/* ============================================================
   冀算云枢 JiSuan CloudHub — 主样式表
   设计语言：极简克制 · 高级信息层级 · 流畅体验
   色彩系统：科技深蓝系 #165DFF
   字体：Inter (English) / 思源黑体 (Chinese) / JetBrains Mono (Code)
   网格系统：8px 基准, 最大内容宽度 1280px
   ============================================================ */

/* --- CSS Variables --- */
:root {
  /* Brand Colors */
  --color-primary: #165DFF;
  --color-primary-hover: #0E42D2;
  --color-primary-light: rgba(22, 93, 255, 0.08);
  --color-primary-lighter: rgba(22, 93, 255, 0.04);
  --color-accent: #00C6FF;
  --color-accent-hover: #00A8E0;
  --color-success: #00B42A;
  --color-warning: #FF7D00;
  --color-danger: #F53F3F;

  /* Neutral Colors - Light Mode */
  --color-bg: #F7F8FA;
  --color-bg-alt: #F0F1F5;
  --color-card: #FFFFFF;
  --color-card-hover: #FAFBFC;
  --color-text: #1D2129;
  --color-text-secondary: #4E5969;
  --color-text-tertiary: #86909C;
  --color-border: #E5E6EB;
  --color-border-light: #F0F1F5;
  --color-overlay: rgba(0, 0, 0, 0.04);

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.08);
  --shadow-xl: 0 16px 40px rgba(0, 0, 0, 0.10);
  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.04), 0 8px 24px rgba(0, 0, 0, 0.06);
  --shadow-card-hover: 0 4px 12px rgba(0, 0, 0, 0.06), 0 12px 40px rgba(0, 0, 0, 0.10);

  /* Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Typography */
  --font-sans: 'Inter', 'HarmonyOS Sans', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'Consolas', monospace;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 300ms ease;
  --transition-bounce: 200ms cubic-bezier(0.34, 1.56, 0.64, 1);

  /* Layout */
  --container-width: 1280px;
  --navbar-height: 64px;
}

/* --- Dark Mode --- */
[data-theme="dark"] {
  --color-bg: #0A0A0F;
  --color-bg-alt: #10101A;
  --color-card: #14141F;
  --color-card-hover: #1A1A2E;
  --color-text: #E5E6EB;
  --color-text-secondary: #86909C;
  --color-text-tertiary: #6B6F7A;
  --color-border: #27273A;
  --color-border-light: #1E1E30;
  --color-overlay: rgba(255, 255, 255, 0.04);

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.4);
  --shadow-xl: 0 16px 40px rgba(0, 0, 0, 0.5);
  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.3);
  --shadow-card-hover: 0 4px 12px rgba(0, 0, 0, 0.4), 0 12px 40px rgba(0, 0, 0, 0.5);
}

/* --- Reset & Base --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  overflow-x: hidden;
  transition: background-color var(--transition-base), color var(--transition-base);
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

ul, ol {
  list-style: none;
}

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

/* --- Container --- */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

@media (max-width: 768px) {
  .container { padding: 0 16px; }
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.02em;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  font-size: 14px;
  font-weight: 500;
  line-height: 1;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  transition: all var(--transition-base);
  white-space: nowrap;
  cursor: pointer;
  text-decoration: none;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

.btn svg {
  flex-shrink: 0;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  color: #ffffff;
  border-color: transparent;
  box-shadow: 0 2px 8px rgba(22, 93, 255, 0.25);
}

.btn-primary:hover {
  box-shadow: 0 4px 16px rgba(22, 93, 255, 0.35);
  background: linear-gradient(135deg, var(--color-primary-hover), var(--color-accent-hover));
}

.btn-outline {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}

.btn-outline:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: var(--color-primary-light);
}

.btn-sm {
  padding: 8px 16px;
  font-size: 13px;
}

.btn-lg {
  padding: 14px 28px;
  font-size: 16px;
  border-radius: var(--radius-md);
}

/* --- Navigation --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--navbar-height);
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid transparent;
  transition: all var(--transition-base);
}

[data-theme="dark"] .navbar {
  background: rgba(10, 10, 15, 0.8);
}

.navbar.scrolled {
  border-bottom-color: var(--color-border-light);
  box-shadow: var(--shadow-sm);
}

.navbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav-left {
  display: flex;
  align-items: center;
  gap: 40px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.logo-icon {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.logo-icon svg {
  display: block;
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-name {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--color-text);
  line-height: 1.2;
}

