/* ===== CSS Variables & Theme System ===== */
:root, [data-theme="dark"] {
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-tertiary: #1a1a2e;
  --text-primary: #f0f0f5;
  --text-secondary: #8a8a9a;
  --text-muted: #5a5a7a;
  --border-color: rgba(255, 255, 255, 0.08);
  --accent: #7c3aed;
  --accent-hover: #6d28d9;
  --accent-light: rgba(124, 58, 237, 0.1);
  --gradient-start: #7c3aed;
  --gradient-end: #3b82f6;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.4);
  --card-bg: rgba(255, 255, 255, 0.03);
  --card-hover: rgba(255, 255, 255, 0.06);
}

[data-theme="light"] {
  --bg-primary: #fafafa;
  --bg-secondary: #ffffff;
  --bg-tertiary: #f5f5f7;
  --text-primary: #1a1a2e;
  --text-secondary: #5a5a7a;
  --text-muted: #8a8a9a;
  --border-color: rgba(0, 0, 0, 0.08);
  --accent: #7c3aed;
  --accent-hover: #6d28d9;
  --accent-light: rgba(124, 58, 237, 0.08);
  --gradient-start: #7c3aed;
  --gradient-end: #3b82f6;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.12);
  --card-bg: #ffffff;
  --card-hover: #f8f8fa;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  transition: background 0.4s ease, color 0.4s ease;
  overflow-x: hidden;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.3s ease;
}

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

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

/* ===== Container ===== */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

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

/* ===== Header & Navigation ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  transition: all 0.3s ease;
}

.header.scrolled {
  box-shadow: var(--shadow);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
}

.logo img {
  width: 40px;
  height: 40px;
  border-radius: 8px;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-link {
  color: var(--text-secondary);
  font-weight: 500;
  position: relative;
  transition: color 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
  color: var(--text-primary);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* Theme Toggle */
.theme-toggle {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 8px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  transition: all 0.3s ease;
  position: relative;
  color: var(--text-primary);
}

.theme-toggle:hover {
  background: var(--card-hover);
  transform: scale(1.05);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  transition: transform 0.4s ease, opacity 0.3s ease;
  position: absolute;
}

.theme-toggle .icon-sun {
  opacity: 0;
  transform: rotate(-90deg) scale(0.5);
}

.theme-toggle .icon-moon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

[data-theme="light"] .theme-toggle .icon-sun {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

[data-theme="light"] .theme-toggle .icon-moon {
  opacity: 0;
  transform: rotate(90deg) scale(0.5);
}

/* Mobile Menu */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 24px;
  cursor: pointer;
}

@media (max-width: 768px) {
  .nav-menu {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    flex-direction: column;
    padding: 24px;
    gap: 16px;
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: all 0.3s ease;
    border-bottom: 1px solid var(--border-color);
  }

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

  .mobile-menu-toggle {
    display: block;
  }
}

/* ===== Hero Section ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding-top: 72px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.5;
}

.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--bg-primary) 0%, transparent 50%, var(--bg-primary) 100%);
}

/* 浅色模式banner样式 */
[data-theme="light"] .hero-bg {
  background: #1a1a2e;
}

[data-theme="light"] .hero-bg img {
  opacity: 1;
  filter: brightness(0.5) contrast(1.4) saturate(1.2);
}

[data-theme="light"] .hero-bg::after {
  background: linear-gradient(135deg, 
    rgba(26, 26, 46, 0.2) 0%, 
    rgba(26, 26, 46, 0.05) 50%, 
    rgba(26, 26, 46, 0.2) 100%);
}

[data-theme="light"] .hero-title {
  color: #ffffff;
  -webkit-text-fill-color: #ffffff;
  background: none;
  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.6);
}

[data-theme="light"] .hero-subtitle {
  color: rgba(255, 255, 255, 0.95);
  text-shadow: 0 1px 10px rgba(0, 0, 0, 0.6);
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 900px;
  padding: 0 24px;
}

.hero-title {
  font-size: clamp(2.5rem, 5vw, 4.5rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 24px;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: fadeInUp 0.8s ease;
}

.hero-subtitle {
  font-size: clamp(1.125rem, 2vw, 1.5rem);
  color: var(--text-secondary);
  margin-bottom: 40px;
  animation: fadeInUp 0.8s ease 0.2s backwards;
  line-height: 1.6;
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease 0.4s backwards;
  margin-bottom: 60px;
}

/* ===== Hero Carousel (Homepage Only) ===== */
.hero.hero-carousel {
  position: relative;
}

