/* ========================================
   Tencent Official Website - Homepage
   ======================================== */

/* --- CSS Variables / Design Tokens --- */
:root {
  --color-primary: #0066FF;
  --color-primary-dark: #0052CC;
  --color-primary-light: #4D94FF;
  --color-accent: #00E5A0;
  --color-accent-dark: #00B883;
  --color-dark: #0A1628;
  --color-dark-2: #13203A;
  --color-dark-3: #1A2B4A;
  --color-gray-100: #F5F7FA;
  --color-gray-200: #E8ECF1;
  --color-gray-300: #C8CFD8;
  --color-gray-400: #9BA5B0;
  --color-gray-500: #6B7A8A;
  --color-gray-600: #4A5568;
  --color-white: #FFFFFF;
  --color-bg: #FFFFFF;
  --font-sans: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --max-width: 1200px;
  --header-height: 72px;
  --border-radius: 12px;
  --border-radius-lg: 20px;
  --shadow-sm: 0 2px 8px rgba(10, 22, 40, 0.06);
  --shadow-md: 0 8px 30px rgba(10, 22, 40, 0.1);
  --shadow-lg: 0 20px 60px rgba(10, 22, 40, 0.15);
  --shadow-glow: 0 0 40px rgba(0, 102, 255, 0.15);
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  color: var(--color-dark);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

ul { list-style: none; }

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

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

.section {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-header h2 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
  position: relative;
  display: inline-block;
}

.section-header h2::after {
  content: '';
  display: block;
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  border-radius: 2px;
  margin: 16px auto 0;
}

.section-desc {
  font-size: 1.125rem;
  color: var(--color-gray-500);
  max-width: 600px;
  margin: 0 auto;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 50px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  border: 2px solid transparent;
  font-family: inherit;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: var(--color-white);
  box-shadow: 0 4px 20px rgba(0, 102, 255, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0, 102, 255, 0.45);
}

.btn-outline {
  background: transparent;
  color: var(--color-white);
  border-color: rgba(255, 255, 255, 0.3);
}

.btn-outline:hover {
  border-color: var(--color-white);
  background: rgba(255, 255, 255, 0.1);
  transform: translateY(-2px);
}

.btn-link {
  color: var(--color-primary);
  padding: 8px 0;
  font-weight: 500;
}

.btn-link:hover {
  color: var(--color-primary-dark);
  gap: 12px;
}

.btn-lg {
  padding: 18px 40px;
  font-size: 1.125rem;
}

.arrow {
  transition: transform var(--transition);
}

.btn-link:hover .arrow {
  transform: translateX(4px);
}

/* --- Header / Navigation --- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  transition: all var(--transition);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1.5rem;
  font-weight: 700;
}

.logo-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  color: var(--color-white);
  border-radius: 8px;
  font-size: 0.875rem;
}

.logo-text {
  color: var(--color-dark);
}

.main-nav ul {
  display: flex;
  align-items: center;
  gap: 8px;
}

.main-nav a {
  display: block;
  padding: 8px 20px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-gray-600);
  border-radius: 8px;
  transition: all var(--transition);
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--color-primary);
  background: rgba(0, 102, 255, 0.06);
}

.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.mobile-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-dark);
  border-radius: 2px;
  transition: all var(--transition);
}

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

.hero-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--color-dark) 0%, var(--color-dark-2) 40%, var(--color-dark-3) 100%);
  z-index: -2;
}

.hero-bg::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -30%;
  width: 80vw;
  height: 80vw;
  background: radial-gradient(circle, rgba(0, 102, 255, 0.12) 0%, transparent 70%);
  animation: heroGlow 8s ease-in-out infinite alternate;
}

.hero-bg::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -20%;
  width: 60vw;
  height: 60vw;
  background: radial-gradient(circle, rgba(0, 229, 160, 0.08) 0%, transparent 70%);
  animation: heroGlow 10s ease-in-out 2s infinite alternate;
}

@keyframes heroGlow {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(-30px, 30px) scale(1.1); }
}

.hero-content {
  position: relative;
  z-index: 1;
  padding: 60px 0;
  max-width: 720px;
}

.hero-title {
  font-size: 4rem;
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
  animation: fadeInUp 0.8s ease-out;
}

.hero-title-line {
  display: block;
  color: var(--color-white);
}

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

.hero-subtitle {
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 40px;
  line-height: 1.8;
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.hero-actions {
  display: flex;
  gap: 16px;
  animation: fadeInUp 0.8s ease-out 0.4s both;
}

/* --- Hero Stats --- */
.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  margin-top: 64px;
  padding-top: 48px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  animation: fadeInUp 0.8s ease-out 0.6s both;
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--color-white);
  line-height: 1;
}

.stat-suffix {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary-light);
  margin-left: 2px;
  line-height: 1;
  display: inline;
}

.stat-label {
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.5);
  margin-top: 8px;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* --- About Section --- */
.about {
  background: var(--color-gray-100);
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.about-text p {
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--color-gray-600);
  margin-bottom: 20px;
}

.about-values {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.value-card {
  background: var(--color-white);
  padding: 32px 24px;
  border-radius: var(--border-radius);
  text-align: center;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
}

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

.value-icon {
  font-size: 2.5rem;
  margin-bottom: 16px;
  display: block;
}

.value-card h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--color-dark);
}

.value-card p {
  font-size: 0.875rem;
  color: var(--color-gray-500);
}

/* --- Services Section --- */
.services {
  background: var(--color-white);
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.service-card {
  background: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--border-radius-lg);
  padding: 40px 32px;
  transition: all var(--transition);
}

.service-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.service-icon {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
}

.service-icon svg {
  width: 28px;
  height: 28px;
}

.service-icon-blue {
  background: rgba(0, 102, 255, 0.1);
  color: var(--color-primary);
}

.service-icon-green {
  background: rgba(0, 229, 160, 0.1);
  color: var(--color-accent-dark);
}

.service-icon-orange {
  background: rgba(255, 152, 0, 0.1);
  color: #F57C00;
}

.service-icon-purple {
  background: rgba(156, 39, 176, 0.1);
  color: #7B1FA2;
}

.service-icon-red {
  background: rgba(244, 67, 54, 0.1);
  color: #D32F2F;
}

.service-icon-cyan {
  background: rgba(0, 188, 212, 0.1);
  color: #0097A7;
}

.service-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--color-dark);
}

.service-card p {
  font-size: 0.9375rem;
  color: var(--color-gray-500);
  line-height: 1.7;
  margin-bottom: 20px;
}

.service-link {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-primary);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: gap var(--transition);
}

.service-link:hover {
  gap: 8px;
}

/* --- News Section --- */
.news {
  background: var(--color-gray-100);
}

.news-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 32px;
}

.news-card {
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  background: var(--color-white);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
}

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

.news-image {
  height: 280px;
  background-size: cover;
  background-position: center;
  position: relative;
}

.news-image-1 {
  background: linear-gradient(135deg, var(--color-primary-dark), var(--color-dark-3));
  position: relative;
  overflow: hidden;
}

.news-image-1::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 30%, rgba(0, 102, 255, 0.3) 0%, transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(0, 229, 160, 0.15) 0%, transparent 50%);
}

.news-image-1::after {
  content: '';
  position: absolute;
  inset: 0;
  background:
    linear-gradient(45deg, transparent 65%, rgba(255,255,255,0.03) 100%);
}

.news-tag {
  position: absolute;
  top: 20px;
  left: 20px;
  padding: 6px 16px;
  background: var(--color-primary);
  color: var(--color-white);
  font-size: 0.8125rem;
  font-weight: 600;
  border-radius: 20px;
  z-index: 1;
}

.news-content {
  padding: 32px;
}

.news-content time {
  font-size: 0.875rem;
  color: var(--color-gray-400);
  display: block;
  margin-bottom: 8px;
}

.news-content h3 {
  font-size: 1.375rem;
  font-weight: 700;
  margin-bottom: 12px;
  line-height: 1.4;
}

.news-content p {
  color: var(--color-gray-500);
  line-height: 1.7;
  margin-bottom: 16px;
}

.news-sidebar {
  display: flex;
  flex-direction: column;
  gap: 0;
  background: var(--color-white);
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.news-card-mini {
  padding: 24px 28px;
  border-bottom: 1px solid var(--color-gray-200);
  transition: background var(--transition);
}

.news-card-mini:last-child {
  border-bottom: none;
}

.news-card-mini:hover {
  background: var(--color-gray-100);
}

.news-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 8px;
}

.news-meta time,
.news-category {
  font-size: 0.8125rem;
  color: var(--color-gray-400);
}

.news-category {
  padding: 2px 10px;
  background: rgba(0, 102, 255, 0.08);
  color: var(--color-primary);
  border-radius: 12px;
  font-weight: 500;
}

.news-card-mini h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 6px;
  line-height: 1.4;
}

.news-card-mini p {
  font-size: 0.875rem;
  color: var(--color-gray-500);
  line-height: 1.6;
}

.news-more {
  display: block;
  padding: 20px 28px;
  text-align: center;
  font-weight: 500;
  color: var(--color-primary);
  border-top: 1px solid var(--color-gray-200);
  transition: all var(--transition);
}

.news-more:hover {
  background: var(--color-gray-100);
}

/* --- CTA Section --- */
.cta {
  background: linear-gradient(135deg, var(--color-dark) 0%, var(--color-dark-2) 100%);
  position: relative;
  overflow: hidden;
}

.cta::before {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 50%;
  height: 100%;
  background: radial-gradient(circle at center, rgba(0, 102, 255, 0.1) 0%, transparent 70%);
}

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

.cta-content h2 {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 16px;
}

.cta-content p {
  font-size: 1.125rem;
  color: rgba(255, 255, 255, 0.7);
  max-width: 560px;
  margin: 0 auto 40px;
}

.cta-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
}

/* --- Footer --- */
.site-footer {
  background: var(--color-dark);
  color: rgba(255, 255, 255, 0.8);
  padding: 80px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1.375rem;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 16px;
}

.footer-desc {
  font-size: 0.9375rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.5);
  margin-bottom: 24px;
}

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

.social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.06);
  font-size: 0.8125rem;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.6);
  transition: all var(--transition);
}

.social-link:hover {
  background: var(--color-primary);
  color: var(--color-white);
  transform: translateY(-2px);
}

.footer-col h4 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-white);
  margin-bottom: 20px;
}

.footer-col ul li {
  margin-bottom: 12px;
}

.footer-col ul a {
  font-size: 0.9375rem;
  color: rgba(255, 255, 255, 0.5);
  transition: all var(--transition);
}

.footer-col ul a:hover {
  color: var(--color-primary-light);
  padding-left: 4px;
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 24px 0;
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.3);
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  .hero-title { font-size: 3rem; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); gap: 32px; }
  .about-grid { grid-template-columns: 1fr; gap: 40px; }
  .services-grid { grid-template-columns: repeat(2, 1fr); }
  .news-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: repeat(2, 1fr); gap: 40px; }
}

@media (max-width: 768px) {
  .section { padding: 64px 0; }
  .section-header { margin-bottom: 40px; }
  .section-header h2 { font-size: 1.875rem; }

  .main-nav { display: none; }
  .mobile-toggle { display: flex; }

  .hero-title { font-size: 2.25rem; }
  .hero-subtitle { font-size: 1rem; }
  .hero-actions { flex-direction: column; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); gap: 24px; margin-top: 40px; padding-top: 32px; }
  .stat-number { font-size: 2rem; }

  .about-grid { grid-template-columns: 1fr; gap: 32px; }
  .about-values { grid-template-columns: 1fr 1fr; gap: 16px; }
  .value-card { padding: 24px 16px; }

  .services-grid { grid-template-columns: 1fr; }

  .news-image { height: 200px; }
  .news-content { padding: 24px; }
  .news-card-mini { padding: 20px; }
  .news-sidebar { gap: 0; }

  .cta-content h2 { font-size: 1.875rem; }
  .cta-actions { flex-direction: column; align-items: center; }

  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
}

@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .hero-title { font-size: 1.875rem; }
  .hero-stats { grid-template-columns: 1fr 1fr; gap: 16px; }
  .about-values { grid-template-columns: 1fr; }
}