/* Modern Bright Theme CSS - Phong cách hiện đại sáng sủa */

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

:root {
  /* Modern color palette - bright and contemporary */
  --primary: #3b82f6;
  --primary-50: #eff6ff;
  --primary-100: #dbeafe;
  --primary-500: #3b82f6;
  --primary-600: #2563eb;
  --primary-700: #1d4ed8;
  --primary-800: #1e40af;
  
  --secondary: #06b6d4;
  --secondary-50: #ecfeff;
  --secondary-100: #cffafe;
  --secondary-500: #06b6d4;
  --secondary-600: #0891b2;
  
  --accent: #f59e0b;
  --accent-50: #fffbeb;
  --accent-100: #fef3c7;
  --accent-500: #f59e0b;
  --accent-600: #d97706;
  
  --success: #10b981;
  --success-50: #ecfdf5;
  --success-500: #10b981;
  
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
  
  --white: #ffffff;
  --black: #000000;
  
  /* Modern spacing scale */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  
  /* Modern typography */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  --text-6xl: 3.75rem;
  
  /* Modern shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);
  
  /* Modern border radius */
  --radius-sm: 0.375rem;
  --radius: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-2xl: 2rem;
  --radius-full: 9999px;
  
  /* Modern transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Import modern font */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

html {
  font-size: 16px;
  line-height: 1.6;
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: linear-gradient(135deg, var(--gray-50) 0%, var(--white) 100%);
  color: var(--gray-900);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Utility Classes */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.font-light { font-weight: 300; }
.font-normal { font-weight: 400; }
.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold { font-weight: 700; }
.font-extrabold { font-weight: 800; }

.text-xs { font-size: var(--text-xs); }
.text-sm { font-size: var(--text-sm); }
.text-base { font-size: var(--text-base); }
.text-lg { font-size: var(--text-lg); }
.text-xl { font-size: var(--text-xl); }
.text-2xl { font-size: var(--text-2xl); }
.text-3xl { font-size: var(--text-3xl); }
.text-4xl { font-size: var(--text-4xl); }

.text-gray-500 { color: var(--gray-500); }
.text-gray-600 { color: var(--gray-600); }
.text-gray-700 { color: var(--gray-700); }

/* Modern Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--space-4);
  color: var(--gray-900);
  letter-spacing: -0.025em;
}

h1 {
  font-size: var(--text-5xl);
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary-600), var(--secondary-500));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

h2 {
  font-size: var(--text-4xl);
  font-weight: 700;
}

h3 {
  font-size: var(--text-3xl);
  font-weight: 600;
}

h4 {
  font-size: var(--text-2xl);
  font-weight: 600;
}

p {
  margin-bottom: var(--space-4);
  color: var(--gray-700);
  line-height: 1.7;
}

/* Links */
a {
  color: var(--primary-600);
  text-decoration: none;
  transition: all var(--transition-fast);
}

a:hover {
  color: var(--primary-700);
  text-decoration: underline;
}

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

/* Modern Header */
.topbar {
  background: linear-gradient(135deg, var(--primary-600), var(--primary-700));
  color: var(--white);
  padding: var(--space-3) 0;
  text-align: center;
  font-weight: 600;
  font-size: var(--text-sm);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  box-shadow: var(--shadow-sm);
}

.header-main {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--gray-200);
  padding: var(--space-6) 0;
  position: sticky;
  top: 0;
  z-index: 50;
  transition: all var(--transition);
}

.header-row {
  display: flex;
  align-items: center;
  gap: var(--space-8);
  flex-wrap: wrap;
}

.logo {
  flex-shrink: 0;
}

.logo img {
  height: 60px;
  transition: transform var(--transition);
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.1));
}

.logo:hover img {
  transform: scale(1.05);
}

/* Modern Search */
.search {
  flex: 1;
  max-width: 600px;
  position: relative;
}

.search input {
  width: 100%;
  padding: var(--space-4) var(--space-6);
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-full);
  background: var(--white);
  font-size: var(--text-base);
  outline: none;
  transition: all var(--transition);
  box-shadow: var(--shadow-sm);
}

.search input:focus {
  border-color: var(--primary-500);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
  transform: translateY(-1px);
}

