/* ============================================================
   华体主页 / site.css —— 共享外壳与通用组件
   墨水绿 + 暖砂金 + 米白纸面；橙仅用于切换与导出类主操作
   ============================================================ */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
}

body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd, address { margin: 0; padding: 0; }
ul, ol { list-style: none; }
img, svg, video { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; }
[hidden] { display: none !important; }

:root {
  --ink-900: #0E1F1A;
  --ink-700: #1C3A31;
  --jade-600: #2F6B57;
  --jade-100: #DCE8E1;
  --gold-500: #C8963E;
  --gold-100: #F4E7CE;
  --orange-600: #D2601A;
  --orange-700: #B8500F;
  --slate-500: #6B7A74;
  --paper-050: #FBF8F2;
  --line-200: #D9D4C7;

  --font-display: "Songti SC", "Source Han Serif SC", "Noto Serif CJK SC", "STSong", SimSun, "Times New Roman", serif;
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC", "Microsoft YaHei", -apple-system, "Segoe UI", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Menlo, Consolas, "Courier New", monospace;

  --step--1: 0.75rem;
  --step-0: 0.875rem;
  --step-1: 1rem;
  --step-2: 1.25rem;
  --step-3: 1.5625rem;
  --step-4: 1.9375rem;
  --step-5: 2.5rem;
  --step-6: 3.125rem;
  --step-7: 4rem;
  --numeral: 6rem;

  --gutter: clamp(1rem, 3vw, 2.5rem);
  --radius-sm: 2px;
  --radius: 4px;
  --shadow-1: 0 1px 2px rgba(14, 31, 26, 0.06);
  --shadow-2: 0 2px 6px rgba(14, 31, 26, 0.09);
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --header-h: 76px;
}

/* ---------- 基础排版 ---------- */
body {
  font-family: var(--font-sans);
  font-size: var(--step-1);
  line-height: 1.75;
  color: var(--ink-900);
  background-color: var(--paper-050);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

@media (min-width: 1024px) {
  body { font-size: 1.0625rem; }
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.28;
  color: var(--ink-900);
}

strong { font-weight: 600; }
small { font-size: var(--step--1); }

a:focus-visible,
button:focus-visible,
summary:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--gold-500);
  outline-offset: 4px;
  border-radius: var(--radius-sm);
}

::selection { background: var(--gold-100); color: var(--ink-900); }

/* ---------- 跳过链接 ---------- */
.skip-link {
  position: absolute;
  left: var(--gutter);
  top: -4rem;
  z-index: 300;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0.65rem 1.1rem;
  background: var(--ink-900);
  color: var(--paper-050);
  border-radius: var(--radius);
  font-size: var(--step-0);
  letter-spacing: 0.02em;
  transition: top 0.18s var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible { top: 0.75rem; }

/* ============================================================
   页头
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  background-color: rgba(251, 248, 242, 0.97);
  border-bottom: 1px solid transparent;
  transition: background-color 0.2s var(--ease), border-color 0.2s var(--ease),
              box-shadow 0.2s var(--ease);
}
.site-header.is-condensed {
  background-color: var(--paper-050);
  border-bottom-color: var(--line-200);
  box-shadow: 0 1px 0 rgba(14, 31, 26, 0.03);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0.75rem var(--gutter);
  min-height: var(--header-h);
  transition: min-height 0.2s var(--ease);
}
.site-header.is-condensed .header-inner { min-height: 62px; }

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  min-height: 44px;
  flex: 0 0 auto;
}
.brand-mark {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 1.3125rem;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--ink-900);
}
.brand-rule {
  width: 1px;
  height: 20px;
  background-color: var(--gold-500);
  flex: 0 0 auto;
}
.brand-sub {
  font-size: var(--step--1);
  letter-spacing: 0.06em;
  color: var(--slate-500);
  white-space: nowrap;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-left: auto;
}

.primary-nav { display: block; }

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}
.nav-item { display: flex; align-items: center; }

.nav-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 0.75rem;
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: var(--step-0);
  letter-spacing: -0.01em;
  color: var(--ink-700);
  border-radius: var(--radius-sm);
  transition: color 0.18s var(--ease);
}
.nav-link::after {
  content: "";
  position: absolute;
  left: 0.75rem;
  right: 0.75rem;
  bottom: 0.5rem;
  height: 2px;
  background-color: var(--gold-500);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform 0.18s var(--ease);
}
.nav-link:hover { color: var(--ink-900); }
.nav-link:hover::after { transform: scaleX(1); }
.nav-link[aria-current="page"] { color: var(--ink-900); }
.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
  background-color: var(--orange-600);
}

