@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;500;600;700&display=swap');

/* ==============================
   CSS 自定义属性
============================== */
:root {
  --c-primary: #6514ff;
  --c-accent: #bf00ff;
  --c-ground: #1c1726;
  --c-ground-2: #251e33;
  --c-ground-3: #2e2541;
  --c-text: #f0ebff;
  --c-text-muted: #a898cc;
  --c-border: rgba(101, 20, 255, 0.35);
  --c-white: #ffffff;
  --c-neon-glow: rgba(191, 0, 255, 0.4);

  --font-main: 'Space Grotesk', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;

  --radius-card: 18px;
  --radius-sm: 8px;

  --header-h: 72px;
  --section-gap: 80px;
  --container-max: 1200px;
  --content-max: 820px;

  --trans-fast: 200ms ease;
  --trans-std: 280ms ease;
}

/* ==============================
   重置 & 基础
============================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 17px;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--c-ground);
  color: var(--c-text);
  font-family: var(--font-main);
  line-height: 1.65;
  overflow-x: hidden;
}

a {
  color: var(--c-accent);
  text-decoration: none;
  transition: color var(--trans-fast);
}
a:hover, a:focus-visible {
  color: var(--c-white);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

ol, ul {
  list-style: none;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
}

:focus-visible {
  outline: 2px solid var(--c-accent);
  outline-offset: 3px;
}

/* ==============================
   滚动条
============================== */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--c-ground); }
::-webkit-scrollbar-thumb { background: var(--c-primary); border-radius: 3px; }

/* ==============================
   HEADER
============================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 900;
  background: rgba(28, 23, 38, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--c-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  padding: 0 24px;
  max-width: var(--container-max);
  margin: 0 auto;
}

.burger-btn {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 10px 8px;
  min-height: 44px;
  min-width: 44px;
  justify-content: center;
  align-items: center;
  z-index: 1001;
  flex-shrink: 0;
}

.burger-bar {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--c-text);
  border-radius: 2px;
  transition: transform var(--trans-std), opacity var(--trans-std), background var(--trans-fast);
}

.burger-btn.is-open .burger-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.burger-btn.is-open .burger-bar:nth-child(2) {
  opacity: 0;
}
.burger-btn.is-open .burger-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.brand-center {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--c-white);
  letter-spacing: 0.03em;
  text-transform: uppercase;
  white-space: nowrap;
  padding: 8px 0;
}
.brand-center:hover {
  color: var(--c-accent);
}

.header-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 8px 20px;
  background: var(--c-primary);
  color: var(--c-white);
  font-weight: 700;
  font-size: 0.9rem;
  border-radius: var(--radius-sm);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  transition: background var(--trans-fast), transform var(--trans-fast);
  flex-shrink: 0;
}
.header-cta:hover {
  background: var(--c-accent);
  color: var(--c-white);
  transform: translateY(-1px);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  overflow-x: auto;
  padding: 0 24px 0;
  max-width: var(--container-max);
  margin: 0 auto;
  border-top: 1px solid rgba(101, 20, 255, 0.15);
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.site-nav::-webkit-scrollbar { display: none; }

.nav-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 6px 12px;
  color: var(--c-text-muted);
  font-size: 0.82rem;
  font-weight: 500;
  white-space: nowrap;
  letter-spacing: 0.04em;
  border-radius: var(--radius-sm);
  transition: color var(--trans-fast), background var(--trans-fast);
}
.nav-link:hover {
  color: var(--c-white);
  background: rgba(101, 20, 255, 0.2);
}
.nav-link--active {
  color: var(--c-white);
  background: rgba(101, 20, 255, 0.3);
}

/* ==============================
   全屏遮罩菜单
============================== */
.fullscreen-nav {
  position: fixed;
  inset: 0;
  z-index: 950;
  background: var(--c-ground);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--trans-std);
}
.fullscreen-nav.is-open {
  opacity: 1;
  pointer-events: all;
}