.btn-search {
  position: absolute;
  right: var(--space-2);
  top: 50%;
  transform: translateY(-50%);
  background: var(--primary-500);
  color: var(--white);
  border: none;
  border-radius: var(--radius-full);
  padding: var(--space-3);
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition);
}

.btn-search:hover {
  background: var(--primary-600);
  transform: translateY(-50%) scale(1.05);
}

/* Social Links */
.socials {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.socials a {
  color: var(--gray-600);
  background: var(--white);
  padding: var(--space-3);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  transition: all var(--transition);
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
}

.socials a:hover {
  color: var(--primary-600);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

/* Flags */
.flags {
  display: flex;
  gap: var(--space-2);
  margin-left: var(--space-4);
}

.flag {
  background: none;
  border: none;
  padding: var(--space-2);
  cursor: pointer;
  transition: transform var(--transition);
  border-radius: var(--radius);
}

.flag:hover {
  transform: scale(1.1);
}

/* Modern Navigation */
.main-menu {
  background: linear-gradient(135deg, var(--primary-600), var(--primary-700));
  box-shadow: var(--shadow-lg);
}

.main-menu ul {
  display: flex;
  gap: var(--space-2);
  list-style: none;
  /* padding: var(--space-4) var(--space-6); */
  align-items: center;
  flex-wrap: wrap;
  justify-content: center;
}

.main-menu a {
  color: var(--white);
  text-decoration: none;
  font-weight: 600;
  font-size: var(--text-sm);
  padding: var(--space-3) var(--space-5);
  border-radius: var(--radius-lg);
  display: inline-block;
  transition: all var(--transition);
  text-transform: uppercase;
  letter-spacing: 0.025em;
  position: relative;
  overflow: hidden;
}

.main-menu a::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.5s;
}

.main-menu a:hover::before {
  left: 100%;
}

.main-menu a:hover {
  background: rgba(255, 255, 255, 0.15);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

/* Modern Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-4) var(--space-6);
  border: none;
  border-radius: var(--radius-lg);
  font-weight: 600;
  font-size: var(--text-base);
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--primary-500), var(--primary-600));
  color: var(--white);
  box-shadow: var(--shadow-md);
  text-transform: uppercase;
  letter-spacing: 0.025em;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s;
}

.btn:hover::before {
  left: 100%;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
}

.btn.secondary {
  background: linear-gradient(135deg, var(--accent-500), var(--accent-600));
  color: var(--white);
}

.btn.outline {
  background: transparent;
  color: var(--primary-600);
  border: 2px solid var(--primary-500);
}

.btn.outline:hover {
  background: var(--primary-500);
  color: var(--white);
}

/* Modern Banner */
.banner {
  position: relative;
  margin: var(--space-8) 0;
  border-radius: var(--radius-2xl);
  overflow: hidden;
  box-shadow: var(--shadow-2xl);
}

.banner .slides {
  position: relative;
  height: 500px;
}

.banner .slide {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background-size: cover;
  background-position: center;
  transition: all 1s cubic-bezier(0.4, 0, 0.2, 1);
  opacity: 0;
  transform: scale(1.1);
}

.banner .slide.active {
  opacity: 1;
  transform: scale(1);
}

.banner .slide .overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(30, 41, 59, 0.7), rgba(59, 130, 246, 0.3));
}

.banner .slide .content {
  position: relative;
  z-index: 2;
  max-width: 800px;
  color: var(--white);
  text-align: center;
  padding: var(--space-8);
}

.banner h1 {
  font-size: var(--text-5xl);
  font-weight: 800;
  margin-bottom: var(--space-6);
  text-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
  background: linear-gradient(135deg, var(--white), var(--gray-200));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.banner p {
  font-size: var(--text-xl);
  margin-bottom: var(--space-8);
  color: var(--gray-100);
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

/* Modern Banner CTAs */
.banner-ctas {
  text-align: center;
  margin: var(--space-10) 0;
}

.banner-ctas .btn {
  margin: 0 var(--space-3);
  padding: var(--space-5) var(--space-8);
  font-size: var(--text-lg);
}