.header-cta {
  flex: 0 0 auto;
  font-size: 0.8125rem;
  padding: 0.5rem 0.9rem;
}

.nav-toggle {
  display: none;
  position: relative;
  width: 44px;
  height: 44px;
  flex: 0 0 auto;
  padding: 0;
  background-color: transparent;
  border: 1px solid var(--line-200);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: border-color 0.18s var(--ease), background-color 0.18s var(--ease);
}
.nav-toggle:hover { border-color: var(--gold-500); }
.nav-toggle-lines,
.nav-toggle-lines::before,
.nav-toggle-lines::after {
  position: absolute;
  width: 18px;
  height: 2px;
  background-color: var(--ink-900);
  transition: transform 0.2s var(--ease), opacity 0.2s var(--ease),
              background-color 0.2s var(--ease);
}
.nav-toggle-lines {
  top: 50%;
  left: 50%;
  margin-top: -1px;
  transform: translateX(-50%);
}
.nav-toggle-lines::before,
.nav-toggle-lines::after {
  content: "";
  left: 0;
}
.nav-toggle-lines::before { top: -6px; }
.nav-toggle-lines::after { top: 6px; }

.nav-toggle[aria-expanded="true"] .nav-toggle-lines { background-color: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle-lines::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-lines::after { transform: translateY(-6px) rotate(-45deg); }

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background-image: linear-gradient(90deg, var(--gold-500), var(--orange-600));
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform 0.1s linear;
  pointer-events: none;
}

/* 平板：导航字距收紧，避免换行 */
@media (max-width: 1023px) {
  .nav-link { padding: 0 0.55rem; font-size: 0.8125rem; }
  .nav-link::after { left: 0.55rem; right: 0.55rem; }
  .header-cta { font-size: var(--step--1); padding: 0.45rem 0.75rem; }
}

/* 移动端：导航折叠为可横向滑动的胶囊索引 */
@media (max-width: 899px) {
  .nav-toggle { display: inline-flex; align-items: center; justify-content: center; }

  .primary-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    padding: 0.85rem var(--gutter) 1rem;
    background-color: var(--paper-050);
    border-top: 1px solid var(--line-200);
    border-bottom: 1px solid var(--line-200);
    box-shadow: var(--shadow-2);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity 0.18s var(--ease), transform 0.18s var(--ease),
                visibility 0.18s var(--ease);
  }
  .primary-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .nav-list {
    display: flex;
    flex-wrap: nowrap;
    gap: 0.5rem;
    overflow-x: auto;
    padding-bottom: 0.25rem;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: thin;
  }
  .nav-link {
    white-space: nowrap;
    min-height: 44px;
    padding: 0 1rem;
    font-size: 0.8125rem;
    border: 1px solid var(--line-200);
    border-radius: 999px;
    color: var(--ink-700);
  }
  .nav-link::after { display: none; }
  .nav-link:hover { border-color: var(--gold-500); color: var(--ink-900); }
  .nav-link[aria-current="page"] {
    background-color: var(--ink-900);
    border-color: var(--ink-900);
    color: var(--paper-050);
  }
}

@media (max-width: 430px) {
  :root { --header-h: 66px; }
  .brand-sub, .brand-rule { display: none; }
  .header-right { gap: 0.5rem; }
  .header-cta { padding: 0.4rem 0.6rem; font-size: 0.75rem; }
}

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  margin-top: clamp(3rem, 7vw, 6rem);
  background-color: var(--ink-900);
  color: var(--paper-050);
}
.footer-inner {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: clamp(2.5rem, 5vw, 4rem) var(--gutter) 1.5rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem 1.5rem;
}

.footer-brand-mark {
  display: inline-block;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 1.5rem;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--paper-050);
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--gold-500);
}
.footer-tagline {
  margin-top: 1rem;
  max-width: 26ch;
  font-size: var(--step-0);
  line-height: 1.85;
  color: rgba(251, 248, 242, 0.72);
}

.footer-col-title {
  margin-bottom: 0.85rem;
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: var(--step--1);
  letter-spacing: 0.16em;
  color: var(--gold-500);
}