.nav-close {
  position: absolute;
  top: 24px;
  right: 24px;
  font-size: 1.8rem;
  color: var(--c-text);
  min-height: 44px;
  min-width: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: color var(--trans-fast), background var(--trans-fast);
}
.nav-close:hover {
  color: var(--c-white);
  background: rgba(101, 20, 255, 0.3);
}

.fullnav-inner {
  display: flex;
  flex-direction: column;
  gap: 8px;
  width: 100%;
  max-width: 600px;
  padding: 0 32px;
}

.fullnav-link {
  display: block;
  padding: 16px 24px;
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--c-text);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-left: 4px solid transparent;
  border-radius: var(--radius-sm);
  transition: color var(--trans-fast), border-color var(--trans-fast), background var(--trans-fast), transform var(--trans-std);
  opacity: 0;
  transform: translateX(-20px);
}
.fullscreen-nav.is-open .fullnav-link {
  opacity: 1;
  transform: translateX(0);
  transition: color var(--trans-fast), border-color var(--trans-fast), background var(--trans-fast),
              opacity var(--trans-std) calc(var(--i, 0) * 40ms),
              transform var(--trans-std) calc(var(--i, 0) * 40ms);
}
.fullnav-link:hover {
  color: var(--c-white);
  border-color: var(--c-accent);
  background: rgba(191, 0, 255, 0.1);
}

/* ==============================
   HERO（首页）
============================== */
.hero-section {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: flex-end;
  justify-content: flex-end;
  padding-top: var(--header-h);
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-pattern {
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(
      0deg,
      transparent,
      transparent 48px,
      rgba(101, 20, 255, 0.08) 48px,
      rgba(101, 20, 255, 0.08) 49px
    ),
    repeating-linear-gradient(
      90deg,
      transparent,
      transparent 48px,
      rgba(101, 20, 255, 0.08) 48px,
      rgba(101, 20, 255, 0.08) 49px
    );
  animation: patternDrift 12s linear infinite;
}

@keyframes patternDrift {
  0% { background-position: 0 0, 0 0; }
  100% { background-position: 48px 48px, 48px 48px; }
}

.hero-gradient {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 60% 70% at 80% 50%, rgba(101, 20, 255, 0.4) 0%, transparent 65%),
              radial-gradient(ellipse 40% 50% at 90% 80%, rgba(191, 0, 255, 0.3) 0%, transparent 60%),
              linear-gradient(180deg, rgba(28, 23, 38, 0.3) 0%, rgba(28, 23, 38, 0.85) 100%);
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: right;
  padding: 80px 48px 100px;
  max-width: 760px;
}

.hero-badge {
  display: inline-block;
  background: var(--c-primary);
  color: var(--c-white);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  padding: 6px 14px;
  border-radius: 4px;
  margin-bottom: 24px;
}

.hero-h1 {
  font-size: clamp(2.2rem, 5vw, 4rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.01em;
  text-transform: uppercase;
  color: var(--c-white);
  margin-bottom: 20px;
}

.hero-sub {
  font-size: 1.1rem;
  color: var(--c-text-muted);
  margin-bottom: 36px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: flex-end;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  min-height: 52px;
  padding: 14px 32px;
  background: var(--c-primary);
  color: var(--c-white);
  font-weight: 700;
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  border-radius: var(--radius-sm);
  transition: background var(--trans-fast), transform var(--trans-fast), box-shadow var(--trans-fast);
}
.btn-primary:hover {
  background: var(--c-accent);
  color: var(--c-white);
  transform: translateY(-2px);
  box-shadow: 0 8px 30px var(--c-neon-glow);
}

.btn-ghost {
  display: inline-flex;
  align-items: center;
  min-height: 52px;
  padding: 14px 32px;
  border: 2px solid var(--c-primary);
  color: var(--c-text);
  font-weight: 700;
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  border-radius: var(--radius-sm);
  transition: border-color var(--trans-fast), color var(--trans-fast), background var(--trans-fast);
}
.btn-ghost:hover {
  border-color: var(--c-accent);
  color: var(--c-white);
  background: rgba(191, 0, 255, 0.1);
}

.hero-tags {
  position: absolute;
  top: 30%;
  left: 40px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  z-index: 2;
}