.hero.hero-carousel .hero-carousel-wrapper {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero.hero-carousel .hero-slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 1s ease-in-out;
}

.hero.hero-carousel .hero-slide.active {
  opacity: 1;
}

.hero.hero-carousel .hero-slide-bg {
  position: absolute;
  inset: 0;
}

.hero.hero-carousel .hero-slide-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero.hero-carousel .hero-slide-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, 
    rgba(10, 10, 15, 0.85) 0%, 
    rgba(10, 10, 15, 0.6) 50%, 
    rgba(10, 10, 15, 0.85) 100%);
}

[data-theme="light"] .hero.hero-carousel .hero-slide-overlay {
  background: linear-gradient(135deg, 
    rgba(0, 0, 0, 0.6) 0%, 
    rgba(0, 0, 0, 0.4) 50%, 
    rgba(0, 0, 0, 0.6) 100%);
}

[data-theme="light"] .hero.hero-carousel .hero-slide-content .hero-title {
  color: #ffffff;
  -webkit-text-fill-color: #ffffff;
  background: none;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

[data-theme="light"] .hero.hero-carousel .hero-slide-content .hero-subtitle {
  color: rgba(255, 255, 255, 0.95);
  text-shadow: 0 1px 5px rgba(0, 0, 0, 0.3);
}

[data-theme="light"] .hero.hero-carousel .hero-slide-content .btn-secondary {
  background: rgba(255, 255, 255, 0.95);
  color: #1a1a2e;
  border-color: rgba(255, 255, 255, 0.95);
}

.hero.hero-carousel .hero-slide-content {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 0 24px;
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.hero.hero-carousel .hero-slide.active .hero-slide-content {
  opacity: 1;
  transform: translateY(0);
}

.hero.hero-carousel .hero-slide-content .hero-title {
  font-size: clamp(2.5rem, 5vw, 4.5rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 24px;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero.hero-carousel .hero-slide-content .hero-subtitle {
  font-size: clamp(1.125rem, 2vw, 1.5rem);
  color: var(--text-secondary);
  margin-bottom: 40px;
  line-height: 1.6;
  max-width: 700px;
}

.hero.hero-carousel .hero-slide-content .hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 0;
}

/* Animated particles */
.hero-particles {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 1;
}

.particle {
  position: absolute;
  width: 4px;
  height: 4px;
  background: var(--accent);
  border-radius: 50%;
  opacity: 0.3;
  animation: float 15s infinite;
}

.particle:nth-child(1) { left: 10%; animation-delay: 0s; animation-duration: 12s; }
.particle:nth-child(2) { left: 20%; animation-delay: 2s; animation-duration: 14s; }
.particle:nth-child(3) { left: 30%; animation-delay: 4s; animation-duration: 16s; }
.particle:nth-child(4) { left: 40%; animation-delay: 1s; animation-duration: 13s; }
.particle:nth-child(5) { left: 50%; animation-delay: 3s; animation-duration: 15s; }
.particle:nth-child(6) { left: 60%; animation-delay: 5s; animation-duration: 17s; }
.particle:nth-child(7) { left: 70%; animation-delay: 2.5s; animation-duration: 14s; }
.particle:nth-child(8) { left: 80%; animation-delay: 4.5s; animation-duration: 16s; }
.particle:nth-child(9) { left: 90%; animation-delay: 1.5s; animation-duration: 13s; }
.particle:nth-child(10) { left: 15%; animation-delay: 3.5s; animation-duration: 15s; }

@keyframes float {
  0%, 100% {
    transform: translateY(100vh) scale(0);
    opacity: 0;
  }
  10% {
    opacity: 0.3;
  }
  50% {
    transform: translateY(50vh) scale(1);
    opacity: 0.6;
  }
  90% {
    opacity: 0.3;
  }
}

/* Carousel indicators */
.hero-indicators {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 12px;
  z-index: 3;
}

.hero-indicator {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--border-color);
  cursor: pointer;
  transition: all 0.3s ease;
  border: 2px solid transparent;
}

.hero-indicator.active {
  background: var(--accent);
  border-color: var(--accent);
  transform: scale(1.2);
}

.hero-indicator:hover {
  background: var(--accent);
  opacity: 0.7;
}

/* Carousel controls */
.hero-controls {
  position: absolute;
  top: 50%;
  width: 100%;
  display: flex;
  justify-content: space-between;
  padding: 0 20px;
  transform: translateY(-50%);
  z-index: 3;
  pointer-events: none;
}

.hero-control {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.3s ease;
  pointer-events: all;
  color: var(--text-primary);
}

