/*
 * HRDNET Design System v2
 * Modern 2025-2026 aesthetic
 * 设计令牌驱动 - 改 :root 即可换全站风格
 */

:root {
  /* === Brand colors (现代渐变蓝紫) === */
  --hrd-primary: #4f46e5;          /* Indigo 600 */
  --hrd-primary-dark: #3730a3;     /* Indigo 800 */
  --hrd-primary-light: #818cf8;    /* Indigo 400 */
  --hrd-primary-50: #eef2ff;
  --hrd-primary-100: #e0e7ff;
  --hrd-accent: #06b6d4;            /* Cyan 500 - 现代感强调色 */
  --hrd-accent-dark: #0891b2;
  --hrd-gradient: linear-gradient(135deg, #4f46e5 0%, #7c3aed 50%, #06b6d4 100%);
  --hrd-gradient-soft: linear-gradient(135deg, #eef2ff 0%, #f0f9ff 100%);

  /* === Neutrals (柔和、不刺眼) === */
  --bg-primary: #ffffff;
  --bg-secondary: #fafbff;        /* 略带冷调 */
  --bg-tertiary: #f1f5f9;
  --bg-elevated: #ffffff;
  --bg-dark: #0a0a1a;              /* 深蓝黑,更"数字" */
  --bg-dark-soft: #1a1a2e;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-tertiary: #94a3b8;
  --text-inverse: #ffffff;
  --border-color: #e2e8f0;
  --border-soft: #f1f5f9;
  --border-dark: #1e293b;

  /* === Spacing (大量留白) === */
  --space-1: 0.25rem; --space-2: 0.5rem; --space-3: 0.75rem;
  --space-4: 1rem; --space-5: 1.25rem; --space-6: 1.5rem;
  --space-8: 2rem; --space-10: 2.5rem; --space-12: 3rem;
  --space-16: 4rem; --space-20: 5rem; --space-24: 6rem;
  --space-32: 8rem;

  /* === Typography (现代字体栈) === */
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", Roboto, sans-serif;
  --font-display: "Inter", -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;

  /* === Radii (圆润现代) === */
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-2xl: 32px;
  --radius-full: 9999px;

  /* === Shadows (多层柔和) === */
  --shadow-xs: 0 1px 2px 0 rgba(15, 23, 42, 0.04);
  --shadow-sm: 0 2px 4px -1px rgba(15, 23, 42, 0.06), 0 1px 2px -1px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 4px 12px -2px rgba(15, 23, 42, 0.08), 0 2px 6px -1px rgba(15, 23, 42, 0.04);
  --shadow-lg: 0 12px 24px -4px rgba(15, 23, 42, 0.10), 0 6px 12px -2px rgba(15, 23, 42, 0.06);
  --shadow-xl: 0 24px 48px -8px rgba(15, 23, 42, 0.12), 0 12px 24px -4px rgba(15, 23, 42, 0.06);
  --shadow-2xl: 0 32px 64px -12px rgba(15, 23, 42, 0.16), 0 16px 32px -8px rgba(15, 23, 42, 0.08);
  --shadow-glow: 0 0 0 1px rgba(79, 70, 229, 0.10), 0 8px 24px -4px rgba(79, 70, 229, 0.20);
  --shadow-glow-accent: 0 0 0 1px rgba(6, 182, 212, 0.10), 0 8px 24px -4px rgba(6, 182, 212, 0.20);

  /* === Motion (丝滑过渡) === */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --transition: 0.3s var(--ease-out);
  --transition-slow: 0.5s var(--ease-out);

  /* === Container === */
  --container-max: 1200px;
  --container-narrow: 800px;
  --container-padding: var(--space-6);
}

/* === Reset === */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  color: var(--text-primary);
  background: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  font-feature-settings: "cv11", "ss01", "ss03";
}
img, video, svg { max-width: 100%; height: auto; display: block; }
a { color: var(--hrd-primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--hrd-primary-dark); }
button { font-family: inherit; cursor: pointer; border: none; background: none; }

/* === Typography === */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: var(--space-4);
}
h1 { font-size: clamp(2.25rem, 5vw, 3.5rem); letter-spacing: -0.03em; }
h2 { font-size: clamp(1.75rem, 4vw, 2.5rem); letter-spacing: -0.025em; }
h3 { font-size: clamp(1.25rem, 3vw, 1.75rem); }
h4 { font-size: 1.125rem; font-weight: 700; }
p { margin-bottom: var(--space-4); }
ul, ol { margin-bottom: var(--space-4); padding-left: var(--space-6); }
li { margin-bottom: var(--space-2); }
code { background: var(--bg-tertiary); padding: 2px 6px; border-radius: var(--radius-sm); font-family: var(--font-mono); font-size: 0.9em; }
pre { background: var(--bg-dark); color: var(--text-inverse); padding: var(--space-4); border-radius: var(--radius-md); overflow-x: auto; margin: var(--space-4) 0; }
blockquote {
  border-left: 4px solid var(--hrd-primary);
  padding: var(--space-4) var(--space-6);
  background: var(--hrd-primary-50);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin: var(--space-6) 0;
  font-style: italic;
}

/* === Layout === */
.container { max-width: var(--container-max); margin: 0 auto; padding: 0 var(--container-padding); }
.container-narrow { max-width: var(--container-narrow); margin: 0 auto; padding: 0 var(--container-padding); }
.section { padding: var(--space-24) 0; }
.section-sm { padding: var(--space-12) 0; }
.section-lg { padding: var(--space-32) 0; }
.grid { display: grid; gap: var(--space-6); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.flex { display: flex; gap: var(--space-4); }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.text-center { text-align: center; }

/* === Buttons (现代微动效) === */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 0.875rem 1.75rem;
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: -0.01em;
  border-radius: var(--radius-full);
  transition: all var(--transition);
  cursor: pointer;
  text-decoration: none;
  border: 1.5px solid transparent;
  white-space: nowrap;
  position: relative;
  overflow: hidden;
}
.btn-primary {
  background: var(--hrd-gradient);
  color: var(--text-inverse);
  box-shadow: var(--shadow-glow);
}
.btn-primary::before {
  content: "";
  position: absolute; inset: 0;
  background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #22d3ee 100%);
  opacity: 0;
  transition: opacity var(--transition);
}
.btn-primary > * { position: relative; z-index: 1; }
.btn-primary:hover::before { opacity: 1; }
.btn-primary:hover { color: var(--text-inverse); transform: translateY(-2px); box-shadow: 0 12px 28px -4px rgba(79, 70, 229, 0.30); }

.btn-accent {
  background: var(--hrd-accent);
  color: #ffffff;
  box-shadow: var(--shadow-glow-accent);
}
.btn-accent:hover { background: var(--hrd-accent-dark); color: #fff; transform: translateY(-2px); }

.btn-outline {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-inverse);
  border-color: rgba(255, 255, 255, 0.25);
  backdrop-filter: blur(8px);
}
.btn-outline:hover { background: rgba(255, 255, 255, 0.15); color: var(--text-inverse); border-color: rgba(255, 255, 255, 0.4); }

.btn-ghost {
  background: transparent;
  color: var(--hrd-primary);
  border-color: var(--border-color);
}
.btn-ghost:hover { background: var(--hrd-primary-50); border-color: var(--hrd-primary); }

.btn-sm { padding: 0.5rem 1.25rem; font-size: 0.875rem; }
.btn-lg { padding: 1.125rem 2.5rem; font-size: 1.05rem; }

/* === Header (玻璃态 sticky) === */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--border-soft);
  transition: all var(--transition);
}
.site-header.scrolled {
  background: rgba(255, 255, 255, 0.85);
  box-shadow: var(--shadow-sm);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  padding: var(--space-4) 0;
  gap: var(--space-6);
}
.site-branding { display: flex; align-items: center; gap: var(--space-3); text-decoration: none; }
.site-logo {
  display: flex; align-items: center; gap: var(--space-2);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.25rem;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}
.site-logo .logo-mark {
  width: 36px; height: 36px;
  background: var(--hrd-gradient);
  border-radius: var(--radius-md);
  display: flex; align-items: center; justify-content: center;
  color: white; font-size: 1.1rem; font-weight: 800;
  box-shadow: var(--shadow-glow);
}
.site-logo .logo-text { display: flex; flex-direction: column; line-height: 1.1; }
.site-logo strong { font-size: 1.05rem; }
.site-logo small { font-size: 0.7rem; color: var(--text-tertiary); font-weight: 500; letter-spacing: 0.05em; text-transform: uppercase; }
.main-nav { display: flex; gap: var(--space-2); align-items: center; }
.main-nav > a,
.main-nav > .nav-item > .nav-link {
  color: var(--text-primary);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 0.5rem 0.875rem;
  border-radius: var(--radius-md);
  transition: all var(--transition);
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  text-decoration: none;
}
.main-nav > a:not(.btn):hover,
.main-nav > .nav-item:hover > .nav-link,
.main-nav > .nav-item.open > .nav-link {
  background: var(--bg-tertiary);
  color: var(--hrd-primary);
}
.main-nav .caret { transition: transform var(--transition); opacity: 0.5; }
.main-nav .nav-item:hover .caret,
.main-nav .nav-item.open .caret { transform: rotate(180deg); opacity: 1; }

/* === Dropdown (二级菜单 - 现代玻璃态) === */
.nav-item { position: relative; }
.nav-item .dropdown {
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%) translateY(-8px);
  min-width: 640px;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  padding: var(--space-4);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: all 0.25s var(--ease-out);
  z-index: 200;
}
.nav-item .dropdown::before {
  content: "";
  position: absolute;
  top: -4px; left: 50%;
  transform: translateX(-50%) rotate(45deg);
  width: 12px; height: 12px;
  background: rgba(255, 255, 255, 0.95);
  border-top: 1px solid var(--border-color);
  border-left: 1px solid var(--border-color);
  border-radius: 2px 0 0 0;
}
.nav-item:hover .dropdown,
.nav-item.open .dropdown {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}
.dropdown-inner { display: flex; flex-direction: column; gap: var(--space-3); }
.dropdown-overview {
  display: flex; flex-direction: column;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  background: var(--hrd-gradient-soft);
  text-decoration: none;
  color: var(--text-primary);
  transition: all var(--transition);
}
.dropdown-overview strong { font-size: 0.95rem; font-weight: 700; color: var(--hrd-primary); }
.dropdown-overview span { font-size: 0.8rem; color: var(--text-secondary); margin-top: 2px; }
.dropdown-overview:hover { background: var(--hrd-primary-100); }

.dropdown-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-1);
}
.dropdown-item {
  display: flex; flex-direction: column;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  text-decoration: none;
  color: var(--text-primary);
  transition: all var(--transition);
}
.dropdown-item strong { font-size: 0.9rem; font-weight: 600; }
.dropdown-item span { font-size: 0.75rem; color: var(--text-tertiary); margin-top: 2px; line-height: 1.4; }
.dropdown-item:hover {
  background: var(--bg-tertiary);
  color: var(--hrd-primary);
}

.menu-toggle { display: none; }

/* === Hero (现代渐变 + 装饰) === */
.hero {
  position: relative;
  background: var(--bg-dark);
  color: var(--text-inverse);
  padding: var(--space-32) 0 var(--space-24);
  overflow: hidden;
  isolation: isolate;
}
.hero::before {
  content: "";
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 20% 0%, rgba(124, 58, 237, 0.35), transparent 50%),
    radial-gradient(ellipse 60% 80% at 80% 100%, rgba(6, 182, 212, 0.25), transparent 50%),
    radial-gradient(ellipse 100% 100% at 50% 50%, rgba(79, 70, 229, 0.20), transparent 60%);
  z-index: -1;
}
.hero::after {
  content: "";
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 40%, black 30%, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 40%, black 30%, transparent 80%);
  z-index: -1;
}
.hero-inner { max-width: 880px; }
.hero-badge {
  display: inline-flex; align-items: center; gap: var(--space-2);
  padding: 0.5rem 1rem;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(12px);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: var(--space-6);
}
.hero-badge .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: #22c55e;
  box-shadow: 0 0 0 3px rgba(34, 197, 94, 0.25);
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 3px rgba(34, 197, 94, 0.25); }
  50% { box-shadow: 0 0 0 6px rgba(34, 197, 94, 0.1); }
}
.hero h1 {
  color: var(--text-inverse);
  font-size: clamp(2.5rem, 6vw, 4rem);
  margin-bottom: var(--space-6);
  font-weight: 800;
  line-height: 1.1;
}
.hero h1 .gradient {
  background: linear-gradient(135deg, #818cf8 0%, #c084fc 50%, #67e8f9 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  display: inline-block;
}
.hero p {
  font-size: 1.15rem;
  margin-bottom: var(--space-8);
  opacity: 0.85;
  max-width: 640px;
  line-height: 1.7;
}
.hero-cta { display: flex; gap: var(--space-3); flex-wrap: wrap; margin-bottom: var(--space-12); }
.hero-stats {
  display: flex; gap: var(--space-12);
  margin-top: var(--space-8);
  flex-wrap: wrap;
  padding-top: var(--space-8);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}
.hero-stat-num {
  font-size: 2.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, #818cf8, #67e8f9);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  line-height: 1;
  letter-spacing: -0.02em;
}
.hero-stat-label { font-size: 0.85rem; opacity: 0.6; margin-top: var(--space-2); font-weight: 500; }

/* 装饰元素 */
.hero-decoration {
  position: absolute;
  top: 15%; right: -5%;
  width: 500px; height: 500px;
  background: radial-gradient(circle, rgba(124, 58, 237, 0.4) 0%, transparent 70%);
  border-radius: 50%;
  filter: blur(80px);
  z-index: -1;
  pointer-events: none;
}

/* === Card (现代玻璃态) === */
.card {
  position: relative;
  background: var(--bg-elevated);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  transition: all 0.4s var(--ease-out);
  display: block;
  color: var(--text-primary);
  overflow: hidden;
}
.card::before {
  content: "";
  position: absolute; inset: 0;
  background: var(--hrd-gradient-soft);
  opacity: 0;
  transition: opacity var(--transition);
  pointer-events: none;
}
.card > * { position: relative; z-index: 1; }
.card:hover {
  border-color: rgba(79, 70, 229, 0.2);
  box-shadow: var(--shadow-xl);
  transform: translateY(-4px);
}
.card:hover::before { opacity: 0.3; }
.card-icon {
  width: 56px; height: 56px;
  background: var(--hrd-gradient);
  border-radius: var(--radius-lg);
  display: flex; align-items: center; justify-content: center;
  color: white; font-size: 1.5rem; font-weight: 800;
  margin-bottom: var(--space-5);
  box-shadow: var(--shadow-glow);
  letter-spacing: -0.05em;
}
.card h3 { font-size: 1.25rem; margin-bottom: var(--space-3); font-weight: 700; }
.card p { color: var(--text-secondary); font-size: 0.95rem; margin-bottom: 0; line-height: 1.7; }

.card-feature {
  background: var(--hrd-gradient-soft);
  border-color: rgba(79, 70, 229, 0.1);
}
.card-feature .card-icon {
  background: var(--hrd-gradient);
}

/* === Section header === */
.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto var(--space-16);
}
.section-eyebrow {
  display: inline-flex; align-items: center; gap: var(--space-2);
  color: var(--hrd-primary);
  font-weight: 600;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-4);
  padding: 0.375rem 1rem;
  background: var(--hrd-primary-50);
  border-radius: var(--radius-full);
}
.section-header h2 { margin-bottom: var(--space-4); }
.section-header p { color: var(--text-secondary); font-size: 1.1rem; line-height: 1.7; }

/* === Table === */
table {
  width: 100%; border-collapse: collapse;
  margin: var(--space-4) 0;
  background: var(--bg-elevated);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-soft);
}
th, td {
  padding: var(--space-3) var(--space-4);
  text-align: left;
  border-bottom: 1px solid var(--border-soft);
}
th { background: var(--bg-secondary); font-weight: 600; font-size: 0.9rem; }
tr:last-child td { border-bottom: none; }
tr:hover td { background: var(--bg-secondary); }

/* === FAQ (现代折叠) === */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: var(--bg-elevated);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-3);
  overflow: hidden;
  transition: all var(--transition);
}
.faq-item:hover { border-color: rgba(79, 70, 229, 0.15); }
.faq-item.active { border-color: var(--hrd-primary); box-shadow: var(--shadow-md); }
.faq-q {
  width: 100%; text-align: left;
  padding: var(--space-5) var(--space-6);
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--text-primary);
  display: flex; justify-content: space-between; align-items: center;
  gap: var(--space-3);
}
.faq-q::after {
  content: "";
  width: 24px; height: 24px;
  background: var(--hrd-primary-50);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%234f46e5' stroke-width='2.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cline x1='12' y1='5' x2='12' y2='19'%3E%3Cline x1='5' y1='12' x2='19' y2='12'%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: center;
  flex-shrink: 0;
  transition: transform var(--transition);
}
.faq-item.active .faq-q::after {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%234f46e5' stroke-width='2.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cline x1='5' y1='12' x2='19' y2='12'%3E%3C/svg%3E");
}
.faq-a {
  padding: 0 var(--space-6) var(--space-5);
  color: var(--text-secondary);
  line-height: 1.7;
  display: none;
}
.faq-item.active .faq-a { display: block; animation: slideDown 0.3s var(--ease-out); }
@keyframes slideDown {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* === Breadcrumb === */
.breadcrumb {
  background: var(--bg-secondary);
  padding: var(--space-4) 0;
  font-size: 0.875rem;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-soft);
}
.breadcrumb a { color: var(--text-secondary); }
.breadcrumb a:hover { color: var(--hrd-primary); }
.breadcrumb-sep { margin: 0 var(--space-2); opacity: 0.5; }