/* Modern Sections */
.section {
  padding: var(--space-16) 0;
}

.section:nth-child(even) {
  background: linear-gradient(135deg, var(--gray-50), rgba(255, 255, 255, 0.8));
}

/* Modern Grid */
.grid {
  display: grid;
  grid-template-columns: 1fr 400px;
  gap: var(--space-12);
  align-items: start;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-8);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-8);
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-6);
}

/* Modern Cards */
.card {
  background: var(--white);
  padding: var(--space-8);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  transition: all var(--transition);
  border: 1px solid var(--gray-100);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(135deg, var(--primary-500), var(--secondary-500));
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2xl);
  border-color: var(--primary-200);
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-8);
}

.card .title {
  font-weight: 700;
  font-size: var(--text-xl);
  margin-bottom: var(--space-4);
  color: var(--gray-900);
}

.card .meta {
  color: var(--gray-500);
  font-size: var(--text-sm);
  font-weight: 500;
}

/* Modern Counter/Stats */
.achievements-banner {
  background: linear-gradient(135deg, var(--primary-50), var(--secondary-50));
  padding: var(--space-12);
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-xl);
  margin: var(--space-12) 0;
  border: 1px solid var(--gray-200);
}

.achievements-banner h3 {
  color: var(--gray-900);
  text-align: center;
  margin-bottom: var(--space-8);
  font-size: var(--text-3xl);
}

.counter {
  display: flex;
  gap: var(--space-6);
  align-items: stretch;
}

.counter .item {
  flex: 1;
  background: linear-gradient(135deg, var(--primary-500), var(--primary-600));
  padding: var(--space-8);
  border-radius: var(--radius-xl);
  text-align: center;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  transition: all var(--transition);
}

.counter .item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2xl);
}

.counter .item::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(45deg, transparent, rgba(255, 255, 255, 0.1), transparent);
  transform: rotate(45deg);
  transition: all var(--transition-slow);
}

.counter .item:hover::before {
  animation: shimmer 1.5s ease-in-out;
}

@keyframes shimmer {
  0% { transform: translateX(-100%) translateY(-100%) rotate(45deg); }
  100% { transform: translateX(100%) translateY(100%) rotate(45deg); }
}

.counter .num {
  font-size: var(--text-5xl);
  font-weight: 800;
  color: var(--white);
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  display: block;
  margin-bottom: var(--space-2);
}

.counter .small {
  color: var(--gray-100);
  font-weight: 600;
  font-size: var(--text-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Media Aspect Ratio */
.media-16by9 {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  transition: all var(--transition);
}

.media-16by9:hover {
  transform: scale(1.02);
  box-shadow: var(--shadow-xl);
}

.media-16by9 img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: all var(--transition);
}

.media-16by9:hover img {
  transform: scale(1.05);
}

/* Modern Footer */
footer {
  background: linear-gradient(135deg, var(--gray-900), var(--gray-800));
  color: var(--gray-100);
  padding: var(--space-20) 0;
  margin-top: var(--space-16);
  position: relative;
  overflow: hidden;
}

footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(135deg, var(--primary-500), var(--secondary-500));
}

footer::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100" fill="none"><defs><pattern id="footergrid" width="20" height="20" patternUnits="userSpaceOnUse"><path d="M 20 0 L 0 0 0 20" fill="none" stroke="rgba(255,255,255,0.02)" stroke-width="1"/></pattern></defs><rect width="100" height="100" fill="url(%23footergrid)"/></svg>');
  pointer-events: none;
}

.footer-container {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: var(--space-12);
  position: relative;
  z-index: 2;
}

/* Footer Brand */
.footer-brand h3 {
  color: var(--white);
  font-size: var(--text-2xl);
  margin-bottom: var(--space-4);
  background: linear-gradient(135deg, var(--primary-400), var(--secondary-400));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer-logo {
  width: 120px;
  height: auto;
  margin-bottom: var(--space-4);
  filter: brightness(1.2);
}

.footer-brand p {
  color: var(--gray-300);
  line-height: 1.7;
  margin-bottom: var(--space-8);
}

