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

:root {
  --bg: #fafafa;
  --bg-alt: #f0f4ff;
  --bg-card: #ffffff;
  --text-primary: #111827;
  --text-secondary: #4b5563;
  --text-muted: #9ca3af;
  --accent: #165dff;
  --accent-light: #eef4ff;
  --accent-gradient: linear-gradient(135deg, #165dff, #6366f1);
  --green: #059669;
  --green-light: #ecfdf5;
  --purple: #7c3aed;
  --purple-light: #f5f3ff;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.1);
  --radius: 12px;
  --radius-lg: 20px;
}

body {
  font-family:
    'Inter',
    -apple-system,
    BlinkMacSystemFont,
    'Segoe UI',
    Roboto,
    Oxygen,
    Ubuntu,
    Cantarell,
    sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.6;
}

.container {
  max-width: 1150px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== ANIMATIONS ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
@keyframes floatBlob {
  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }
  50% {
    transform: translate(-20px, 30px) scale(1.05);
  }
}
@keyframes floatBlob2 {
  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }
  50% {
    transform: translate(25px, -20px) scale(1.08);
  }
}
@keyframes ctaPulse {
  0%,
  100% {
    box-shadow: 0 4px 20px rgba(22, 93, 255, 0.3);
  }
  50% {
    box-shadow: 0 4px 36px rgba(22, 93, 255, 0.5);
  }
}
.animate-in {
  animation: fadeIn 0.8s ease both;
}
.delay-1 {
  animation-delay: 0.1s;
}
.delay-2 {
  animation-delay: 0.2s;
}
.delay-3 {
  animation-delay: 0.3s;
}
.delay-4 {
  animation-delay: 0.4s;
}

/* ===== NAVIGATION ===== */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  height: 56px;
  display: flex;
  align-items: center;
}
.nav-inner {
  max-width: 1150px;
  width: 100%;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text-primary);
}
.nav-brand img {
  width: 28px;
  height: 28px;
}
.nav-brand span {
  font-weight: 600;
  font-size: 1.05em;
}
.nav-cta {
  display: inline-block;
  padding: 8px 22px;
  background: var(--accent-gradient);
  color: #fff;
  font-size: 0.9em;
  font-weight: 600;
  border-radius: 9999px;
  text-decoration: none;
  transition:
    transform 0.25s ease,
    box-shadow 0.25s ease;
  box-shadow: 0 4px 16px rgba(22, 93, 255, 0.25);
}
.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(22, 93, 255, 0.35);
}
.nav-link {
  display: inline-block;
  padding: 8px 18px;
  color: var(--text-secondary);
  font-size: 0.9em;
  font-weight: 500;
  text-decoration: none;
  border-radius: 6px;
  transition:
    color 0.2s ease,
    background 0.2s ease;
}
.nav-link:hover {
  color: var(--accent);
  background: var(--accent-light);
}

/* ===== HERO ===== */
.hero {
  position: relative;
  overflow: hidden;
  text-align: center;
  padding: 70px 24px 90px;
  background: linear-gradient(180deg, #ffffff 0%, #f0f4ff 100%);
}
.hero::before {
  content: '';
  position: absolute;
  top: -120px;
  right: -100px;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.12) 0%, transparent 70%);
  border-radius: 50%;
  animation: floatBlob 12s ease-in-out infinite;
  pointer-events: none;
}
.hero::after {
  content: '';
  position: absolute;
  bottom: -80px;
  left: -80px;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(22, 93, 255, 0.08) 0%, transparent 70%);
  border-radius: 50%;
  animation: floatBlob2 15s ease-in-out infinite;
  pointer-events: none;
}

