:root {
  --primary: #0064e0;
  --primary-hover: #0054c2;
  --text-main: #1c2b33;
  --text-secondary: #65676b;
  --bg-color: #ffffff;
  --bg-gray: #f5f6f6;
  --bg-dark: #111418;
  --border-radius-lg: 40px;
  --border-radius-md: 24px;
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-family);
  color: var(--text-main);
  background-color: var(--bg-color);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

/* Sticky Header */
header {
  position: fixed; top: 0; left: 0; right: 0;
  height: 80px;
  background-color: transparent;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 40px;
  z-index: 1000;
  transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

header.scrolled {
  height: 80px;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 2px 20px rgba(0,0,0,0.06);
}

.logo-img { height: 64px; transition: height 0.4s; }
header.scrolled .logo-img { height: 52px; }

.nav-links { display: flex; gap: 32px; }
.nav-links a {
  font-size: 16px; font-weight: 500; color: #fff;
  transition: color 0.3s;
}
header.scrolled .nav-links a { color: var(--text-main); }
.nav-links a:hover { color: rgba(255,255,255,0.7); }
header.scrolled .nav-links a:hover { color: var(--primary); }

.cta-nav {
  background-color: #fff; color: var(--text-main);
  padding: 12px 24px; border-radius: 40px;
  font-weight: 600; font-size: 15px;
  transition: background-color 0.3s, transform 0.3s;
}
header.scrolled .cta-nav {
  background-color: #e4e6eb;
}
.cta-nav:hover { transform: scale(1.05); }

/* Buttons */
.primary-btn {
  background-color: var(--primary); color: white;
  padding: 16px 36px; border-radius: 50px;
  font-weight: 600; font-size: 18px; display: inline-block;
  transition: transform 0.3s ease, background-color 0.3s;
  border: none; cursor: pointer;
}
.primary-btn:hover { background-color: var(--primary-hover); transform: scale(1.05); }

.secondary-btn {
  background-color: #fff; color: var(--text-main);
  padding: 16px 36px; border-radius: 50px;
  font-weight: 600; font-size: 18px; display: inline-block;
  transition: transform 0.3s ease;
}
.secondary-btn:hover { transform: scale(1.05); }

/* Hero Section */
.hero {
  position: relative; height: 100vh; min-height: 800px;
  display: flex; flex-direction: column; justify-content: flex-end;
  padding: 100px 80px; overflow: hidden;
}
.hero-video-bg {
  position: absolute; top: 0; left: 0; width: 100%; height: 100%;
  object-fit: cover; z-index: -2;
  transform: scale(1);
  transition: transform 0.1s linear;
}
.hero-overlay {
  position: absolute; top: 0; left: 0; width: 100%; height: 100%;
  background: linear-gradient(0deg, rgba(0,0,0,0.6) 0%, rgba(0,0,0,0.1) 60%, rgba(0,0,0,0.4) 100%);
  z-index: -1;
}
.hero-content {
  position: relative; z-index: 10; color: #fff;
  max-width: 1000px; padding-bottom: 60px;
}
.hero h1 {
  font-size: clamp(60px, 6vw, 100px);
  font-weight: 800; line-height: 1.05; letter-spacing: -0.04em;
  margin-bottom: 24px;
}
.hero p {
  font-size: clamp(20px, 2vw, 26px);
  color: rgba(255,255,255,0.9); max-width: 800px; margin-bottom: 40px; line-height: 1.4;
}

/* Base Layouts */
section { padding: 160px 40px; }
.container { max-width: 1300px; margin: 0 auto; position: relative; }

.section-bg-gray { background-color: var(--bg-gray); border-radius: var(--border-radius-lg); margin: 20px; padding: 140px 40px;}
.section-bg-dark { background-color: var(--bg-dark); border-radius: var(--border-radius-lg); margin: 20px; padding: 140px 40px; color: #fff;}