/* Footer Highlights */
.footer-highlights {
  display: flex;
  gap: var(--space-6);
  margin: var(--space-8) 0;
  flex-wrap: wrap;
}

.highlight-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  background: rgba(255, 255, 255, 0.05);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-full);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.highlight-item i {
  color: var(--primary-400);
  font-size: var(--text-sm);
}

.highlight-item span {
  color: var(--gray-200);
  font-size: var(--text-sm);
  font-weight: 500;
}

/* Footer Social Links */
.footer-socials {
  display: flex;
  gap: var(--space-4);
  margin-top: var(--space-6);
}

.social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.1);
  color: var(--white);
  text-decoration: none;
  transition: all var(--transition);
  border: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
}

.social-link:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
}

.social-link.facebook:hover {
  background: #1877F2;
  border-color: #1877F2;
}

.social-link.youtube:hover {
  background: #FF0000;
  border-color: #FF0000;
}

.social-link.tiktok:hover {
  background: linear-gradient(135deg, #25F4EE, #FF2C55);
  border-color: transparent;
}

.social-link.email:hover {
  background: var(--primary-500);
  border-color: var(--primary-500);
}

/* Footer Links */
.footer-links h4 {
  color: var(--white);
  font-size: var(--text-lg);
  margin-bottom: var(--space-6);
}

.footer-nav {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer-nav a {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  color: var(--gray-300);
  text-decoration: none;
  padding: var(--space-2) 0;
  transition: all var(--transition);
  border-radius: var(--radius);
}

.footer-nav a:hover {
  color: var(--primary-400);
  transform: translateX(4px);
}

.footer-nav a i {
  width: 16px;
  color: var(--primary-400);
  font-size: var(--text-sm);
}

/* Footer Contact */
.footer-contact h4 {
  color: var(--white);
  font-size: var(--text-lg);
  margin-bottom: var(--space-6);
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-3);
  background: rgba(255, 255, 255, 0.03);
  border-radius: var(--radius);
  border: 1px solid rgba(255, 255, 255, 0.05);
}

.contact-item i {
  color: var(--primary-400);
  font-size: var(--text-base);
  margin-top: 2px;
  flex-shrink: 0;
}

.contact-item div {
  flex: 1;
}

.contact-item strong {
  color: var(--white);
  font-size: var(--text-sm);
  display: block;
  margin-bottom: var(--space-1);
}

.contact-item span,
.contact-item a {
  color: var(--gray-300);
  font-size: var(--text-sm);
  text-decoration: none;
}

.contact-item a:hover {
  color: var(--primary-400);
}

/* Footer Bottom */
.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: var(--space-12);
  padding-top: var(--space-8);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.copyright {
  flex: 1;
}

.copyright p {
  margin: 0 0 var(--space-1);
  color: var(--gray-400);
  font-size: var(--text-sm);
}

.powered-by {
  font-size: var(--text-xs) !important;
}

.powered-by a {
  color: var(--primary-400);
  text-decoration: none;
}

.powered-by a:hover {
  color: var(--primary-300);
}

/* Footer Badges */
.footer-badges {
  display: flex;
  gap: var(--space-4);
}

.badge {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  background: rgba(255, 255, 255, 0.05);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-full);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.badge i {
  color: var(--accent-400);
  font-size: var(--text-xs);
}

.badge span {
  color: var(--gray-300);
  font-size: var(--text-xs);
  font-weight: 500;
}

/* Hamburger Menu */
.hamburger {
  display: none;
  background: var(--white);
  border: 2px solid var(--gray-200);
  padding: var(--space-3);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  cursor: pointer;
  transition: all var(--transition);
}

.hamburger:hover {
  background: var(--gray-50);
  transform: scale(1.05);
}

.hamburger.open {
  background: var(--primary-500);
  color: var(--white);
  border-color: var(--primary-500);
}

/* Mobile Navigation */
#main-nav.open {
  display: block;
  background: var(--primary-600);
  padding: var(--space-6);
  border-radius: var(--radius-lg);
  margin-top: var(--space-4);
  box-shadow: var(--shadow-xl);
}

#main-nav.open li {
  display: block;
  margin: var(--space-3) 0;
}

/* Animations */
.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.animate-on-scroll.in-view {
  opacity: 1;
  transform: translateY(0);
}