.logo-sub {
  font-size: 10px;
  font-weight: 500;
  color: var(--color-text-tertiary);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  line-height: 1;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link {
  padding: 8px 14px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-secondary);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.nav-link:hover {
  color: var(--color-text);
  background: var(--color-overlay);
}

.nav-link.active {
  color: var(--color-primary);
  background: var(--color-primary-light);
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

.theme-toggle {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--color-text-tertiary);
  transition: all var(--transition-fast);
}

.theme-toggle:hover {
  background: var(--color-overlay);
  color: var(--color-text);
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 28px;
  padding: 4px;
}

.menu-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all var(--transition-base);
}

/* --- Mobile Navigation --- */
@media (max-width: 1024px) {
  .nav-links {
    position: fixed;
    top: var(--navbar-height);
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--color-card);
    border-bottom: 1px solid var(--color-border);
    padding: 16px;
    gap: 4px;
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: all var(--transition-slow);
  }

  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .nav-link {
    width: 100%;
    padding: 12px 16px;
    font-size: 16px;
  }

  .menu-toggle {
    display: flex;
  }

  .menu-toggle.open span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }
  .menu-toggle.open span:nth-child(2) {
    opacity: 0;
  }
  .menu-toggle.open span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .nav-right .btn {
    display: none;
  }
}

/* --- Hero Section --- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: var(--navbar-height);
  overflow: hidden;
}

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

.hero-grid {
  position: absolute;
  inset: 0;
  background-image: 
    linear-gradient(var(--color-border-light) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-border-light) 1px, transparent 1px);
  background-size: 80px 80px;
  mask-image: radial-gradient(ellipse 60% 50% at 50% 50%, black 30%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 60% 50% at 50% 50%, black 30%, transparent 70%);
}

.hero-particles {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.hero-particle {
  position: absolute;
  width: 3px;
  height: 3px;
  background: var(--color-primary);
  border-radius: 50%;
  opacity: 0.4;
  animation: float-particle linear infinite;
}

@keyframes float-particle {
  0% { transform: translateY(100vh) scale(0); opacity: 0; }
  10% { opacity: 0.4; transform: scale(1); }
  90% { opacity: 0.4; }
  100% { transform: translateY(-100px) scale(0); opacity: 0; }
}

.hero-inner {
  position: relative;
  display: flex;
  align-items: center;
  gap: 60px;
  padding: 80px 0;
}

.hero-content {
  flex: 1;
  max-width: 600px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  font-size: 13px;
  font-weight: 500;
  color: var(--color-primary);
  background: var(--color-primary-light);
  border: 1px solid rgba(22, 93, 255, 0.15);
  border-radius: var(--radius-full);
  margin-bottom: 24px;
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
  animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.hero-title {
  font-size: 56px;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 20px;
}

.gradient-text {
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: 18px;
  line-height: 1.7;
  color: var(--color-text-secondary);
  margin-bottom: 32px;
}

.hero-actions {
  display: flex;
  gap: 12px;
  margin-bottom: 48px;
}

.hero-stats {
  display: flex;
  gap: 32px;
}

.stat-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.stat-num {
  font-size: 32px;
  font-weight: 700;
  color: var(--color-text);
  line-height: 1;
}

.stat-unit {
  font-size: 20px;
  font-weight: 500;
  color: var(--color-text-tertiary);
}

.stat-label {
  font-size: 13px;
  color: var(--color-text-tertiary);
  font-weight: 400;
}

/* Hero Visual */
.hero-visual {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  max-width: 520px;
}

.visual-3d {
  position: relative;
  width: 400px;
  height: 400px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.orbit-ring {
  position: absolute;
  border: 1px solid;
  border-radius: 50%;
  animation: rotate-ring linear infinite;
}

.ring-outer {
  width: 380px;
  height: 380px;
  border-color: rgba(22, 93, 255, 0.15);
  animation-duration: 20s;
}

.ring-middle {
  width: 280px;
  height: 280px;
  border-color: rgba(0, 198, 255, 0.2);
  animation-duration: 15s;
  animation-direction: reverse;
}

.ring-inner {
  width: 180px;
  height: 180px;
  border-color: rgba(22, 93, 255, 0.25);
  animation-duration: 10s;
}

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

.orbit-node {
  position: absolute;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-primary);
  box-shadow: 0 0 20px rgba(22, 93, 255, 0.5);
}

.node-1 { top: 50%; left: 0; margin-top: -6px; }
.node-2 { top: 10%; left: 50%; margin-left: -6px; }
.node-3 { top: 50%; right: 0; margin-top: -6px; }
.node-4 { bottom: 10%; left: 50%; margin-left: -6px; }

.orbit-center {
  position: absolute;
  width: 80px;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: radial-gradient(circle, rgba(22, 93, 255, 0.1) 0%, transparent 70%);
}

.data-flow {
  position: absolute;
  width: 2px;
  height: 60px;
  background: linear-gradient(to top, transparent, var(--color-accent), transparent);
  opacity: 0.6;
  animation: flow-up 2s ease-in-out infinite;
}

.flow-1 { left: 30%; top: 20%; animation-delay: 0s; }
.flow-2 { left: 60%; top: 30%; animation-delay: 0.7s; height: 40px; }
.flow-3 { left: 45%; top: 60%; animation-delay: 1.4s; height: 50px; }

@keyframes flow-up {
  0% { transform: translateY(0) scaleY(1); opacity: 0; }
  50% { opacity: 0.6; }
  100% { transform: translateY(-80px) scaleY(0.5); opacity: 0; }
}

/* Hero Scroll */
.hero-scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--color-text-tertiary);
  font-size: 12px;
  opacity: 0.6;
  animation: bounce-scroll 2s infinite;
}

@keyframes bounce-scroll {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(8px); }
}

.scroll-arrow {
  width: 20px;
  height: 20px;
  border-right: 2px solid var(--color-text-tertiary);
  border-bottom: 2px solid var(--color-text-tertiary);
  transform: rotate(45deg);
}

@media (max-width: 1024px) {
  .hero-inner {
    flex-direction: column;
    padding: 60px 0;
    gap: 40px;
    text-align: center;
  }

  .hero-content { max-width: 100%; }
  .hero-title { font-size: 40px; }
  .hero-desc { font-size: 16px; }
  .hero-actions { justify-content: center; }
  .hero-stats { justify-content: center; flex-wrap: wrap; gap: 24px; }
  .hero-visual { display: none; }
}

@media (max-width: 640px) {
  .hero-title { font-size: 32px; }
  .hero-stats { gap: 16px; }
  .stat-num { font-size: 24px; }
  .hero-actions { flex-direction: column; align-items: center; }
}

/* --- Sections --- */
.section {
  padding: 100px 0;
}

.section-alt {
  background: var(--color-bg-alt);
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

.section-tag {
  display: inline-block;
  padding: 4px 14px;
  font-size: 12px;
  font-weight: 600;
  color: var(--color-primary);
  background: var(--color-primary-light);
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.section-title {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.section-desc {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

@media (max-width: 768px) {
  .section { padding: 60px 0; }
  .section-title { font-size: 28px; }
  .section-header { margin-bottom: 40px; }
}

/* --- Platform Cards Grid --- */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.platform-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 32px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
  cursor: pointer;
  text-decoration: none;
  color: inherit;
}

.platform-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card-hover);
  border-color: transparent;
}

.card-icon {
  width: 52px;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: var(--color-primary-light);
  color: var(--icon-color, var(--color-primary));
  flex-shrink: 0;
}

.platform-card h3 {
  font-size: 18px;
  font-weight: 600;
}

.platform-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  flex: 1;
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.card-tags span {
  padding: 3px 10px;
  font-size: 12px;
  font-weight: 500;
  color: var(--color-text-tertiary);
  background: var(--color-bg);
  border-radius: var(--radius-full);
}

.card-arrow {
  position: absolute;
  top: 32px;
  right: 32px;
  color: var(--color-text-tertiary);
  transition: all var(--transition-fast);
}

.platform-card:hover .card-arrow {
  color: var(--color-primary);
  transform: translateX(4px);
}

@media (max-width: 1024px) {
  .platform-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  .platform-grid { grid-template-columns: 1fr; }
  .platform-card { padding: 24px; }
}

/* --- Features Grid --- */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  padding: 32px;
  border-radius: var(--radius-md);
  background: var(--color-card);
  border: 1px solid var(--color-border);
  transition: all var(--transition-base);
}

.feature-card:hover {
  border-color: var(--color-primary-light);
  box-shadow: var(--shadow-md);
}

.feature-num {
  font-size: 32px;
  font-weight: 800;
  color: var(--color-primary);
  opacity: 0.15;
  margin-bottom: 16px;
  line-height: 1;
}