.hero-control:hover {
  background: var(--accent);
  color: white;
  transform: scale(1.1);
}

.hero-control svg {
  width: 24px;
  height: 24px;
}

@media (max-width: 768px) {
  .hero-controls {
    display: none;
  }
  
  .hero-indicators {
    bottom: 20px;
  }
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: 12px;
  font-weight: 600;
  font-size: 16px;
  cursor: pointer;
  transition: all 0.3s ease;
  border: none;
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  color: white;
  box-shadow: 0 4px 20px rgba(124, 58, 237, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 30px rgba(124, 58, 237, 0.4);
}

.btn-secondary {
  background: var(--card-bg);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background: var(--card-hover);
  transform: translateY(-2px);
}

/* ===== Section ===== */
.section {
  padding: 120px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 600px;
  margin: 0 auto 80px;
}

.section-title {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
}

/* ===== Cards ===== */
.card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  padding: 32px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--gradient-start), var(--gradient-end));
  transform: scaleX(0);
  transition: transform 0.3s ease;
}

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

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

.card-icon {
  width: 64px;
  height: 64px;
  border-radius: 16px;
  background: var(--accent-light);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  color: var(--accent);
}

.card-icon svg {
  width: 32px;
  height: 32px;
}

.card-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.card-text {
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ===== Grid Layouts ===== */
.grid {
  display: grid;
  gap: 32px;
}

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

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

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

@media (max-width: 1024px) {
  .grid-4 {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 768px) {
  .grid-3, .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
}

/* ===== About Section ===== */
.about-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.about-image {
  border-radius: 24px;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.about-image img {
  width: 100%;
  height: auto;
  transition: transform 0.4s ease;
}

.about-image:hover img {
  transform: scale(1.05);
}

.about-text h3 {
  font-size: 2rem;
  margin-bottom: 24px;
  color: var(--text-primary);
}

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

@media (max-width: 768px) {
  .about-content {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

/* ===== Services Section ===== */
.service-card {
  text-align: center;
}

.service-card img {
  width: 100%;
  height: 240px;
  object-fit: cover;
  border-radius: 16px;
  margin-bottom: 24px;
  transition: transform 0.3s ease;
}

.service-card:hover img {
  transform: scale(1.05);
}

/* ===== Cases Section ===== */
.case-card {
  position: relative;
  overflow: hidden;
  border-radius: 20px;
  cursor: pointer;
}

.case-card img {
  width: 100%;
  height: 300px;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.case-card:hover img {
  transform: scale(1.1);
}

.case-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.9) 0%, transparent 50%);
  display: flex;
  align-items: flex-end;
  padding: 32px;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.case-card:hover .case-overlay {
  opacity: 1;
}

.case-info h4 {
  color: white;
  font-size: 1.5rem;
  margin-bottom: 8px;
}

.case-info p {
  color: rgba(255, 255, 255, 0.8);
}

/* ===== Contact Section ===== */
.contact-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

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

.contact-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: var(--accent-light);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
  flex-shrink: 0;
}

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

.contact-details h4 {
  font-size: 1.125rem;
  margin-bottom: 4px;
  color: var(--text-primary);
}

.contact-details p {
  color: var(--text-secondary);
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.form-label {
  font-weight: 500;
  color: var(--text-primary);
}

.form-input,
.form-textarea {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 14px 16px;
  color: var(--text-primary);
  font-family: inherit;
  font-size: 16px;
  transition: all 0.3s ease;
}

.form-input:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}

.form-textarea {
  resize: vertical;
  min-height: 120px;
}

@media (max-width: 768px) {
  .contact-content {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

/* ===== Footer ===== */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 64px 0 32px;
}

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

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.footer-brand .logo {
  margin-bottom: 8px;
}

.footer-brand p {
  color: var(--text-secondary);
  line-height: 1.7;
}

.footer-section h4 {
  font-size: 1.125rem;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-links a {
  color: var(--text-secondary);
  transition: color 0.3s ease;
}

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

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

.footer-bottom p {
  margin: 4px 0;
  font-size: 14px;
}

.footer-icp a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.3s;
}

.footer-icp a:hover {
  color: var(--accent);
}

@media (max-width: 768px) {
  .footer-content {
    grid-template-columns: 1fr;
    gap: 32px;
  }
}

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

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

.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.animate-on-scroll.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Loading States ===== */
.loading {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid var(--border-color);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* ===== Utility Classes ===== */
.text-center {
  text-align: center;
}

.mt-4 {
  margin-top: 32px;
}

.mb-4 {
  margin-bottom: 32px;
}

.hidden {
  display: none;
}