.section-title {
  font-size: clamp(48px, 5vw, 72px);
  font-weight: 800; letter-spacing: -0.04em;
  margin-bottom: 32px; line-height: 1.05; text-align: center;
}
.section-subtitle {
  font-size: 24px; color: var(--text-secondary);
  max-width: 800px; margin: 0 auto 80px; line-height: 1.4; text-align: center;
}
.section-bg-dark .section-title { color: #fff; }
.section-bg-dark .section-subtitle { color: rgba(255,255,255,0.7); }

/* Grid Layouts - Meta Style Offset */
.feature-block {
  display: grid; grid-template-columns: 1.2fr 1fr; gap: 80px; align-items: center; margin-bottom: 120px;
}
.feature-block:nth-child(even) { grid-template-columns: 1fr 1.2fr; }
.feature-block:nth-child(even) .feature-text { order: 1; }
.feature-block:nth-child(even) .feature-media { order: 2; }

@media(max-width: 900px) {
  .feature-block, .feature-block:nth-child(even) { grid-template-columns: 1fr; gap: 40px; }
  .feature-block:nth-child(even) .feature-text { order: 2; }
  .feature-block:nth-child(even) .feature-media { order: 1; }
}

.feature-media {
  border-radius: var(--border-radius-lg); overflow: hidden;
  position: relative; aspect-ratio: 4/3;
  box-shadow: 0 32px 64px rgba(0,0,0,0.1);
}
.feature-media img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 1.2s cubic-bezier(0.16, 1, 0.3, 1);
}
.feature-media:hover img { transform: scale(1.05); }

.feature-text h2 { font-size: 56px; font-weight: 800; line-height: 1.05; letter-spacing: -0.03em; margin-bottom: 24px; }
.feature-text p { font-size: 20px; color: var(--text-secondary); margin-bottom: 24px; line-height: 1.5; }

/* Grid Cards */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }

.meta-card {
  background: #fff; padding: 48px; border-radius: var(--border-radius-md);
  box-shadow: 0 4px 20px rgba(0,0,0,0.03);
  transition: transform 0.4s ease, box-shadow 0.4s ease;
}
.meta-card:hover { transform: translateY(-8px); box-shadow: 0 20px 40px rgba(0,0,0,0.08); }
.section-bg-gray .meta-card { background: #fff; border: none; }
.meta-card h3 { font-size: 28px; font-weight: 700; margin-bottom: 16px; letter-spacing: -0.02em; }
.meta-card p { font-size: 18px; color: var(--text-secondary); line-height: 1.5; }
.card-icon-lg { font-size: 40px; margin-bottom: 32px; display: block; }

/* SHDH Massive Overlay block */
.massive-overlay {
  position: relative; border-radius: var(--border-radius-lg);
  overflow: hidden; min-height: 700px; display: flex; align-items: center; justify-content: center;
  box-shadow: 0 40px 80px rgba(0,0,0,0.15); margin: 80px 20px;
}
.img-zoom-scroll {
  position: absolute; top:0; left:0; width:100%; height:100%; object-fit: cover; z-index: 1;
}
.overlay-content {
  position: relative; z-index: 3;
  background: rgba(255,255,255,0.9);
  backdrop-filter: blur(30px);
  -webkit-backdrop-filter: blur(30px);
  padding: 80px; border-radius: var(--border-radius-md);
  max-width: 800px; text-align: center;
  margin: 40px;
}

/* Animations */
.fade-up {
  opacity: 0; transform: translateY(60px);
  transition: opacity 1s cubic-bezier(0.16, 1, 0.3, 1), transform 1s cubic-bezier(0.16, 1, 0.3, 1);
}
.fade-up.visible { opacity: 1; transform: translateY(0); }
.delay-100 { transition-delay: 0.1s; }
.delay-200 { transition-delay: 0.2s; }
.delay-300 { transition-delay: 0.3s; }

