/* ============================================
   Cloud Dream - Stripe-inspired Homepage
   ============================================ */

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

:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f6f9fc;
  --color-bg-dark: #0a2540;
  --color-text: #1a1a2e;
  --color-text-secondary: #425466;
  --color-text-light: #8892a0;
  --color-primary: #635bff;
  --color-primary-dark: #4b45c6;
  --color-primary-light: #7a73ff;
  --color-accent: #00d4aa;
  --color-accent-dark: #00b894;
  --color-border: #e3e8ee;
  --color-white: #ffffff;
  --gradient-hero: linear-gradient(135deg, #0a2540 0%, #1a3a5c 30%, #2d4a6f 60%, #0a2540 100%);
  --gradient-cta: linear-gradient(135deg, #635bff 0%, #00d4aa 100%);
  --gradient-card: linear-gradient(180deg, rgba(99, 91, 255, 0.03) 0%, rgba(0, 212, 170, 0.03) 100%);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.12);
  --shadow-xl: 0 20px 60px rgba(0, 0, 0, 0.15);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
}

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

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  font-size: 16px;
  overflow-x: hidden;
}

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

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

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

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 500;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-white);
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(99, 91, 255, 0.35);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.12);
  color: var(--color-white);
  border: 1px solid rgba(255, 255, 255, 0.25);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.2);
}

.btn-ghost {
  background: transparent;
  color: var(--color-text-secondary);
  padding: 8px 16px;
}

.btn-ghost:hover {
  color: var(--color-primary);
}

.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border: 1.5px solid var(--color-primary);
}

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

.btn-large {
  padding: 16px 36px;
  font-size: 17px;
  border-radius: var(--radius-md);
}

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: all var(--transition);
}

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

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

.logo-img {
  height: 36px;
  width: auto;
}

.logo-text {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-text);
}

.nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  font-size: 15px;
  color: var(--color-text-secondary);
  transition: color var(--transition);
  position: relative;
}

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

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-primary);
  border-radius: 1px;
}

.nav-dropdown {
  position: relative;
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background: var(--color-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  padding: 8px;
  min-width: 180px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: all var(--transition);
}

.nav-dropdown:hover .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-item {
  display: block;
  padding: 10px 14px;
  font-size: 14px;
  color: var(--color-text-secondary);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.dropdown-item:hover {
  background: var(--color-bg-alt);
  color: var(--color-primary);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  border-radius: 1px;
  transition: all var(--transition);
}

/* Hero Section */
.hero {
  position: relative;
  padding: 160px 0 100px;
  overflow: hidden;
  background: var(--color-bg-dark);
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: var(--gradient-hero);
  z-index: 0;
}

.hero-bg::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(99, 91, 255, 0.25) 0%, transparent 70%);
  border-radius: 50%;
}

.hero-bg::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(0, 212, 170, 0.15) 0%, transparent 70%);
  border-radius: 50%;
}

.hero-inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero-content {
  color: var(--color-white);
}

.hero-title {
  font-size: clamp(32px, 5vw, 52px);
  font-weight: 700;
  line-height: 1.15;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}

.hero-subtitle {
  font-size: 18px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.75);
  margin-bottom: 36px;
  max-width: 520px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}

.hero-graphic {
  position: relative;
  width: 100%;
  max-width: 420px;
  aspect-ratio: 1;
}

.graphic-card {
  position: absolute;
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(16px);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-lg);
  padding: 20px 24px;
  display: flex;
  align-items: center;
  gap: 14px;
  color: var(--color-white);
  font-size: 15px;
  font-weight: 500;
  animation: float 6s ease-in-out infinite;
}

.graphic-card-1 {
  top: 10%;
  left: 5%;
  animation-delay: 0s;
}

.graphic-card-2 {
  top: 45%;
  right: 0;
  animation-delay: 2s;
}

.graphic-card-3 {
  bottom: 15%;
  left: 15%;
  animation-delay: 4s;
}

.graphic-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(99, 91, 255, 0.2);
  border-radius: var(--radius-sm);
}

.graphic-icon svg {
  width: 22px;
  height: 22px;
  stroke: var(--color-accent);
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

/* Stats Section */
.stats {
  background: var(--color-white);
  padding: 0;
  position: relative;
  z-index: 2;
  margin-top: -40px;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: var(--color-white);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  overflow: hidden;
}

.stat-item {
  padding: 40px 24px;
  text-align: center;
  border-right: 1px solid var(--color-border);
  transition: all var(--transition);
}

.stat-item:last-child {
  border-right: none;
}

.stat-item:hover {
  background: var(--gradient-card);
}

.stat-number {
  font-size: 36px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 8px;
  letter-spacing: -0.02em;
}

.stat-label {
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* Section Common */
.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 60px;
}

.section-tag {
  display: inline-block;
  padding: 6px 16px;
  background: linear-gradient(135deg, rgba(99, 91, 255, 0.08), rgba(0, 212, 170, 0.08));
  color: var(--color-primary);
  font-size: 13px;
  font-weight: 600;
  border-radius: 100px;
  margin-bottom: 16px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.section-title {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
  color: var(--color-text);
}

.section-desc {
  font-size: 17px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* About Section */
.about {
  padding: 100px 0;
  background: var(--color-bg-alt);
}

.about-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

.about-card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  transition: all var(--transition);
  border: 1px solid transparent;
}

.about-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(99, 91, 255, 0.15);
}