/* === Post content === */
.post-content { max-width: 800px; margin: 0 auto; }
.post-content h2 { margin-top: var(--space-12); font-size: 1.75rem; }
.post-content h3 { margin-top: var(--space-8); font-size: 1.375rem; }
.post-content img { border-radius: var(--radius-lg); margin: var(--space-6) 0; box-shadow: var(--shadow-md); }

/* === Form === */
.form-group { margin-bottom: var(--space-5); }
.form-group label {
  display: block;
  font-weight: 600;
  margin-bottom: var(--space-2);
  font-size: 0.9rem;
  color: var(--text-primary);
}
.form-group input, .form-group textarea, .form-group select {
  width: 100%;
  padding: 0.875rem 1rem;
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-md);
  font-family: inherit;
  font-size: 1rem;
  background: var(--bg-primary);
  transition: all var(--transition);
}
.form-group input:focus, .form-group textarea:focus, .form-group select:focus {
  outline: none;
  border-color: var(--hrd-primary);
  box-shadow: 0 0 0 4px var(--hrd-primary-100);
}
.form-group textarea { min-height: 120px; resize: vertical; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); }
.form-message { padding: var(--space-4); border-radius: var(--radius-md); margin-bottom: var(--space-4); font-weight: 500; }
.form-message.success { background: #d1fae5; color: #065f46; }
.form-message.error { background: #fee2e2; color: #991b1b; }

/* === Footer (深色现代) === */
.site-footer {
  background: var(--bg-dark);
  color: var(--text-inverse);
  padding: var(--space-24) 0 var(--space-8);
  margin-top: var(--space-32);
  position: relative;
  overflow: hidden;
}
.site-footer::before {
  content: "";
  position: absolute; top: 0; left: 0; right: 0; height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}
.footer-col h4 { color: var(--text-inverse); font-size: 0.9rem; margin-bottom: var(--space-4); text-transform: uppercase; letter-spacing: 0.1em; }
.footer-col ul { list-style: none; padding: 0; }
.footer-col li { margin-bottom: var(--space-3); }
.footer-col a { color: rgba(255, 255, 255, 0.6); font-size: 0.9rem; transition: color var(--transition); }
.footer-col a:hover { color: var(--text-inverse); }
.footer-about { color: rgba(255, 255, 255, 0.6); font-size: 0.9rem; line-height: 1.7; }
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: var(--space-6);
  display: flex; justify-content: space-between; align-items: center;
  flex-wrap: wrap; gap: var(--space-4);
  color: rgba(255, 255, 255, 0.5);
  font-size: 0.875rem;
}

/* === Case card (案例) === */
.case-card {
  position: relative;
  background: var(--bg-elevated);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: all 0.4s var(--ease-out);
  display: block;
  color: var(--text-primary);
}
.case-card:hover { box-shadow: var(--shadow-xl); transform: translateY(-4px); }
.case-thumb {
  width: 100%; height: 200px;
  background: var(--hrd-gradient);
  display: flex; align-items: center; justify-content: center;
  color: rgba(255, 255, 255, 0.7);
  font-size: 3.5rem;
  position: relative;
  overflow: hidden;
}
.case-thumb::before {
  content: "";
  position: absolute; inset: 0;
  background: radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.2), transparent 50%);
}
.case-body { padding: var(--space-6); }
.case-meta {
  display: flex; gap: var(--space-2);
  margin-bottom: var(--space-3);
  font-size: 0.75rem;
}
.case-tag {
  background: var(--hrd-primary-50);
  color: var(--hrd-primary);
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  font-weight: 600;
}
.case-card h3 { font-size: 1.125rem; margin-bottom: var(--space-2); font-weight: 700; }
.case-card p { font-size: 0.9rem; color: var(--text-secondary); }

