-bg-color);
  border: 1px solid rgba(15,23,42,.08);
  border-radius: .75rem;
}

[data-md-color-scheme="slate"] .stat {
  border-color: rgba(255,255,255,.08);
}

.stat .num {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--md-primary-fg-color);
  line-height: 1.1;
}

.stat .label {
  font-size: .78rem;
  color: var(--md-default-fg-color--light);
  margin-top: .25rem;
}

@media (max-width: 720px) {
  .stat-row { grid-template-columns: repeat(2, 1fr); }
  .hero h1 { font-size: 1.6rem; }
}

/* ============ admonition 圆角 ============ */
.md-typeset .admonition {
  border-radius: .5rem;
  box-shadow: 0 2px 8px -4px rgba(0,0,0,.1);
}

/* ============ 表格美化 ============ */
.md-typeset table:not([class]) {
  border-radius: .5rem;
  overflow: hidden;
  box-shadow: 0 2px 8px -4px rgba(0,0,0,.1);
  border: none;
}

.md-typeset table:not([class]) th {
  background: var(--md-primary-fg-color);
  color: #fff;
}

/* ============ 顶部 header 渐变 ============ */
.md-header {
  background: linear-gradient(90deg, #4f46e5, #7c3aed);
}

/* ============ 代码块圆角 ============ */
.md-typeset code, .md-typeset pre {
  border-radius: .4rem;
}

/* ============ 侧边栏导航美化 ============ */
.md-sidebar--primary {
  background: linear-gradient(180deg, #f8f9fc 0%, #eef2ff 100%);
}

[data-md-color-scheme="slate"] .md-sidebar--primary {
  background: linear-gradient(180deg, #0f172a 0%, #1e1b4b 100%);
}

/* 一级分类标题（Java基础 / 并发 等） */
.md-nav--primary > .md-nav__list > .md-nav__item--section > .md-nav__link {
  font-weight: 700;
  font-size: .88rem;
  color: var(--md-primary-fg-color);
  letter-spacing: .02em;
  padding: .55rem .6rem .35rem;
  margin-top: .25rem;
  border-left: 3px solid var(--md-primary-fg-color);
  background: linear-gradient(90deg, rgba(99,102,241,.10), transparent 70%);
}

/* 二级分组标题（基础语法 / 面向对象 等） */
.md-nav--primary .md-nav__item--section > .md-nav__link {
  font-weight: 600;
  font-size: .8rem;
  color: #334155;
  padding: .35rem .5rem .2rem;
  margin-top: .3rem;
}

[data-md-color-scheme="slate"] .md-nav--primary .md-nav__item--section > .md-nav__link {
  color: #cbd5e1;
}

/* 普通导航项紧凑行高，单行省略避免换行 */
.md-nav--primary .md-nav__link {
  font-size: .78rem;
  line-height: 1.4;
  padding: .28rem .5rem;
  border-radius: .3rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 子项缩进 */
.md-nav--primary .md-nav .md-nav__item {
  padding-left: .5rem;
}

/* hover 效果 */
.md-nav--primary .md-nav__link:hover {
  background: rgba(99,102,241,.08);
  color: var(--md-primary-fg-color);
}

/* 当前页高亮 */
.md-nav__link--active {
  font-weight: 600;
  color: var(--md-primary-fg-color) !important;
  background: rgba(99,102,241,.12);
  border-left: 2px solid var(--md-primary-fg-color);
}

/* 可折叠箭头位置微调 */
.md-nav__item .md-nav__link.md-nav__link--active + .md-nav {
  display: block;
}

/* 侧边栏滚动条美化 */
.md-sidebar--primary::-webkit-scrollbar {
  width: 6px;
}
.md-sidebar--primary::-webkit-scrollbar-thumb {
  background: rgba(99,102,241,.3);
  border-radius: 3px;
}