.about-card-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(99, 91, 255, 0.1), rgba(0, 212, 170, 0.1));
  border-radius: var(--radius-md);
  margin-bottom: 20px;
}

.about-card-icon svg {
  width: 24px;
  height: 24px;
  stroke: var(--color-primary);
}

.about-card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
}

.about-card p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

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

/* Why Choose Section */
.why-choose {
  padding: 100px 0;
  background: var(--color-white);
}

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

.feature-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: all var(--transition);
}

.feature-card:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.feature-icon {
  width: 52px;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  border-radius: var(--radius-md);
  margin-bottom: 24px;
}

.feature-icon svg {
  width: 26px;
  height: 26px;
  stroke: var(--color-white);
}

.feature-card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
}

.feature-card p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.65;
}

/* Capabilities Section */
.capabilities {
  padding: 100px 0;
  background: var(--color-bg-alt);
}

.capabilities-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.capabilities-content .section-tag {
  margin-bottom: 16px;
}

.capabilities-content .section-title {
  text-align: left;
  margin-bottom: 12px;
}

.capabilities-content .section-desc {
  text-align: left;
  margin-bottom: 40px;
}

.capability-list {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.capability-item {
  display: flex;
  gap: 20px;
  align-items: flex-start;
}

.capability-badge {
  flex-shrink: 0;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary);
  color: var(--color-white);
  font-size: 16px;
  font-weight: 700;
  border-radius: var(--radius-md);
}

.capability-item h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--color-text);
}

.capability-item p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.capabilities-visual {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
}

.capabilities-img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

/* Partners Section */
.partners {
  padding: 100px 0;
  background: var(--color-white);
}

.partners-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}

.partner-card {
  background: var(--color-bg-alt);
  border-radius: var(--radius-lg);
  padding: 40px 36px;
  transition: all var(--transition);
  border: 1px solid transparent;
}

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

.partner-logo {
  height: 48px;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
}

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

.partner-card h3 {
  font-size: 22px;
  font-weight: 600;
  margin-bottom: 14px;
  color: var(--color-text);
}

.partner-card p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* CTA Section */
.cta {
  position: relative;
  padding: 100px 0;
  overflow: hidden;
  background: var(--color-bg-dark);
}

.cta-bg {
  position: absolute;
  inset: 0;
  background: var(--gradient-hero);
}

.cta-bg::before {
  content: '';
  position: absolute;
  top: -40%;
  left: 50%;
  transform: translateX(-50%);
  width: 1000px;
  height: 600px;
  background: radial-gradient(ellipse, rgba(99, 91, 255, 0.3) 0%, transparent 70%);
}

.cta-inner {
  position: relative;
  z-index: 1;
  text-align: center;
  color: var(--color-white);
}

.cta-title {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.cta-desc {
  font-size: 18px;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 36px;
}

/* Footer */
.footer {
  background: #0a1929;
  color: rgba(255, 255, 255, 0.6);
  padding: 60px 0 40px;
}

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

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

.footer-brand .logo-text {
  color: var(--color-white);
}

.footer-brand-desc {
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 24px;
  max-width: 280px;
}

.footer-qr img {
  width: 100px;
  height: 100px;
  border-radius: var(--radius-sm);
  background: var(--color-white);
  padding: 6px;
}

.footer-links h4 {
  color: var(--color-white);
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 20px;
}

.footer-links a {
  display: block;
  font-size: 14px;
  margin-bottom: 12px;
  transition: color var(--transition);
}

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

.footer-bottom {
  padding-top: 32px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13px;
}

.footer-bottom a {
  color: rgba(255, 255, 255, 0.5);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.footer-bottom a:hover {
  color: var(--color-white);
}

/* Mobile Responsive */
@media (max-width: 1024px) {
  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-subtitle {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-actions {
    justify-content: center;
  }

  .hero-visual {
    display: none;
  }

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

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

  .capabilities-inner {
    grid-template-columns: 1fr;
  }

  .capabilities-visual {
    order: -1;
  }

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

@media (max-width: 768px) {
  .nav {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--color-white);
    flex-direction: column;
    padding: 24px;
    gap: 20px;
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-lg);
    transform: translateY(-120%);
    opacity: 0;
    transition: all var(--transition);
    z-index: 999;
  }

  .nav.open {
    transform: translateY(0);
    opacity: 1;
  }

  .nav-toggle {
    display: flex;
  }

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

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

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

  .header-actions .btn-ghost {
    display: none;
  }

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

  .stat-item {
    padding: 28px 16px;
  }

  .stat-item:nth-child(2) {
    border-right: none;
  }

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

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

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

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

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

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }

  .hero {
    padding: 130px 0 80px;
  }

  .section-header {
    margin-bottom: 40px;
  }

  .about,
  .why-choose,
  .capabilities,
  .partners,
  .cta {
    padding: 70px 0;
  }
}

@media (max-width: 480px) {
  .stats-grid {
    grid-template-columns: 1fr;
  }

  .stat-item {
    border-right: none;
    border-bottom: 1px solid var(--color-border);
  }

  .stat-item:last-child {
    border-bottom: none;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .hero-actions .btn {
    width: 100%;
    max-width: 280px;
  }

  .about-actions {
    flex-direction: column;
    align-items: center;
  }

  .about-actions .btn {
    width: 100%;
    max-width: 280px;
  }
}

/* Animations */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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