/* Landing Page Styles */

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: #000;
  min-height: 100vh;
  color: white;
  overflow-x: hidden;
}

/* Video background */
#video-background {
  position: fixed;
  top: 50%;
  left: 50%;
  min-width: 100%;
  min-height: 100%;
  width: auto;
  height: auto;
  transform: translate(-50%, -50%);
  z-index: 0;
  object-fit: cover;
}

/* Overlay để làm tối video */
.video-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.3);
  z-index: 1;
}

.container {
  position: relative;
  z-index: 2;
  max-width: 1200px;
  margin: 0 auto;
  padding: 3rem 2rem;
}

header {
  text-align: center;
  margin-bottom: 4rem;
  animation: fadeInDown 1s ease;
}

h1 {
  font-size: 3.5rem;
  font-weight: 800;
  margin-bottom: 1rem;
  background: linear-gradient(135deg, #60a5fa 0%, #a78bfa 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  font-size: 1.3rem;
  opacity: 0.9;
  margin-bottom: 0.5rem;
}

#clock {
  font-size: 1.1rem;
  opacity: 0.7;
  font-family: 'Courier New', monospace;
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.project-card {
  background: rgba(255, 255, 255, 0.05);
  backdrop-filter: blur(10px);
  border-radius: 20px;
  padding: 2.5rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  transition: all 0.4s ease;
  text-decoration: none;
  color: white;
  display: block;
  position: relative;
  overflow: hidden;
  animation: fadeInUp 0.8s ease;
}

.project-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(96, 165, 250, 0.1) 0%, rgba(167, 139, 250, 0.1) 100%);
  opacity: 0;
  transition: opacity 0.4s ease;
}

.project-card:hover {
  transform: translateY(-10px);
  border-color: rgba(96, 165, 250, 0.5);
  box-shadow: 0 20px 60px rgba(96, 165, 250, 0.3);
}

.project-card:hover::before {
  opacity: 1;
}

.project-icon {
  font-size: 3rem;
  margin-bottom: 1rem;
  display: block;
}

.project-card h2 {
  font-size: 1.8rem;
  margin-bottom: 1rem;
  position: relative;
  z-index: 1;
}

.project-card p {
  opacity: 0.85;
  line-height: 1.6;
  position: relative;
  z-index: 1;
}

.project-card .tech-stack {
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.85rem;
  opacity: 0.7;
}

.d-none {
  display: none !important;
}

footer {
  text-align: center;
  margin-top: 5rem;
  padding: 2rem;
  opacity: 0.7;
  font-size: 0.9rem;
}

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

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

/* Animation delays cho staggered effect */
.project-card:nth-child(1) { animation-delay: 0.1s; }
.project-card:nth-child(2) { animation-delay: 0.2s; }
.project-card:nth-child(3) { animation-delay: 0.3s; }
.project-card:nth-child(4) { animation-delay: 0.4s; }

/* Responsive */
@media (max-width: 768px) {
  h1 {
    font-size: 2.5rem;
  }
  
  .projects-grid {
    grid-template-columns: 1fr;
  }
}