.float-tag {
  display: inline-block;
  background: rgba(28, 23, 38, 0.8);
  border: 1px solid var(--c-primary);
  color: var(--c-accent);
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 8px 14px;
  border-radius: 4px;
  backdrop-filter: blur(4px);
}
.ft1 { animation: tagFloat 3s ease-in-out infinite; }
.ft2 { animation: tagFloat 3s ease-in-out infinite 0.6s; }
.ft3 { animation: tagFloat 3s ease-in-out infinite 1.2s; }

@keyframes tagFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-6px); }
}

/* ==============================
   SECTION 通用
============================== */
.section-inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

.eyebrow {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--c-accent);
  margin-bottom: 12px;
  padding: 4px 10px;
  border: 1px solid rgba(191, 0, 255, 0.4);
  border-radius: 4px;
}

.section-h2 {
  font-size: clamp(1.6rem, 3.5vw, 2.4rem);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: -0.01em;
  color: var(--c-white);
  margin-bottom: 48px;
  line-height: 1.2;
}

/* ==============================
   CONTENT AREA
============================== */
.content-area {
  padding: var(--section-gap) 0;
}

.content-wrap {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 24px;
}

.page-content-block {
  font-size: 1rem;
  line-height: 1.75;
  color: var(--c-text);
}

.page-content-block h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--c-white);
  margin: 2.5rem 0 1rem;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.page-content-block h3 {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--c-accent);
  margin: 2rem 0 0.8rem;
}

.page-content-block p {
  margin-bottom: 1.2rem;
}

.page-content-block a {
  color: var(--c-accent);
  text-decoration: underline;
  text-decoration-color: rgba(191, 0, 255, 0.4);
  text-underline-offset: 3px;
}
.page-content-block a:hover {
  color: var(--c-white);
  text-decoration-color: var(--c-white);
}

.page-content-block ul,
.page-content-block ol {
  padding-left: 1.5rem;
  margin-bottom: 1.2rem;
}
.page-content-block ul { list-style: disc; }
.page-content-block ol { list-style: decimal; }
.page-content-block li { margin-bottom: 0.5rem; }

.page-content-block strong { color: var(--c-white); font-weight: 700; }

.page-content-block blockquote {
  border-left: 4px solid var(--c-primary);
  padding: 12px 20px;
  margin: 1.5rem 0;
  background: rgba(101, 20, 255, 0.08);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.page-content-block table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.9rem;
}
.page-content-block th,
.page-content-block td {
  padding: 10px 14px;
  border: 1px solid var(--c-border);
  text-align: left;
}
.page-content-block th {
  background: rgba(101, 20, 255, 0.2);
  color: var(--c-white);
  font-weight: 700;
  text-transform: uppercase;
}
.page-content-block tr:nth-child(even) td {
  background: rgba(255, 255, 255, 0.03);
}

time.article-date {
  font-size: 0.82rem;
  color: var(--c-accent);
}

/* ==============================
   NAV CARDS SECTION（首页）
============================== */
.nav-cards-section {
  padding: var(--section-gap) 0;
  background: var(--c-ground-2);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.card-item {
  display: contents;
}

.card-block {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 32px 28px;
  background: var(--c-ground-3);
  border-radius: var(--radius-card);
  border: 1px solid var(--c-border);
  transition: transform var(--trans-std), border-color var(--trans-std), box-shadow var(--trans-std);
  position: relative;
  overflow: hidden;
}
.card-block::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--card-accent, var(--c-primary));
  border-radius: var(--radius-card) var(--radius-card) 0 0;
}
.card-block:hover {
  transform: translateY(-4px);
  border-color: var(--card-accent, var(--c-primary));
  box-shadow: 0 12px 40px rgba(101, 20, 255, 0.2);
  color: var(--c-white);
}

.card-index {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--card-accent, var(--c-primary));
  text-transform: uppercase;
}

.card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--c-white);
  line-height: 1.3;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.card-desc {
  font-size: 0.85rem;
  color: var(--c-text-muted);
  line-height: 1.55;
  flex-grow: 1;
}