.hero-logo {
  width: 80px;
  height: 80px;
  margin-bottom: 28px;
  filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.08));
  position: relative;
  z-index: 1;
}
.hero h1 {
  font-size: 3em;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--text-primary);
  position: relative;
  z-index: 1;
}
.hero .subtitle {
  font-size: 1.15em;
  color: var(--text-secondary);
  max-width: 650px;
  margin: 16px auto 32px;
  line-height: 1.65;
  position: relative;
  z-index: 1;
}
.hero .cta-btn {
  display: inline-block;
  padding: 14px 36px;
  background: var(--accent-gradient);
  color: #fff;
  font-size: 1.05em;
  font-weight: 600;
  border-radius: 9999px;
  border: 2px solid transparent;
  text-decoration: none;
  transition:
    transform 0.25s ease,
    box-shadow 0.25s ease;
  box-shadow: 0 4px 20px rgba(22, 93, 255, 0.3);
  animation: ctaPulse 2.5s ease-in-out infinite;
  will-change: box-shadow;
  position: relative;
  z-index: 1;
}
.hero .cta-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 30px rgba(22, 93, 255, 0.4);
}
.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  position: relative;
  z-index: 1;
}
.cta-secondary {
  display: inline-block;
  padding: 14px 36px;
  background: transparent;
  color: var(--accent);
  font-size: 1.05em;
  font-weight: 600;
  border-radius: 9999px;
  text-decoration: none;
  border: 2px solid var(--accent);
  transition:
    transform 0.25s ease,
    background 0.25s ease,
    box-shadow 0.25s ease;
  position: relative;
  z-index: 1;
}
.cta-secondary:hover {
  transform: translateY(-3px);
  background: var(--accent-light);
  box-shadow: 0 8px 30px rgba(22, 93, 255, 0.15);
}

/* ===== SECTIONS (shared) ===== */
.section {
  padding: 72px 0;
}
.section-alt {
  background: var(--bg-alt);
}
.section-white {
  background: #fff;
}

.section-heading {
  text-align: center;
  font-size: 2em;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
  color: var(--text-primary);
}
.section-heading::after {
  content: '';
  display: block;
  width: 60px;
  height: 3px;
  background: var(--accent-gradient);
  border-radius: 2px;
  margin: 12px auto 0;
}
.section-sub {
  text-align: center;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 48px;
  font-size: 1.05em;
}

/* Section dividers */
.section-divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(22, 93, 255, 0.12), transparent);
  border: none;
  margin: 0;
}

/* ===== ABOUT ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 60px;
  align-items: start;
}
.about-text h2 {
  font-size: 2em;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
}
.about-text p {
  color: var(--text-secondary);
  margin-bottom: 18px;
  line-height: 1.7;
}
/* ===== FEATURES ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}
.feature-card {
  background: var(--bg-card);
  border-radius: 16px;
  padding: 28px;
  box-shadow: var(--shadow-md);
  border: 1px solid rgba(0, 0, 0, 0.04);
  transition:
    transform 0.3s ease,
    box-shadow 0.3s ease;
  border-top: 3px solid transparent;
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.feature-card .icon {
  font-size: 2em;
  margin-bottom: 14px;
  display: block;
}
.feature-card h3 {
  font-size: 1.1em;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--text-primary);
}
.feature-card p {
  font-size: 0.95em;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ===== CODE EXAMPLE ===== */
.code-block-wrap {
  background: #1e1e2e;
  border-radius: var(--radius);
  padding: 24px;
  overflow-x: auto;
  box-shadow:
    0 8px 32px rgba(0, 0, 0, 0.12),
    0 0 0 1px rgba(255, 255, 255, 0.04);
}
.code-block-wrap pre {
  margin: 0;
  font-family: 'JetBrains Mono', 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  font-size: 14px;
  line-height: 1.7;
  color: #cdd6f4;
}
.code-block-wrap pre .kw {
  color: #cba6f7;
}
.code-block-wrap pre .str {
  color: #a6e3a1;
}
.code-block-wrap pre .cmt {
  color: #6c7086;
}
.code-block-wrap pre .num {
  color: #fab387;
}
.code-block-wrap pre .fn {
  color: #89b4fa;
}
.code-block-wrap pre .unit {
  color: #f9e2af;
}
.code-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: start;
}

