:root {
  --bg-dark: #12101a;
  --bg-card: #1f1b2e;
  --bg-card-hover: #2a243e;
  --text-main: #f2f0f7;
  --text-muted: #a59fb5;
  --accent-pink: #ff5b9a;
  --accent-purple: #9d4edd;
  --accent-blue: #00d2ff;
  --accent-yellow: #ffde00;
  --glass-bg: rgba(31, 27, 46, 0.7);
  --glass-border: rgba(255, 255, 255, 0.1);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.6;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 15% 10%, rgba(157, 78, 221, 0.15) 0%, transparent 40%),
    radial-gradient(circle at 85% 90%, rgba(0, 210, 255, 0.15) 0%, transparent 40%);
  background-attachment: fixed;
}

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

ul {
  list-style: none;
}

/* Header */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: 15px 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 1000;
  transition: all 0.3s ease;
}

.site-header.scrolled {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--glass-border);
  padding: 10px 30px;
}

.header-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.2rem;
  letter-spacing: 1px;
  background: linear-gradient(90deg, var(--accent-pink), var(--accent-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.header-logo img {
  height: 32px;
  border-radius: 8px;
}

.header-nav {
  display: flex;
  gap: 25px;
}

.header-nav a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-main);
  transition: color 0.2s;
  position: relative;
}

.header-nav a:hover {
  color: var(--accent-pink);
}

.header-nav a::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-pink);
  transition: width 0.3s;
}

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

/* Hero Section */
.hero-section {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 100px 20px 60px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.4;
  filter: blur(2px);
}

.hero-bg::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 50%;
  background: linear-gradient(to top, var(--bg-dark), transparent);
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 800px;
  animation: fadeUp 1s ease-out;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 20px;
  background: linear-gradient(135deg, #fff, var(--accent-pink), var(--accent-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  text-shadow: 0 4px 20px rgba(255, 91, 154, 0.3);
}

.hero-desc {
  font-size: 1.2rem;
  color: var(--text-main);
  margin-bottom: 40px;
  text-shadow: 0 2px 10px rgba(0,0,0,0.5);
}

.btn-download {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 15px 40px;
  font-size: 1.1rem;
  font-weight: 700;
  color: #fff;
  background: linear-gradient(45deg, var(--accent-pink), var(--accent-purple));
  border-radius: 30px;
  box-shadow: 0 4px 15px rgba(157, 78, 221, 0.4);
  transition: transform 0.3s, box-shadow 0.3s;
  border: none;
  cursor: pointer;
}

.btn-download:hover {
  transform: translateY(-3px) scale(1.05);
  box-shadow: 0 8px 25px rgba(255, 91, 154, 0.6);
}

/* Common Section */
.section {
  padding: 80px 20px;
  max-width: 1200px;
  margin: 0 auto;
}

.section-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 15px;
  text-align: center;
}

.section-subtitle {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 50px;
  font-size: 1.05rem;
}

/* Features / Advantages */
.features-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

.feature-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 30px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: transform 0.3s, background 0.3s;
}

.feature-card:hover {
  transform: translateY(-5px);
  background: var(--bg-card-hover);
}

.feature-icon {
  width: 50px;
  height: 50px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: bold;
  margin-bottom: 20px;
}

.icon-pink { background: rgba(255, 91, 154, 0.2); color: var(--accent-pink); }
.icon-blue { background: rgba(0, 210, 255, 0.2); color: var(--accent-blue); }
.icon-purple { background: rgba(157, 78, 221, 0.2); color: var(--accent-purple); }
.icon-yellow { background: rgba(255, 222, 0, 0.2); color: var(--accent-yellow); }

.feature-card h3 {
  font-size: 1.3rem;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Interface Showcase */
.showcase-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
  align-items: center;
}

.showcase-text h2 {
  font-size: 1.8rem;
  margin-bottom: 20px;
  color: var(--accent-blue);
}

.showcase-text p {
  color: var(--text-muted);
  margin-bottom: 15px;
  font-size: 1rem;
}

.showcase-images {
  display: flex;
  gap: 15px;
  overflow-x: auto;
  padding-bottom: 20px;
  scrollbar-width: thin;
}

.showcase-images::-webkit-scrollbar {
  height: 6px;
}
.showcase-images::-webkit-scrollbar-thumb {
  background: var(--accent-purple);
  border-radius: 4px;
}

.mockup {
  flex: 0 0 auto;
  width: 240px;
  border-radius: 20px;
  overflow: hidden;
  border: 4px solid #333;
  box-shadow: 0 10px 20px rgba(0,0,0,0.5);
  transition: transform 0.3s;
}

.mockup:hover {
  transform: scale(1.05);
}

.mockup img {
  width: 100%;
  height: auto;
  display: block;
}

/* Gallery / Image Wall */
.wall-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 15px;
}

.wall-item {
  border-radius: 12px;
  overflow: hidden;
  position: relative;
  aspect-ratio: 3/4;
}

.wall-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s;
}

.wall-item:hover img {
  transform: scale(1.1);
}

.wall-item.wide {
  grid-column: span 2;
  aspect-ratio: 16/9;
}

/* Footer */
.site-footer {
  margin-top: 60px;
  padding: 40px 20px;
  border-top: 1px solid var(--glass-border);
  text-align: center;
  color: var(--text-muted);
  font-size: 0.85rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

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

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

.footer-info {
  margin-bottom: 10px;
}

.footer-info a {
  color: var(--text-muted);
  transition: color 0.3s;
}

.footer-info a:hover {
  color: var(--text-main);
}

.update-time {
  margin-bottom: 20px;
}

/* Animations */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.reveal {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal.active {
  /* Kept visible, animation handled via class */
}

/* Responsive */
@media (min-width: 768px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .showcase-grid {
    grid-template-columns: 1fr 1fr;
  }
  .showcase-images {
    flex-wrap: wrap;
    justify-content: center;
  }
  .mockup {
    width: calc(50% - 10px);
    max-width: 260px;
  }
  .wall-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .wall-item.wide {
    grid-column: span 3;
  }
}

@media (min-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(4, 1fr);
  }
  .wall-grid {
    grid-template-columns: repeat(4, 1fr);
  }
  .wall-item.wide {
    grid-column: span 2;
    aspect-ratio: 16/9;
  }
  .hero-title {
    font-size: 4.5rem;
  }
  .header-nav {
    gap: 40px;
  }
}