/* Team Layout Meta Style */
.team-wrap { display: flex; flex-direction: column; gap: 80px; margin-top: 80px; }
.team-row { display: grid; grid-template-columns: 350px 1fr; gap: 64px; align-items: center; }
.team-avatar-lg { width: 100%; aspect-ratio: 1; border-radius: var(--border-radius-md); object-fit: cover; box-shadow: 0 20px 40px rgba(0,0,0,0.1); }
.team-info h3 { font-size: 40px; font-weight: 800; margin-bottom: 8px; letter-spacing: -0.02em; }
.team-info .role { font-size: 20px; color: var(--primary); font-weight: 600; margin-bottom: 24px; text-transform: uppercase; letter-spacing: 1px;}
.team-info p { font-size: 22px; color: var(--text-secondary); line-height: 1.5; }

/* Parallax Classes (Fixed) */
.parallax-section {
  position: relative;
  background-attachment: fixed;
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}
.parallax-overlay {
  position: absolute; top:0; left:0; width:100%; height:100%; z-index: 1;
}
.parallax-section .container { position: relative; z-index: 2; }

/* Chim Lạc and Sun Animation Effect */
.sun-effect {
  position: absolute;
  top: 30%; left: 50%;
  transform: translate(-50%, -50%);
  width: 300px; height: 300px;
  background: radial-gradient(circle, rgba(255, 215, 0, 0.5) 0%, rgba(255, 140, 0, 0) 70%);
  border-radius: 50%;
  z-index: -1;
  pointer-events: none;
  animation: pulse-sun 4s infinite alternate;
}
@keyframes pulse-sun {
  0% { transform: translate(-50%, -50%) scale(1); opacity: 0.8; }
  100% { transform: translate(-50%, -50%) scale(1.2); opacity: 1; }
}
.global-chim-lac-flock {
  position: fixed; top: 0; left: 0; width: 100vw; height: 100vh;
  z-index: 9999; pointer-events: none; overflow: hidden;
}
.chim-lac-svg {
  position: absolute;
  fill: #eab308; opacity: 0.85; /* Gold color */
  filter: drop-shadow(0 0 12px rgba(234, 179, 8, 0.4));
  animation: fly-up linear infinite;
  transform-origin: center;
}
.chim-lac-svg:nth-child(1) { bottom: -20%; left: 10%; width: 120px; animation-duration: 25s; animation-delay: 0s; }
.chim-lac-svg:nth-child(2) { bottom: -20%; left: 40%; width: 90px; animation-duration: 35s; animation-delay: 5s; }
.chim-lac-svg:nth-child(3) { bottom: -20%; left: 70%; width: 150px; animation-duration: 30s; animation-delay: 12s; }
.chim-lac-svg:nth-child(4) { bottom: -20%; left: 25%; width: 100px; animation-duration: 28s; animation-delay: 20s; }
.chim-lac-svg:nth-child(5) { bottom: -20%; left: 85%; width: 130px; animation-duration: 40s; animation-delay: 8s; }

@keyframes fly-up {
  0% { transform: translateY(120vh) translateX(0) scale(1) rotate(-10deg); opacity: 0; }
  10% { opacity: 0.8; }
  90% { opacity: 0.8; }
  100% { transform: translateY(-30vh) translateX(30vw) scale(0.8) rotate(-20deg); opacity: 0; }
}

/* Form Area */
.form-container {
  max-width: 600px; margin: 0 auto;
  background: #fff; padding: 64px; border-radius: var(--border-radius-md);
  box-shadow: 0 32px 64px rgba(0,0,0,0.1);
}
.form-input {
  width: 100%; padding: 18px 24px; margin-bottom: 24px;
  background: var(--bg-gray); border: 2px solid transparent;
  border-radius: 16px; font-size: 18px; font-weight: 500; font-family: inherit;
  transition: border-color 0.3s;
}
.form-input:focus { outline: none; border-color: var(--primary); background: #fff; }

footer {
  padding: 100px 40px 60px; text-align: center;
  color: var(--text-secondary);
}

@media(max-width: 768px) {
  section { padding: 100px 20px; }
  .section-bg-gray, .section-bg-dark, .massive-overlay { margin: 0; border-radius: 0; }
  .hero { padding: 120px 20px 60px; }
  .team-row { grid-template-columns: 1fr; gap: 32px; }
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .overlay-content { padding: 40px 20px; }
}