.footer-list { display: flex; flex-direction: column; gap: 0.1rem; }

.footer-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: var(--step-0);
  color: rgba(251, 248, 242, 0.78);
  transition: color 0.18s var(--ease);
}
.footer-link:hover { color: var(--gold-500); }

.footer-contact {
  font-style: normal;
  font-size: var(--step-0);
  line-height: 1.9;
  color: rgba(251, 248, 242, 0.78);
}
.footer-contact span { display: block; }

.footer-contact-note {
  margin-top: 0.75rem;
  font-size: var(--step--1);
  line-height: 1.8;
  color: rgba(251, 248, 242, 0.5);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem 1.25rem;
  margin-top: clamp(1.75rem, 4vw, 2.75rem);
  padding-top: 1rem;
  border-top: 1px solid rgba(217, 212, 199, 0.18);
  font-size: var(--step--1);
  color: rgba(251, 248, 242, 0.6);
}
.footer-copy { display: inline-flex; align-items: center; min-height: 44px; }
.footer-legal-links { display: flex; flex-wrap: wrap; gap: 0.25rem 1.25rem; }
.footer-legal-links a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  color: rgba(251, 248, 242, 0.72);
  transition: color 0.18s var(--ease);
}
.footer-legal-links a:hover { color: var(--gold-500); }

.icp {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--step--1);
  letter-spacing: 0;
  color: rgba(251, 248, 242, 0.55);
}

@media (min-width: 640px) {
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 1000px) {
  .footer-grid {
    grid-template-columns: 1.7fr 1fr 1fr 1.25fr;
    gap: 2.5rem;
  }
  .footer-legal { flex-wrap: nowrap; }
}
@media (max-width: 639px) {
  .icp { margin-left: 0; }
}

/* ============================================================
   布局容器与网格
   ============================================================ */
.container {
  width: 100%;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.container--narrow { max-width: 720px; }

.section { padding-block: clamp(2.5rem, 6vw, 5rem); }

.rule {
  height: 1px;
  border: 0;
  margin: 0;
  background-color: var(--line-200);
}

.grid { display: grid; gap: clamp(1rem, 2.5vw, 1.75rem); }
.grid-2 { grid-template-columns: 1fr; }
.grid-3 { grid-template-columns: 1fr; }

@media (min-width: 768px) {
  .grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 1080px) {
  .grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

/* ============================================================
   文本组件
   ============================================================ */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: var(--step--1);
  letter-spacing: 0.16em;
  color: var(--jade-600);
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background-color: var(--gold-500);
  flex: 0 0 auto;
}

.section-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  letter-spacing: -0.02em;
  line-height: 1.25;
  color: var(--ink-900);
  text-wrap: balance;
}

.numeral {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(2.75rem, 9vw, var(--numeral));
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--gold-500);
}

.lede {
  max-width: 60ch;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--ink-700);
}

.meta-mono {
  font-family: var(--font-mono);
  font-size: var(--step--1);
  letter-spacing: 0;
  color: var(--slate-500);
}

.prose { max-width: 720px; }
.prose p + p { margin-top: 1em; }
.prose h2, .prose h3 { margin-top: 1.75em; margin-bottom: 0.5em; }
.prose ul, .prose ol { margin-top: 0.75em; padding-left: 1.25em; }
.prose ul { list-style: square; }
.prose ol { list-style: decimal; }
.prose li + li { margin-top: 0.35em; }
.prose a {
  color: var(--jade-600);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}
.prose a:hover { color: var(--ink-900); }

/* ============================================================
   按钮
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-height: 44px;
  padding: 0.65rem 1.15rem;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: var(--step-0);
  letter-spacing: -0.01em;
  line-height: 1.2;
  cursor: pointer;
  transition: background-color 0.18s var(--ease), color 0.18s var(--ease),
              border-color 0.18s var(--ease);
}

.btn-primary {
  background-color: var(--orange-600);
  border-color: var(--orange-600);
  color: var(--paper-050);
}
.btn-primary:hover { background-color: var(--orange-700); border-color: var(--orange-700); }

.btn-outline-accent {
  background-color: transparent;
  border-color: var(--orange-600);
  color: var(--orange-600);
}
.btn-outline-accent:hover { background-color: var(--orange-600); color: var(--paper-050); }

.btn-solid-ink {
  background-color: var(--ink-900);
  border-color: var(--ink-900);
  color: var(--paper-050);
}
.btn-solid-ink:hover { background-color: var(--ink-700); border-color: var(--ink-700); }

