/* ===== CSS Variables ===== */
:root {
  --color-primary: #1a3a5c;
  --color-accent: #2563eb;
  --color-gold: #c9973b;
  --color-bg: #f5f6f8;
  --color-bg-alt: #edf0f3;
  --color-text: #333;
  --color-text-light: #666;
  --color-white: #fff;
  --nav-height: 70px;
  --max-width: 1200px;
  --transition-speed: 0.3s;
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--color-text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  text-decoration: none;
  color: inherit;
}

ul {
  list-style: none;
}

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

/* ===== Section Common ===== */
.section {
  padding: 100px 0;
}

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

.section-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--color-primary);
  text-align: center;
  margin-bottom: 60px;
  position: relative;
}

.section-title::after {
  content: "";
  display: block;
  width: 60px;
  height: 3px;
  background: var(--color-gold);
  margin: 16px auto 0;
}

/* ===== Grid Layouts ===== */
.cards-grid {
  display: grid;
  gap: 30px;
}

.two-col {
  grid-template-columns: 1fr 1fr;
}

.three-col {
  grid-template-columns: repeat(3, 1fr);
}

/* ===== Header / Navigation ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  z-index: 1000;
  transition: background-color var(--transition-speed);
  background-color: transparent;
}

.header.scrolled {
  background-color: var(--color-primary);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
}

.nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-white);
  letter-spacing: 2px;
}

.nav-menu {
  display: flex;
  gap: 32px;
}

.nav-menu a {
  color: rgba(255, 255, 255, 0.85);
  font-size: 15px;
  transition: color var(--transition-speed);
  padding-bottom: 4px;
  border-bottom: 2px solid transparent;
}

.nav-menu a:hover {
  color: var(--color-white);
  border-bottom-color: var(--color-gold);
}

/* ===== Hero ===== */
.hero {
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--color-white);
  position: relative;
  overflow: hidden;
  background: linear-gradient(
    135deg,
    #0f1f33 0%,
    #1a3a5c 40%,
    #1e4d7b 70%,
    #0f1f33 100%
  );
}

/* Grid overlay effect */
.hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  animation: gridMove 20s linear infinite;
}

@keyframes gridMove {
  from { transform: translate(0, 0); }
  to { transform: translate(60px, 60px); }
}

/* Floating particles */
.hero::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background:
    radial-gradient(circle at 20% 30%, rgba(201, 151, 59, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 70% 60%, rgba(37, 99, 235, 0.06) 0%, transparent 50%),
    radial-gradient(circle at 40% 80%, rgba(201, 151, 59, 0.05) 0%, transparent 50%);
}

.hero-content {
  position: relative;
  z-index: 1;
  padding: 0 24px;
}

.hero-title {
  font-size: 48px;
  font-weight: 700;
  letter-spacing: 4px;
  margin-bottom: 16px;
}

.hero-subtitle {
  font-size: 18px;
  color: rgba(255, 255, 255, 0.7);
  letter-spacing: 2px;
  margin-bottom: 32px;
}

.hero-tagline {
  font-size: 24px;
  font-weight: 300;
  letter-spacing: 8px;
  color: var(--color-gold);
}

/* Scroll indicator */
.hero-scroll-indicator {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 1;
}

.hero-scroll-indicator span {
  display: block;
  width: 24px;
  height: 24px;
  border-right: 2px solid rgba(255, 255, 255, 0.5);
  border-bottom: 2px solid rgba(255, 255, 255, 0.5);
  transform: rotate(45deg);
  animation: scrollBounce 2s infinite;
}

@keyframes scrollBounce {
  0%, 100% { opacity: 0.3; transform: rotate(45deg) translate(-4px, -4px); }
  50% { opacity: 1; transform: rotate(45deg) translate(4px, 4px); }
}

/* ===== About ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-text p {
  color: var(--color-text-light);
  margin-bottom: 16px;
  font-size: 16px;
  line-height: 1.9;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.stat-card {
  background: var(--color-white);
  padding: 32px 16px;
  text-align: center;
  border-radius: 8px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.stat-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
}

.stat-number {
  display: block;
  font-size: 36px;
  font-weight: 700;
  color: var(--color-gold);
  line-height: 1.2;
}

.stat-unit {
  font-size: 18px;
  font-weight: 400;
}

.stat-label {
  display: block;
  font-size: 14px;
  color: var(--color-text-light);
  margin-top: 8px;
}

/* ===== Solution Cards ===== */
.card {
  background: var(--color-white);
  padding: 48px 32px;
  border-radius: 8px;
  text-align: center;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.1);
}

.card-icon {
  font-size: 48px;
  color: var(--color-accent);
  margin-bottom: 24px;
  display: block;
}

.card h3 {
  font-size: 20px;
  color: var(--color-primary);
  margin-bottom: 16px;
}

.card p {
  color: var(--color-text-light);
  font-size: 15px;
  line-height: 1.8;
}

/* ===== Capability Cards ===== */
.capability-card {
  background: var(--color-white);
  padding: 36px 24px;
  border-radius: 8px;
  text-align: center;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
  border-top: 3px solid transparent;
}

.capability-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
  border-top-color: var(--color-accent);
}

.capability-icon {
  font-size: 40px;
  color: var(--color-accent);
  margin-bottom: 16px;
  display: block;
}

.capability-card h4 {
  font-size: 18px;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.capability-card p {
  color: var(--color-text-light);
  font-size: 14px;
}

/* ===== News ===== */
.news-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
}

.news-column-title {
  font-size: 20px;
  color: var(--color-primary);
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-gold);
}

.news-list li {
  border-bottom: 1px solid #e5e7eb;
}

.news-list li:last-child {
  border-bottom: none;
}

.news-list a {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
  transition: color var(--transition-speed);
}

.news-list a:hover {
  color: var(--color-accent);
}

.news-item-title {
  flex: 1;
  font-size: 15px;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
  padding-right: 16px;
}

.news-date {
  font-size: 13px;
  color: var(--color-text-light);
  flex-shrink: 0;
}

/* ===== Contact ===== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
}

.contact-item {
  margin-bottom: 32px;
}

.contact-label {
  display: block;
  font-size: 14px;
  color: var(--color-text-light);
  margin-bottom: 8px;
}

.contact-value {
  font-size: 16px;
  color: var(--color-text);
}

.map-frame {
  width: 100%;
  height: 280px;
  border: 0;
  border-radius: 8px;
}

/* ===== Footer ===== */
.footer {
  background-color: var(--color-primary);
  color: rgba(255, 255, 255, 0.7);
  padding: 48px 0;
}

.footer-content {
  text-align: center;
}

.footer-info p {
  font-size: 14px;
  line-height: 2;
}

/* ===== Scroll Animations ===== */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Responsive: Tablet ===== */
@media (max-width: 992px) {
  .three-col {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-grid,
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .about-stats {
    grid-template-columns: repeat(3, 1fr);
  }

  .hero-title {
    font-size: 36px;
  }
}

/* ===== Responsive: Mobile ===== */
@media (max-width: 768px) {
  .nav-menu {
    display: none;
  }

  .section {
    padding: 60px 0;
  }

  .section-title {
    font-size: 26px;
    margin-bottom: 40px;
  }

  .three-col {
    grid-template-columns: 1fr;
  }

  .two-col {
    grid-template-columns: 1fr;
  }

  .about-stats {
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
  }

  .stat-card {
    padding: 20px 8px;
  }

  .stat-number {
    font-size: 28px;
  }

  .hero-title {
    font-size: 28px;
    letter-spacing: 2px;
  }

  .hero-tagline {
    font-size: 18px;
    letter-spacing: 4px;
  }

  .hero-subtitle {
    font-size: 14px;
  }

  .footer-content {
    text-align: center;
  }

  .news-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

/* ===== News Detail Page ===== */
.article-page {
  padding: 120px 0 80px;
  min-height: 100vh;
}

.article {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 24px;
}

.article-date {
  display: inline-block;
  font-size: 14px;
  color: var(--color-text-light);
  background: var(--color-bg);
  padding: 6px 14px;
  border-radius: 4px;
  margin-bottom: 20px;
}

.article-title {
  font-size: 28px;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.4;
  margin-bottom: 24px;
  padding-bottom: 20px;
  border-bottom: 2px solid var(--color-gold);
}

.article-body {
  font-size: 17px;
  line-height: 1.9;
  color: var(--color-text);
}

.article-body p {
  margin-bottom: 16px;
}

.article-back {
  display: inline-block;
  margin-top: 40px;
  padding: 10px 24px;
  background: var(--color-primary);
  color: var(--color-white);
  border-radius: 4px;
  font-size: 15px;
  transition: background var(--transition-speed);
}

.article-back:hover {
  background: var(--color-accent);
}