/* ===== STEPS ===== */
.steps {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0;
  position: relative;
  max-width: 1000px;
  margin: 0 auto;
}
.step-item {
  flex: 1 1 160px;
  max-width: 180px;
  text-align: center;
  position: relative;
  padding: 0 8px 40px;
}
.step-item::after {
  content: '';
  position: absolute;
  top: 20px;
  left: 60%;
  width: 80%;
  height: 2px;
  border-top: 2px dashed #d1d5db;
  pointer-events: none;
}
.step-item:last-child::after {
  display: none;
}
.step-number {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--accent-gradient);
  color: #fff;
  font-size: 0.95em;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 14px;
  box-shadow: 0 4px 12px rgba(22, 93, 255, 0.25);
  position: relative;
  z-index: 1;
}
.step-item h4 {
  font-size: 0.95em;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-primary);
}
.step-item p {
  font-size: 0.85em;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* ===== FOOTER ===== */
.site-footer {
  background: #0f172a;
  padding: 32px 0;
}
.footer-inner {
  text-align: center;
}
.footer-beian {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0;
}
.footer-beian a {
  color: #94a3b8;
  text-decoration: none;
  font-size: 0.85em;
  transition: color 0.2s;
}
.footer-beian a:hover {
  color: #fff;
}
.footer-sep {
  color: #475569;
  margin: 0 8px;
  font-size: 0.85em;
}
.footer-gongan img {
  height: 14px;
  vertical-align: middle;
  margin-right: 3px;
}
.footer-copy {
  color: #475569;
  font-size: 0.8em;
  margin-top: 8px;
}

/* ===== SUPPORT SECTION ===== */
.support-grid {
  display: flex;
  justify-content: center;
  gap: 40px;
  flex-wrap: wrap;
  margin-top: 32px;
}
.support-card {
  background: var(--bg-card);
  border-radius: 16px;
  padding: 32px;
  box-shadow: var(--shadow-md);
  border: 1px solid rgba(0, 0, 0, 0.04);
  text-align: center;
  width: 260px;
  transition:
    transform 0.3s ease,
    box-shadow 0.3s ease;
}
.support-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.support-card .qr-image {
  width: 200px;
  height: 200px;
  border-radius: 12px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
}
.support-card .card-label {
  margin-top: 16px;
  color: var(--text-primary);
  font-weight: 600;
  font-size: 1em;
}
.support-card .card-desc {
  margin-top: 6px;
  color: var(--text-secondary);
  font-size: 0.85em;
}
.support-card .paypal-btn {
  display: inline-block;
  margin-top: 12px;
  padding: 8px 24px;
  background: linear-gradient(135deg, #165dff, #6366f1);
  color: #fff;
  border: none;
  border-radius: 9999px;
  font-size: 0.85em;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  box-shadow: 0 4px 20px rgba(22, 93, 255, 0.3);
  transition:
    transform 0.25s ease,
    box-shadow 0.25s ease;
}
.support-card .paypal-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(22, 93, 255, 0.4);
}
.support-card .paypal-logo {
  height: 20px;
  vertical-align: middle;
  margin-left: 6px;
}

/* ===== SHOWCASE VIDEO ===== */
.showcase {
  padding: 0 24px 60px;
  text-align: center;
  background: linear-gradient(180deg, #f0f4ff 0%, #ffffff 100%);
}
.showcase video {
  max-width: 1000px;
  width: 100%;
  border-radius: 16px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  display: block;
  margin: 0 auto;
  background: #000;
}

/* ===== SCROLLBAR ===== */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: #d1d5db;
  border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
  background: #9ca3af;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .hero {
    padding: 50px 20px 70px;
  }
  .hero h1 {
    font-size: 2.2em;
  }
  .hero .subtitle {
    font-size: 1em;
  }
  .section {
    padding: 56px 0;
  }
  .section-heading {
    font-size: 1.7em;
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .code-grid {
    grid-template-columns: 1fr;
  }
  .step-item {
    flex: 1 1 140px;
    max-width: 160px;
  }
  .step-item::after {
    width: 60%;
    left: 60%;
  }
}
@media (max-width: 480px) {
  .hero h1 {
    font-size: 1.8em;
  }
  .hero .subtitle {
    font-size: 0.95em;
  }
  .hero .cta-btn {
    padding: 12px 28px;
    font-size: 0.95em;
  }
  .hero-actions .cta-secondary {
    padding: 12px 28px;
    font-size: 0.95em;
  }
  .section-heading {
    font-size: 1.4em;
  }
  .about-text h2 {
    font-size: 1.5em;
  }
  .step-item {
    flex: 1 1 100%;
    max-width: 260px;
  }
  .step-item::after {
    display: none;
  }
}