.feature-card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 12px;
}

.feature-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

@media (max-width: 1024px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  .features-grid { grid-template-columns: 1fr; }
  .feature-card { padding: 24px; }
}

/* --- Solutions --- */
.solutions-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.solution-card {
  padding: 32px 24px;
  text-align: center;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
}

.solution-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card-hover);
}

.solution-icon {
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: color-mix(in srgb, var(--sol-color, var(--color-primary)) 10%, transparent);
  color: var(--sol-color, var(--color-primary));
  margin: 0 auto 20px;
}

.solution-card h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 10px;
}

.solution-card p {
  font-size: 13px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

@media (max-width: 1024px) {
  .solutions-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  .solutions-grid { grid-template-columns: 1fr; }
}

/* --- CTA Section --- */
.cta-section {
  padding-bottom: 0;
}

.cta-card {
  background: linear-gradient(135deg, #165DFF 0%, #0E42D2 50%, #722ED1 100%);
  border-radius: var(--radius-xl);
  padding: 80px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 30% 50%, rgba(0, 198, 255, 0.2) 0%, transparent 60%),
              radial-gradient(circle at 70% 50%, rgba(114, 46, 209, 0.2) 0%, transparent 60%);
  pointer-events: none;
}

.cta-content {
  position: relative;
  z-index: 1;
}

.cta-content h2 {
  font-size: 36px;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 16px;
}

.cta-content p {
  font-size: 18px;
  color: rgba(255, 255, 255, 0.8);
  margin-bottom: 32px;
}

.cta-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
}

.cta-card .btn-outline {
  border-color: rgba(255, 255, 255, 0.3);
  color: #ffffff;
}

.cta-card .btn-outline:hover {
  border-color: #ffffff;
  background: rgba(255, 255, 255, 0.1);
}

.cta-card .btn-primary {
  background: #ffffff;
  color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

.cta-card .btn-primary:hover {
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.3);
}

@media (max-width: 768px) {
  .cta-card { padding: 40px 24px; }
  .cta-content h2 { font-size: 28px; }
  .cta-content p { font-size: 16px; }
  .cta-actions { flex-direction: column; align-items: center; }
}

/* --- Footer --- */
.footer {
  background: var(--color-card);
  border-top: 1px solid var(--color-border);
  padding: 60px 0 40px;
  margin-top: 100px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 48px;
}

.footer-brand .logo {
  margin-bottom: 16px;
}

.footer-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
  max-width: 280px;
}

.footer-social {
  display: flex;
  gap: 12px;
}

.footer-social a {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--color-text-tertiary);
  background: var(--color-bg);
  transition: all var(--transition-fast);
}

.footer-social a:hover {
  color: var(--color-primary);
  background: var(--color-primary-light);
}

.footer-col h4 {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--color-text);
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-col ul a {
  font-size: 14px;
  color: var(--color-text-secondary);
  transition: color var(--transition-fast);
}

.footer-col ul a:hover {
  color: var(--color-primary);
}

.footer-bottom {
  padding-top: 32px;
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.footer-company {
  margin-bottom: 16px;
}

.footer-company p {
  font-size: 13px;
  color: var(--color-text-tertiary);
  line-height: 2;
}

.footer-copyright p {
  font-size: 12px;
  color: var(--color-text-tertiary);
  line-height: 1.8;
}

@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  .footer-grid { grid-template-columns: 1fr; }
  .footer { padding: 40px 0 24px; }
  .footer-desc { max-width: 100%; }
}

/* --- Animations --- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.animate-in {
  animation: fadeInUp 0.6s ease forwards;
}

/* --- Sub-page Hero --- */
.page-hero {
  padding: 120px 0 60px;
  text-align: center;
  background: var(--color-bg-alt);
  border-bottom: 1px solid var(--color-border-light);
}

.page-hero h1 {
  font-size: 40px;
  font-weight: 700;
  margin-bottom: 12px;
}

.page-hero p {
  font-size: 16px;
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* --- GPU Instance Cards --- */
.gpu-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.gpu-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px;
  transition: all var(--transition-base);
}

.gpu-card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
}

.gpu-card .gpu-name {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 4px;
}

.gpu-card .gpu-spec {
  font-size: 13px;
  color: var(--color-text-tertiary);
  margin-bottom: 16px;
}

.gpu-card .gpu-price {
  font-size: 28px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 4px;
}

.gpu-card .gpu-price span {
  font-size: 14px;
  font-weight: 400;
  color: var(--color-text-tertiary);
}

