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

:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #3b82f6;
  --accent: #06b6d4;
  --text: #1e293b;
  --text-light: #64748b;
  --text-lighter: #94a3b8;
  --bg: #ffffff;
  --bg-light: #f8fafc;
  --bg-dark: #0f172a;
  --border: #e2e8f0;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 20px 40px -12px rgba(0, 0, 0, 0.12);
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  overflow-x: hidden;
}

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

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

ul {
  list-style: none;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Navbar ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 20px 0;
  transition: var(--transition);
  background: transparent;
}

.navbar.scrolled {
  padding: 12px 0;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 20px;
  color: var(--bg);
  transition: var(--transition);
}

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

.logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 20px;
  font-weight: 800;
}

.nav-links {
  display: flex;
  gap: 36px;
}

.nav-links a {
  font-size: 15px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.85);
  transition: var(--transition);
  position: relative;
}

.navbar.scrolled .nav-links a {
  color: var(--text-light);
}

.nav-links a:hover {
  color: #fff;
}

.navbar.scrolled .nav-links a:hover {
  color: var(--primary);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  border-radius: 1px;
  transition: var(--transition);
}

.nav-links a:hover::after {
  width: 100%;
}

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

.menu-toggle span {
  width: 24px;
  height: 2px;
  background: var(--bg);
  border-radius: 2px;
  transition: var(--transition);
}

.navbar.scrolled .menu-toggle span {
  background: var(--text);
}

/* ===== Hero ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 50%, #1a1a2e 100%);
  z-index: 0;
}

.hero-bg::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -30%;
  width: 80%;
  height: 200%;
  background: radial-gradient(ellipse, rgba(37, 99, 235, 0.15) 0%, transparent 60%);
  animation: heroGlow 8s ease-in-out infinite alternate;
}

.hero-bg::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -20%;
  width: 60%;
  height: 140%;
  background: radial-gradient(ellipse, rgba(6, 182, 212, 0.1) 0%, transparent 60%);
  animation: heroGlow 10s ease-in-out infinite alternate-reverse;
}

@keyframes heroGlow {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(30px, -20px) scale(1.05); }
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 120px 0 80px;
}

.hero-title {
  font-size: clamp(36px, 6vw, 68px);
  font-weight: 800;
  color: #fff;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
}

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

.hero-subtitle {
  font-size: clamp(16px, 2vw, 22px);
  color: rgba(255, 255, 255, 0.65);
  max-width: 600px;
  margin: 0 auto 40px;
  font-weight: 400;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 60px;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 60px;
}

.stat-item {
  text-align: center;
  color: #fff;
}

.stat-number {
  font-size: 42px;
  font-weight: 800;
  display: block;
  line-height: 1.2;
  background: linear-gradient(135deg, #fff, rgba(255, 255, 255, 0.7));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-label {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.5);
  font-weight: 500;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  cursor: pointer;
  border: none;
  transition: var(--transition);
  font-family: inherit;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.45);
}

.btn-outline {
  background: transparent;
  color: #fff;
  border: 1.5px solid rgba(255, 255, 255, 0.3);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.5);
}

.btn-block {
  width: 100%;
}

/* ===== Scroll Indicator ===== */
.scroll-indicator {
  position: absolute;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 1;
}

.scroll-indicator span {
  display: block;
  width: 24px;
  height: 24px;
  border-bottom: 2px solid rgba(255, 255, 255, 0.3);
  border-right: 2px solid rgba(255, 255, 255, 0.3);
  transform: rotate(45deg);
  animation: scrollBounce 2s infinite;
}

@keyframes scrollBounce {
  0%, 100% { transform: rotate(45deg) translateY(0); opacity: 0.3; }
  50% { transform: rotate(45deg) translateY(8px); opacity: 0.8; }
}

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

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-tag {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--primary);
  background: rgba(37, 99, 235, 0.08);
  padding: 6px 16px;
  border-radius: 20px;
  margin-bottom: 16px;
  letter-spacing: 0.5px;
}

.section-title {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  color: var(--text);
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}

.section-desc {
  font-size: 17px;
  color: var(--text-light);
  max-width: 500px;
  margin: 0 auto;
}

/* ===== About ===== */
.about {
  background: var(--bg-light);
}

.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 60px;
  align-items: center;
}

.about-content p {
  font-size: 16px;
  color: var(--text-light);
  margin-bottom: 20px;
  line-height: 1.8;
}

.about-highlights {
  margin-top: 32px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.highlight-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.highlight-icon {
  width: 44px;
  height: 44px;
  min-width: 44px;
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.1), rgba(6, 182, 212, 0.1));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
}

.highlight-icon svg {
  width: 22px;
  height: 22px;
}

.highlight-item h4 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 4px;
}

.highlight-item p {
  font-size: 14px;
  margin-bottom: 0;
  color: var(--text-lighter);
}

.about-visual {
  display: flex;
  justify-content: center;
}

.visual-card {
  position: relative;
  width: 320px;
  height: 380px;
  border-radius: 20px;
  overflow: hidden;
}

.visual-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #1e3a5f, #0f172a);
  border-radius: 20px;
}

.visual-bg::before {
  content: '';
  position: absolute;
  top: 20%;
  right: 10%;
  width: 200px;
  height: 200px;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.4), transparent 70%);
  border-radius: 50%;
}

.visual-bg::after {
  content: '';
  position: absolute;
  bottom: 10%;
  left: 20%;
  width: 150px;
  height: 150px;
  background: radial-gradient(circle, rgba(6, 182, 212, 0.3), transparent 70%);
  border-radius: 50%;
}

.visual-content {
  position: relative;
  z-index: 1;
  padding: 48px 36px;
  color: #fff;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  height: 100%;
}

.year-badge {
  display: inline-block;
  font-size: 72px;
  font-weight: 900;
  line-height: 1;
  background: linear-gradient(135deg, var(--primary-light), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 8px;
}

.visual-content h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 4px;
}

.visual-content p {
  color: rgba(255, 255, 255, 0.6);
  font-size: 15px;
}

/* ===== Services ===== */
.services {
  background: var(--bg);
}

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

.service-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 28px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.service-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transform: scaleX(0);
  transform-origin: left;
  transition: var(--transition);
}

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

.service-card:hover::before {
  transform: scaleX(1);
}

.service-icon {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.08), rgba(6, 182, 212, 0.08));
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  margin-bottom: 20px;
  transition: var(--transition);
}

.service-card:hover .service-icon {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
}

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

.service-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text);
}

.service-card p {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.7;
  margin-bottom: 20px;
}

.service-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.service-tags li {
  font-size: 12px;
  padding: 4px 12px;
  background: var(--bg-light);
  color: var(--text-light);
  border-radius: 20px;
  font-weight: 500;
}

/* ===== Advantages ===== */
.advantages {
  background: var(--bg-dark);
  color: #fff;
}

.advantages .section-title {
  color: #fff;
}

.advantages .section-desc {
  color: rgba(255, 255, 255, 0.5);
}

.advantages .section-tag {
  background: rgba(37, 99, 235, 0.15);
  color: var(--primary-light);
}

.advantages-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.advantage-card {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius);
  padding: 36px 28px;
  transition: var(--transition);
}

.advantage-card:hover {
  background: rgba(255, 255, 255, 0.08);
  transform: translateY(-4px);
}

.advantage-number {
  font-size: 48px;
  font-weight: 900;
  line-height: 1;
  background: linear-gradient(135deg, var(--primary-light), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 20px;
}

.advantage-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
}

.advantage-card p {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.5);
  line-height: 1.7;
}

/* ===== Contact ===== */
.contact {
  background: var(--bg-light);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.contact-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.contact-icon {
  width: 52px;
  height: 52px;
  min-width: 52px;
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.08), rgba(6, 182, 212, 0.08));
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
}

.contact-icon svg {
  width: 24px;
  height: 24px;
}

.contact-item h4 {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-lighter);
  margin-bottom: 4px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

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

.contact-item a {
  color: var(--primary);
  transition: var(--transition);
}

.contact-item a:hover {
  color: var(--primary-dark);
}

.contact-form {
  background: var(--bg);
  border-radius: var(--radius);
  padding: 36px;
  box-shadow: var(--shadow);
}

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

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 14px 16px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-family: inherit;
  color: var(--text);
  background: var(--bg);
  transition: var(--transition);
  outline: none;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--text-lighter);
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

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

/* ===== Footer ===== */
.footer {
  background: var(--bg-dark);
  color: rgba(255, 255, 255, 0.6);
  padding: 64px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

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

.footer-brand p {
  font-size: 14px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.4);
}

.footer-links h4,
.footer-contact h4 {
  color: #fff;
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 20px;
}

.footer-links ul {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-links a {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.4);
  transition: var(--transition);
}

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

.footer-contact p {
  font-size: 14px;
  margin-bottom: 8px;
  color: rgba(255, 255, 255, 0.4);
}

.footer-contact a {
  color: rgba(255, 255, 255, 0.4);
  transition: var(--transition);
}

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

.footer-bottom {
  padding: 24px 0;
  text-align: center;
}

.footer-bottom p {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.3);
}

/* ===== Back to Top ===== */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: var(--transition);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
  z-index: 100;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
}

.back-to-top svg {
  width: 20px;
  height: 20px;
}

/* ===== Animations ===== */
.fade-up {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

.fade-up.delay-1 { transition-delay: 0.15s; }
.fade-up.delay-2 { transition-delay: 0.3s; }
.fade-up.delay-3 { transition-delay: 0.45s; }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .advantages-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
}

@media (max-width: 768px) {
  .menu-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: 0;
    width: 280px;
    height: 100vh;
    background: var(--bg-dark);
    flex-direction: column;
    padding: 80px 32px 32px;
    gap: 24px;
    transform: translateX(100%);
    transition: var(--transition);
  }

  .nav-links.active {
    transform: translateX(0);
  }

  .nav-links a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 18px;
  }

  .nav-links a:hover {
    color: #fff;
  }

  .menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }

  .menu-toggle.active span:nth-child(2) {
    opacity: 0;
  }

  .menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .menu-toggle.active span {
    background: var(--bg) !important;
  }

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

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

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

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

  .hero-stats {
    gap: 32px;
  }

  .stat-number {
    font-size: 32px;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  section {
    padding: 72px 0;
  }

  .hero-content {
    padding: 100px 0 60px;
  }
}

@media (max-width: 480px) {
  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .hero-stats {
    flex-direction: column;
    gap: 20px;
  }

  .visual-card {
    width: 100%;
    height: 280px;
  }
}