.card-arrow {
  font-size: 1.2rem;
  color: var(--card-accent, var(--c-primary));
  transition: transform var(--trans-fast);
  align-self: flex-end;
}
.card-block:hover .card-arrow {
  transform: translateX(4px);
}

/* ==============================
   RECENT SECTION（首页）
============================== */
.recent-section {
  padding: var(--section-gap) 0;
}

.recent-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.recent-item {
  border-bottom: 1px solid var(--c-border);
}

.recent-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 0;
  color: var(--c-text);
  transition: color var(--trans-fast), padding-left var(--trans-std);
}
.recent-link:hover {
  color: var(--c-white);
  padding-left: 8px;
}

.recent-title {
  font-size: 1rem;
  font-weight: 500;
}

.post-date {
  font-size: 0.78rem;
  color: var(--c-text-muted);
  white-space: nowrap;
  flex-shrink: 0;
}

/* ==============================
   ARTICLE HERO
============================== */
.article-hero {
  padding-top: calc(var(--header-h) + 48px);
  padding-bottom: 48px;
  position: relative;
  background: linear-gradient(135deg, var(--c-ground) 0%, var(--c-ground-2) 100%);
  overflow: hidden;
}
.article-hero::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 50%;
  height: 100%;
  background: radial-gradient(ellipse 80% 100% at 100% 50%, rgba(101, 20, 255, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.article-hero-inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

.article-h1 {
  font-size: clamp(1.8rem, 4vw, 3rem);
  font-weight: 700;
  color: var(--c-white);
  text-transform: uppercase;
  letter-spacing: -0.01em;
  line-height: 1.15;
  margin: 16px 0 20px;
}

.article-hero-deco {
  position: absolute;
  top: 0;
  right: -80px;
  width: 400px;
  height: 100%;
  background: repeating-linear-gradient(
    -45deg,
    transparent,
    transparent 20px,
    rgba(101, 20, 255, 0.04) 20px,
    rgba(101, 20, 255, 0.04) 21px
  );
}

.article-meta {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}

.article-content-area .content-wrap {
  max-width: var(--content-max);
}

/* ==============================
   BREADCRUMB
============================== */
.breadcrumb {
  font-size: 0.8rem;
  color: var(--c-text-muted);
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 4px;
}
.breadcrumb a {
  color: var(--c-text-muted);
}
.breadcrumb a:hover { color: var(--c-accent); }
.breadcrumb span[aria-current] { color: var(--c-text); }

/* ==============================
   CHILDREN LIST（article 子页）
============================== */
.children-section {
  padding: var(--section-gap) 0;
  background: var(--c-ground-2);
}

.children-ol {
  display: flex;
  flex-direction: column;
  gap: 12px;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

.child-li {
  border-left: 3px solid var(--c-primary);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.child-link {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  padding: 20px 24px;
  background: var(--c-ground-3);
  color: var(--c-text);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  transition: background var(--trans-fast), color var(--trans-fast);
}
.child-link:hover {
  background: rgba(101, 20, 255, 0.15);
  color: var(--c-white);
}

.child-num {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--c-primary);
  flex-shrink: 0;
  padding-top: 3px;
}

.child-info {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.child-info strong {
  font-size: 1rem;
  font-weight: 700;
  color: var(--c-white);
}
.child-info small {
  font-size: 0.85rem;
  color: var(--c-text-muted);
}

/* ==============================
   SIBLINGS ASIDE
============================== */
.siblings-aside {
  padding: var(--section-gap) 0;
  max-width: var(--container-max);
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}

.siblings-h2 {
  margin-bottom: 24px;
}

.siblings-ol {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}

.siblings-ol li {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.siblings-ol a {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--c-text);
  padding: 14px 18px 0;
  border-top: 2px solid var(--c-border);
  transition: color var(--trans-fast), border-color var(--trans-fast);
}
.siblings-ol a:hover {
  color: var(--c-accent);
  border-color: var(--c-accent);
}

.siblings-ol small {
  font-size: 0.82rem;
  color: var(--c-text-muted);
  padding: 0 18px 14px;
}