/* Floating Elements */
.floating-support {
  position: fixed;
  right: var(--space-6);
  bottom: 120px;
  z-index: 1050;
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  align-items: flex-end;
}

.floating-support .floating-btn {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  color: var(--white);
  box-shadow: var(--shadow-xl);
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  font-size: var(--text-lg);
}

.floating-support .floating-btn:hover {
  transform: translateY(-4px) scale(1.05);
  box-shadow: var(--shadow-2xl);
}

.call-btn {
  background: linear-gradient(135deg, var(--success-500), #16a34a);
}

.zalo-btn {
  background: linear-gradient(135deg, #0068FF, #0052CC);
}

.messenger-btn {
  background: linear-gradient(135deg, #0084FF, #0068D4);
}

/* Pulse Animation */
@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

.floating-support .floating-btn {
  animation: pulse 3s ease-in-out infinite;
}

/* Modern Responsive Design */
@media (max-width: 1024px) {
  .container {
    padding: 0 var(--space-4);
  }
  
  .grid {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }
  
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .header-row {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-4);
  }
  
  .search {
    order: 3;
    max-width: 100%;
  }
  
  .logo {
    order: 1;
    text-align: center;
  }
  
  .socials {
    order: 2;
    justify-content: center;
  }
  
  .banner .slide {
    height: 400px;
  }
  
  .banner h1 {
    font-size: var(--text-4xl);
  }
  
  .banner p {
    font-size: var(--text-lg);
  }
  
  .counter {
    flex-direction: column;
  }
  
  .footer-container {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-8);
  }
  
  .footer-brand {
    grid-column: 1 / -1;
  }
  
  .footer-highlights {
    justify-content: center;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: var(--space-6);
    text-align: center;
  }
}

@media (max-width: 768px) {
  :root {
    --space-16: 3rem;
    --space-20: 4rem;
  }
  
  .hamburger {
    display: block;
  }
  
  #main-nav {
    display: none;
  }
  
  .main-menu ul {
    justify-content: center;
    flex-wrap: wrap;
  }
  
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
  
  .cards {
    grid-template-columns: 1fr;
  }
  
  .footer-container {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }
  
  .footer-highlights {
    flex-direction: column;
    align-items: center;
    gap: var(--space-3);
  }
  
  .footer-socials {
    justify-content: center;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: var(--space-4);
    text-align: center;
  }
  
  .footer-badges {
    justify-content: center;
    flex-wrap: wrap;
  }
  
  .floating-support {
    right: var(--space-4);
    bottom: 100px;
  }
  
  .floating-support .floating-btn {
    width: 48px;
    height: 48px;
    font-size: var(--text-base);
  }
  
  h1 { font-size: var(--text-3xl); }
  h2 { font-size: var(--text-2xl); }
  h3 { font-size: var(--text-xl); }
  
  .banner h1 { font-size: var(--text-3xl); }
  .banner p { font-size: var(--text-base); }
  
  .counter .num { font-size: var(--text-4xl); }
}

@media (max-width: 480px) {
  .container {
    padding: 0 var(--space-3);
  }
  
  .card {
    padding: var(--space-6);
  }
  
  .btn {
    padding: var(--space-3) var(--space-5);
    font-size: var(--text-sm);
  }
  
  .banner .slide {
    height: 300px;
  }
  
  .banner h1 {
    font-size: var(--text-2xl);
  }
  
  .banner p {
    font-size: var(--text-sm);
  }
  
  .achievements-banner {
    padding: var(--space-8);
  }
  
  .counter .item {
    padding: var(--space-6);
  }
  
  .counter .num {
    font-size: var(--text-3xl);
  }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  
  .animate-on-scroll {
    opacity: 1;
    transform: none;
  }
}

/* Focus Styles */
*:focus {
  outline: 2px solid var(--primary-500);
  outline-offset: 2px;
}

/* Selection Styles */
::selection {
  background: var(--primary-500);
  color: var(--white);
}

/* Scrollbar Styles */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--gray-100);
}

::-webkit-scrollbar-thumb {
  background: var(--gray-400);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--gray-500);
}