.btn-ghost {
  background-color: transparent;
  border-color: var(--line-200);
  color: var(--ink-900);
}
.btn-ghost:hover { border-color: var(--ink-900); }

/* ============================================================
   卡片、面板、标签、提示
   ============================================================ */
.card {
  padding: clamp(1.25rem, 2.5vw, 1.75rem);
  background-color: #FFFFFF;
  border: 1px solid var(--line-200);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
}
.card--ink {
  background-color: var(--ink-900);
  border-color: var(--ink-700);
  color: var(--paper-050);
}
.card--ink h2, .card--ink h3 { color: var(--paper-050); }
.card--sand { background-color: var(--gold-100); border-color: #E4D2AC; }
.card--jade { background-color: var(--jade-100); border-color: #C6D8CD; }

.panel {
  padding: clamp(1.25rem, 3vw, 2rem);
  background-color: var(--jade-100);
  border: 1px solid #C6D8CD;
  border-radius: var(--radius);
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 26px;
  padding: 0.1rem 0.6rem;
  border: 1px solid var(--line-200);
  border-radius: 999px;
  background-color: var(--paper-050);
  font-size: var(--step--1);
  letter-spacing: 0.02em;
  color: var(--jade-600);
  white-space: nowrap;
}
.tag--gold {
  background-color: var(--gold-100);
  border-color: #E4D2AC;
  color: #8A5F16;
}

.note {
  padding: 1rem 1.25rem;
  background-color: var(--gold-100);
  border-left: 2px solid var(--gold-500);
  border-radius: 0 var(--radius) var(--radius) 0;
  font-size: var(--step-0);
  line-height: 1.8;
  color: var(--ink-700);
}

/* ============================================================
   面包屑
   ============================================================ */
.breadcrumbs {
  margin-bottom: 1.5rem;
  font-size: 0.8125rem;
  color: var(--slate-500);
}
.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
}
.breadcrumb-list li { display: inline-flex; align-items: center; }
.breadcrumb-list li + li::before {
  content: "/";
  margin-right: 0.4rem;
  color: var(--slate-500);
}
.breadcrumbs a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  color: var(--jade-600);
}
.breadcrumbs a:hover { color: var(--ink-900); }
.breadcrumb-list [aria-current="page"] { color: var(--ink-900); }

/* ============================================================
   图片容器（页面阶段放置 img）
   ============================================================ */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  isolation: isolate;
  background-color: var(--jade-100);
  border: 1px solid var(--line-200);
  border-radius: var(--radius);
}
.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  opacity: 0.5;
  mix-blend-mode: multiply;
  background-image: radial-gradient(rgba(14, 31, 26, 0.1) 0.5px, transparent 0.5px);
  background-size: 3px 3px;
}
.media-frame[data-ratio="16-9"] { aspect-ratio: 16 / 9; }
.media-frame[data-ratio="4-3"] { aspect-ratio: 4 / 3; }
.media-frame[data-ratio="1-1"] { aspect-ratio: 1 / 1; }
.media-frame[data-ratio="3-4"] { aspect-ratio: 3 / 4; }
.media-frame[data-ratio="21-9"] { aspect-ratio: 21 / 9; }

/* ============================================================
   主题筛选（只筛当前页面已有内容）
   ============================================================ */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
}
.filter-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0.5rem 1rem;
  border: 1px solid var(--line-200);
  border-radius: 999px;
  background-color: transparent;
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--ink-700);
  cursor: pointer;
  transition: background-color 0.18s var(--ease), color 0.18s var(--ease),
              border-color 0.18s var(--ease);
}
.filter-btn:hover { border-color: var(--gold-500); color: var(--ink-900); }
.filter-btn[aria-pressed="true"] {
  background-color: var(--orange-600);
  border-color: var(--orange-600);
  color: var(--paper-050);
}
.filter-count {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--step--1);
  letter-spacing: 0;
  color: var(--slate-500);
}

@media (max-width: 639px) {
  .filter-count { margin-left: 0; flex-basis: 100%; }
}

/* ============================================================
   进入显现
   ============================================================ */
.has-js [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.5s var(--ease), transform 0.5s var(--ease);
  transition-delay: var(--reveal-delay, 0ms);
  will-change: opacity, transform;
}
.has-js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
  will-change: auto;
}

/* ============================================================
   减少动效
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; scroll-padding-top: 80px; }

  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  .has-js [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .scroll-progress { transition: none; }
  .primary-nav { transition: none; }
}