/* ==============================
   BACK TO TOP
============================== */
.back-to-top-wrap {
  text-align: center;
  padding: 40px 0;
}

.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border: 1px solid var(--c-border);
  border-radius: var(--radius-sm);
  color: var(--c-text-muted);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  transition: border-color var(--trans-fast), color var(--trans-fast), background var(--trans-fast);
}
.back-btn:hover {
  border-color: var(--c-primary);
  color: var(--c-white);
  background: rgba(101, 20, 255, 0.1);
}

/* ==============================
   ABOUT PAGE
============================== */
.about-hero {
  padding-top: calc(var(--header-h) + 60px);
  padding-bottom: 80px;
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--c-ground) 0%, var(--c-ground-3) 100%);
}

.about-hero-inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 2;
}

.about-h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  color: var(--c-white);
  text-transform: uppercase;
  letter-spacing: -0.01em;
  line-height: 1.1;
  margin: 16px 0 20px;
}

.about-sub {
  font-size: 1.1rem;
  color: var(--c-text-muted);
  max-width: 600px;
  line-height: 1.7;
}

.about-hero-deco {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.deco-block {
  position: absolute;
  border-radius: var(--radius-card);
  opacity: 0.1;
}
.db1 {
  width: 200px;
  height: 200px;
  background: var(--c-primary);
  right: 10%;
  top: 20%;
  transform: rotate(15deg);
  animation: decoSpin 20s linear infinite;
}
.db2 {
  width: 120px;
  height: 120px;
  background: var(--c-accent);
  right: 20%;
  top: 50%;
  transform: rotate(-10deg);
  animation: decoSpin 15s linear infinite reverse;
}
.db3 {
  width: 80px;
  height: 80px;
  background: var(--c-primary);
  right: 5%;
  top: 60%;
  animation: decoSpin 25s linear infinite;
}

@keyframes decoSpin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.about-content-area .content-wrap {
  max-width: var(--content-max);
}

.about-links-block {
  padding: var(--section-gap) 0;
  background: var(--c-ground-2);
}

.about-nav-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.about-nav-link {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 20px 24px;
  background: var(--c-ground-3);
  border-radius: var(--radius-card);
  color: var(--c-text);
  border: 1px solid var(--c-border);
  transition: background var(--trans-fast), border-color var(--trans-fast), transform var(--trans-std);
}
.about-nav-link:hover {
  background: rgba(101, 20, 255, 0.15);
  border-color: var(--c-primary);
  color: var(--c-white);
  transform: translateX(6px);
}

.about-nav-num {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--c-primary);
  flex-shrink: 0;
  min-width: 28px;
}

.about-nav-info {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.about-nav-info strong {
  font-size: 1rem;
  font-weight: 700;
  color: var(--c-white);
}
.about-nav-info small {
  font-size: 0.82rem;
  color: var(--c-text-muted);
}

/* ==============================
   PRIVACY PAGE
============================== */
.privacy-header {
  padding-top: calc(var(--header-h) + 48px);
  padding-bottom: 48px;
  background: var(--c-ground-2);
  border-bottom: 1px solid var(--c-border);
}

.privacy-header-inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

.privacy-h1 {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 700;
  color: var(--c-white);
  text-transform: uppercase;
  letter-spacing: -0.01em;
  line-height: 1.15;
  margin: 12px 0 16px;
}

.privacy-updated {
  font-size: 0.82rem;
  color: var(--c-text-muted);
}
.privacy-updated time { color: var(--c-accent); }

.privacy-content-area .content-wrap {
  max-width: var(--content-max);
}
.privacy-content-wrap {
  padding-top: 60px;
  padding-bottom: 60px;
}

.privacy-footer-links {
  display: flex;
  gap: 24px;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--c-border);
  flex-wrap: wrap;
}
.privacy-footer-links a {
  color: var(--c-text-muted);
  font-size: 0.9rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.privacy-footer-links a:hover { color: var(--c-accent); }