.gpu-card .gpu-status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 500;
  color: var(--color-success);
  margin-bottom: 16px;
}

.gpu-card .gpu-status::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-success);
}

/* --- Tech News Cards --- */
.news-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.news-card {
  display: flex;
  gap: 20px;
  padding: 24px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
}

.news-card:hover {
  box-shadow: var(--shadow-card-hover);
}

.news-card .news-tag {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.news-card h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
}

.news-card p {
  font-size: 13px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* --- Marketplace Products --- */
.product-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.product-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: all var(--transition-base);
}

.product-card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
}

.product-card .product-img {
  aspect-ratio: 16/10;
  background: var(--color-bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
}

.product-card .product-info {
  padding: 16px 20px 20px;
}

.product-card .product-name {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 4px;
}

.product-card .product-meta {
  font-size: 12px;
  color: var(--color-text-tertiary);
  margin-bottom: 12px;
}

.product-card .product-price {
  font-size: 20px;
  font-weight: 700;
  color: var(--color-danger);
}

/* --- Task Listings --- */
.task-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.task-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 24px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
}

.task-item:hover {
  box-shadow: var(--shadow-card-hover);
}

.task-item .task-info h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 6px;
}

.task-item .task-info p {
  font-size: 13px;
  color: var(--color-text-secondary);
}

.task-item .task-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-shrink: 0;
}

.task-item .task-budget {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-primary);
}

.task-item .task-deadline {
  font-size: 12px;
  color: var(--color-text-tertiary);
}

/* --- Community Posts --- */
.post-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.post-item {
  padding: 20px 24px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
}

.post-item:hover {
  border-color: var(--color-primary-light);
}

.post-item .post-title {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
}

.post-item .post-meta {
  display: flex;
  gap: 16px;
  font-size: 12px;
  color: var(--color-text-tertiary);
}

/* --- About Page --- */
.about-info {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: start;
}

.about-info h2 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 20px;
}

.about-info p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}

.team-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.team-card {
  text-align: center;
  padding: 32px 20px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.team-card .team-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--color-primary-light);
  margin: 0 auto 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  font-weight: 700;
  color: var(--color-primary);
}

.team-card h4 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
}

.team-card p {
  font-size: 13px;
  color: var(--color-text-tertiary);
}

/* --- Contact Section --- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}

.contact-info-item {
  display: flex;
  gap: 16px;
  margin-bottom: 24px;
}

.contact-info-item .contact-icon {
  width: 44px;
  height: 44px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: var(--color-primary-light);
  color: var(--color-primary);
}

.contact-info-item h4 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 4px;
}

.contact-info-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* --- Login/Register --- */
.auth-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 24px 60px;
}

.auth-card {
  width: 100%;
  max-width: 440px;
  padding: 40px;
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
}

.auth-card h2 {
  font-size: 24px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 8px;
}

.auth-card .auth-sub {
  text-align: center;
  color: var(--color-text-secondary);
  font-size: 14px;
  margin-bottom: 32px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 8px;
  color: var(--color-text);
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 10px 14px;
  font-size: 14px;
  font-family: inherit;
  color: var(--color-text);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  outline: none;
  transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

.form-group textarea {
  min-height: 100px;
  resize: vertical;
}

.form-group .btn {
  width: 100%;
  justify-content: center;
}

/* --- Utility Classes --- */
.text-primary { color: var(--color-primary); }
.text-center { text-align: center; }
.mt-4 { margin-top: 16px; }
.mt-8 { margin-top: 32px; }
.mb-4 { margin-bottom: 16px; }
.mb-8 { margin-bottom: 32px; }
.flex { display: flex; }
.flex-between { display: flex; justify-content: space-between; align-items: center; }
.gap-2 { gap: 8px; }
.gap-4 { gap: 16px; }
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }

@media (max-width: 1024px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .about-info, .contact-grid { grid-template-columns: 1fr; }
  .team-grid { grid-template-columns: repeat(2, 1fr); }
  .news-grid, .gpu-grid { grid-template-columns: 1fr; }
  .product-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .team-grid, .product-grid { grid-template-columns: 1fr; }
  .task-item { flex-direction: column; align-items: flex-start; }
  .page-hero { padding: 100px 0 40px; }
  .page-hero h1 { font-size: 28px; }
}

/* --- Image placeholders --- */
.placeholder-img {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-primary-light), var(--color-bg-alt));
  color: var(--color-primary);
  font-size: 36px;
  font-weight: 600;
  opacity: 0.5;
}