/* === Animations === */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}
@keyframes scaleIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}
.fade-in { animation: fadeInUp 0.7s var(--ease-out) both; }
.fade-in-1 { animation: fadeInUp 0.7s var(--ease-out) 0.1s both; }
.fade-in-2 { animation: fadeInUp 0.7s var(--ease-out) 0.2s both; }
.fade-in-3 { animation: fadeInUp 0.7s var(--ease-out) 0.3s both; }

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s var(--ease-out), transform 0.7s var(--ease-out);
}
.reveal.visible { opacity: 1; transform: translateY(0); }

/* === Utility === */
.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0, 0, 0, 0); white-space: nowrap; border-width: 0;
}
:focus-visible { outline: 2px solid var(--hrd-primary); outline-offset: 2px; border-radius: 4px; }

/* === Responsive === */
@media (max-width: 968px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .hero-stats { gap: var(--space-8); }
  .section { padding: var(--space-16) 0; }
  .section-lg { padding: var(--space-24) 0; }
}
@media (max-width: 640px) {
  :root { --container-padding: var(--space-4); }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: var(--space-8); }
  .form-row { grid-template-columns: 1fr; }
  .menu-toggle { display: flex; align-items: center; justify-content: center; width: 40px; height: 40px; border-radius: var(--radius-md); }
  .main-nav {
    display: none;
    position: absolute; top: 100%; left: 0; right: 0;
    background: var(--bg-primary);
    flex-direction: column; padding: var(--space-4);
    border-top: 1px solid var(--border-soft);
    box-shadow: var(--shadow-md);
    align-items: stretch;
    gap: 0;
    max-height: calc(100vh - 70px);
    overflow-y: auto;
  }
  .main-nav.active { display: flex; }
  .main-nav > a { padding: var(--space-3); border-radius: var(--radius-md); }
  .main-nav > a:not(.btn):hover { background: var(--bg-secondary); }
  .main-nav .nav-item { display: flex; flex-direction: column; }
  .main-nav .nav-item > .nav-link { padding: var(--space-3); border-radius: var(--radius-md); }
  .main-nav .nav-item.open .caret { transform: rotate(180deg); }
  /* 移动端:下拉变成点击展开 */
  .nav-item .dropdown {
    position: static;
    transform: none;
    min-width: 0;
    background: var(--bg-secondary);
    border: none;
    border-radius: var(--radius-md);
    box-shadow: none;
    padding: var(--space-2);
    margin-top: var(--space-2);
    opacity: 1;
    visibility: visible;
    pointer-events: none;
    display: none;
  }
  .nav-item.open .dropdown { display: block; transform: none; pointer-events: auto; }
  .nav-item .dropdown::before { display: none; }
  .dropdown-grid { grid-template-columns: 1fr; }
  .dropdown-item, .dropdown-overview { padding: var(--space-2) var(--space-3); }
  .hero { padding: var(--space-16) 0; }
  .hero-stats { gap: var(--space-6); }
  .hero-stat-num { font-size: 2rem; }
  .section { padding: var(--space-12) 0; }
  .section-lg { padding: var(--space-16) 0; }
  .card { padding: var(--space-6); }
  .site-logo small { display: none; }
}

/* === Print === */
@media print {
  .site-header, .site-footer, .hero-cta, .menu-toggle, .no-print { display: none !important; }
  body { color: #000; background: #fff; }
  .hero { background: white; color: black; padding: 2rem 0; }
  .hero h1, .hero p { color: black; }
}

/* === Admin (后台) === */
.admin-wrap { max-width: 1200px; margin: 0 auto; padding: var(--space-8); }
.admin-topbar {
  background: var(--bg-dark);
  color: var(--text-inverse);
  padding: var(--space-4) var(--space-6);
  display: flex; justify-content: space-between; align-items: center;
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: blur(20px);
  background: rgba(10, 10, 26, 0.95);
}
.admin-topbar a { color: var(--text-inverse); opacity: 0.8; }
.admin-topbar a:hover { opacity: 1; }
.admin-table { width: 100%; border-collapse: collapse; background: var(--bg-elevated); border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow-sm); }
.admin-table th, .admin-table td { padding: var(--space-4); border-bottom: 1px solid var(--border-soft); text-align: left; }
.admin-table th { background: var(--bg-secondary); font-weight: 600; font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--text-secondary); }
.admin-table tr:last-child td { border-bottom: none; }
.admin-table tr:hover td { background: var(--bg-secondary); }
.editor-wrap textarea { font-family: var(--font-mono); font-size: 0.9rem; min-height: 500px; }