/* ==============================
   FOOTER
============================== */
.site-footer {
  background: var(--c-ground-3);
  border-top: 1px solid var(--c-border);
  margin-top: 0;
}

.footer-brand-block {
  padding: 60px 24px 40px;
  text-align: center;
  border-bottom: 1px solid var(--c-border);
  overflow: hidden;
}

.footer-brand-text {
  font-size: clamp(2.5rem, 8vw, 6rem);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--c-primary) 0%, var(--c-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  display: block;
  line-height: 1.1;
}

.footer-cols {
  display: flex;
  gap: 0;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 48px 24px;
  border-bottom: 1px solid var(--c-border);
}

.footer-dl {
  flex: 1;
  padding: 0 24px;
  border-right: 1px solid var(--c-border);
}
.footer-dl:first-child { padding-left: 0; }
.footer-dl:last-child {
  border-right: none;
  padding-right: 0;
}

.footer-dl dt {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--c-accent);
  margin-bottom: 16px;
}

.footer-dl dd {
  margin-bottom: 10px;
}

.footer-dl dd a {
  font-size: 0.88rem;
  color: var(--c-text-muted);
  transition: color var(--trans-fast);
}
.footer-dl dd a:hover { color: var(--c-white); }

.footer-bottom {
  text-align: center;
  padding: 24px;
}

.footer-copy {
  font-size: 0.78rem;
  color: var(--c-text-muted);
  line-height: 1.6;
}

/* ==============================
   prefers-reduced-motion
============================== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* ==============================
   RESPONSIVE — 平板 768px 以下
============================== */
@media (max-width: 900px) {
  :root {
    --section-gap: 56px;
  }

  .card-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .footer-cols {
    flex-wrap: wrap;
    gap: 32px;
  }
  .footer-dl {
    flex: 1 1 calc(50% - 32px);
    border-right: none;
    padding: 0;
  }
}

/* ==============================
   RESPONSIVE — 手机 768px 以下
============================== */
@media (max-width: 768px) {
  :root {
    --header-h: 64px;
    --section-gap: 48px;
  }

  html { font-size: 16px; }

  .site-nav {
    padding: 0 16px;
    gap: 2px;
  }
  .nav-link {
    padding: 6px 10px;
    font-size: 0.76rem;
  }

  .header-inner {
    padding: 0 16px;
  }

  .brand-center {
    font-size: 0.9rem;
  }

  .hero-content {
    padding: 60px 24px 80px;
    text-align: right;
  }

  .hero-tags {
    display: none;
  }

  .hero-actions {
    justify-content: flex-end;
  }

  .btn-primary, .btn-ghost {
    min-height: 48px;
    padding: 12px 24px;
    font-size: 0.9rem;
  }

  .card-grid {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .article-hero {
    padding-top: calc(var(--header-h) + 32px);
    padding-bottom: 36px;
  }

  .article-h1 {
    font-size: 1.6rem;
  }

  .footer-cols {
    flex-direction: column;
    gap: 24px;
    padding: 36px 24px;
  }
  .footer-dl {
    flex: none;
    width: 100%;
    padding: 0;
    border: none;
  }

  .siblings-ol {
    grid-template-columns: 1fr;
  }

  .fullnav-link {
    font-size: 1.1rem;
    padding: 14px 20px;
  }

  .footer-brand-text {
    font-size: clamp(2rem, 12vw, 3.5rem);
  }

  .section-inner {
    padding: 0 16px;
  }

  .content-wrap {
    padding: 0 16px;
  }

  .children-ol {
    padding: 0 16px;
  }

  .siblings-aside {
    padding-left: 16px;
    padding-right: 16px;
  }
}

/* ==============================
   RESPONSIVE — 极小屏 375px
============================== */
@media (max-width: 400px) {
  .hero-content {
    padding: 40px 16px 60px;
  }

  .hero-h1 {
    font-size: 1.8rem;
  }

  .hero-actions {
    flex-direction: column;
    align-items: flex-end;
  }

  .btn-primary, .btn-ghost {
    width: 100%;
    justify-content: center;
  }

  .breadcrumb {
    font-size: 0.72rem;
  }
}