/* ========================================
   PREMIUM VILLA DESIGN SYSTEM
   ======================================== */

/* CSS Variables */
:root {
  /* Colors */
  --primary: #0ea5e9;
  --primary-dark: #0284c7;
  --secondary: #f59e0b;
  --secondary-dark: #d97706;
  --accent: #8b5cf6;
  --dark: #0f172a;
  --dark-light: #1e293b;
  --light: #f8fafc;
  --gray: #64748b;
  --gray-light: #e2e8f0;
  
  /* Glass Effect */
  --glass-bg: rgba(255, 255, 255, 0.1);
  --glass-border: rgba(255, 255, 255, 0.2);
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;
  
  /* Typography */
  --font-body: 'Inter', sans-serif;
  --font-heading: 'Inter', sans-serif;
  
  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.2);
  
  /* Transitions */
  --transition: 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  color: var(--dark);
  line-height: 1.7;
  overflow-x: hidden;
}

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

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  line-height: 1.2;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.75rem); }

p {
  margin-bottom: var(--spacing-sm);
  color: var(--gray);
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

/* Section Spacing */
section {
  padding: var(--spacing-xl) 0;
}

/* Navigation */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(15, 23, 42, 0.95);
  backdrop-filter: blur(10px);
  padding: 1rem 0;
  box-shadow: var(--shadow-sm);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-link {
  color: #fff;
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: 8px;
  transition: var(--transition);
}

.nav-link:hover {
  background: var(--glass-bg);
  transform: translateY(-2px);
}

/* Mobile Menu Toggle */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 0.5rem;
}

.menu-toggle span {
  width: 25px;
  height: 3px;
  background: #fff;
  border-radius: 3px;
  transition: var(--transition);
}

/* Hero Section */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: #fff;
  overflow: hidden;
  padding-top: 80px;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(14, 165, 233, 0.8), rgba(245, 158, 11, 0.6));
  z-index: 1;
}

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

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 900px;
  padding: var(--spacing-md);
}

.hero h1 {
  margin-bottom: var(--spacing-md);
  text-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
}

.hero p {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-md);
  color: rgba(255, 255, 255, 0.95);
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 1rem 2.5rem;
  border-radius: 50px;
  font-weight: 700;
  transition: var(--transition);
  cursor: pointer;
  border: none;
  font-size: 1rem;
}

.btn-primary {
  background: linear-gradient(135deg, var(--secondary), var(--secondary-dark));
  color: var(--dark);
  box-shadow: 0 4px 16px rgba(245, 158, 11, 0.4);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 24px rgba(245, 158, 11, 0.5);
}

.btn-secondary {
  background: transparent;
  color: #fff;
  border: 2px solid #fff;
}

.btn-secondary:hover {
  background: #fff;
  color: var(--dark);
}

/* Grid System */
.grid {
  display: grid;
  gap: var(--spacing-md);
}

.grid-2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid-4 { grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); }

/* Cards */
.card {
  background: #fff;
  border-radius: 20px;
  padding: var(--spacing-md);
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  height: 100%;
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.card-icon {
  font-size: 3rem;
  margin-bottom: var(--spacing-sm);
}

.card h3 {
  color: var(--dark);
  margin-bottom: var(--spacing-sm);
}

.card p {
  color: var(--gray);
}

/* Glass Card */
.glass-card {
  background: var(--glass-bg);
  backdrop-filter: blur(10px);
  border: 1px solid var(--glass-border);
  border-radius: 20px;
  padding: var(--spacing-md);
  color: #fff;
}

/* Image Gallery */
.gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}

.gallery-item {
  position: relative;
  overflow: hidden;
  border-radius: 16px;
  cursor: pointer;
  aspect-ratio: 4/3;
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition);
}

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

.gallery-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(to top, rgba(0,0,0,0.7), transparent);
  opacity: 0;
  transition: var(--transition);
  display: flex;
  align-items: flex-end;
  padding: var(--spacing-md);
  color: #fff;
}

.gallery-item:hover .gallery-overlay {
  opacity: 1;
}

/* Pricing Cards */
.pricing-card {
  background: #fff;
  border-radius: 24px;
  padding: var(--spacing-md);
  text-align: center;
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  border: 3px solid transparent;
}

.pricing-card.featured {
  border-color: var(--primary);
  transform: scale(1.05);
}

.pricing-card:hover {
  transform: translateY(-10px) scale(1.02);
  box-shadow: var(--shadow-lg);
}

.price {
  font-size: 3rem;
  font-weight: 700;
  color: var(--primary);
  margin: var(--spacing-sm) 0;
}

.price-unit {
  font-size: 1rem;
  color: var(--gray);
}

/* Testimonials */
.testimonial {
  background: var(--light);
  border-radius: 20px;
  padding: var(--spacing-md);
  position: relative;
}

.testimonial-stars {
  color: var(--secondary);
  font-size: 1.5rem;
  margin-bottom: var(--spacing-sm);
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-top: var(--spacing-md);
}

.testimonial-avatar {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  object-fit: cover;
}

/* FAQ */
.faq-item {
  background: #fff;
  border-radius: 12px;
  margin-bottom: 1rem;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.faq-question {
  padding: 1.5rem;
  cursor: pointer;
  font-weight: 600;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition);
}

.faq-question:hover {
  background: var(--light);
}

.faq-answer {
  padding: 0 1.5rem 1.5rem;
  color: var(--gray);
  display: none;
}

.faq-item.active .faq-answer {
  display: block;
}

/* Footer */
footer {
  background: var(--dark);
  color: #fff;
  padding: var(--spacing-lg) 0 var(--spacing-md);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
}

.footer-section h3 {
  color: #fff;
  margin-bottom: var(--spacing-sm);
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 0.5rem;
}

.footer-links a {
  color: var(--gray-light);
}

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

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--dark-light);
  color: var(--gray);
}

/* Floating CTA */
.float-cta {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.float-btn {
  padding: 1rem 1.5rem;
  border-radius: 50px;
  color: #fff;
  font-weight: 700;
  box-shadow: var(--shadow-lg);
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.float-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.btn-call { background: linear-gradient(135deg, #2563eb, #1d4ed8); }
.btn-zalo { background: linear-gradient(135deg, #0ea5e9, #0284c7); }

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

.fade-in-up {
  animation: fadeInUp 0.6s ease-out;
}

/* Responsive */
@media (max-width: 768px) {
  .nav-menu {
    position: fixed;
    top: 70px;
    left: -100%;
    flex-direction: column;
    background: var(--dark);
    width: 100%;
    padding: 2rem;
    transition: var(--transition);
  }
  
  .nav-menu.active {
    left: 0;
  }
  
  .menu-toggle {
    display: flex;
  }
  
  .hero {
    min-height: 80vh;
  }
  
  section {
    padding: var(--spacing-lg) 0;
  }
  
  .float-cta {
    bottom: 1rem;
    right: 1rem;
  }
  
  .float-btn {
    padding: 0.75rem 1.25rem;
    font-size: 0.9rem;
  }
}

/* Utility Classes */
.text-center { text-align: center; }
.text-primary { color: var(--primary); }
.text-secondary { color: var(--secondary); }
.bg-light { background: var(--light); }
.bg-dark { background: var(--dark); color: #fff; }
.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }