:root {
  --primary-color: #FFC700;
  --bg-color: #121212;
  --card-bg: rgba(255, 255, 255, 0.05);
  --text-main: #f0f0f0;
  --text-muted: #a0a0a0;
  --border-color: rgba(255, 255, 255, 0.1);
  --font-family: 'Inter', system-ui, -apple-system, sans-serif;
  --accent-color: #D4A500;
}

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

body {
  background-color: var(--bg-color);
  color: var(--text-main);
  font-family: var(--font-family);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Header */
.site-header {
  padding: 1.5rem 5%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border-color);
  background: rgba(18, 18, 18, 0.8);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo a {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
  letter-spacing: 1px;
}

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

.nav-links a {
  color: var(--text-main);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary-color);
}

/* Hamburger Button */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  z-index: 200;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-main);
  border-radius: 2px;
  transition: all 0.3s ease;
}

.hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.hamburger.open span:nth-child(2) {
  opacity: 0;
}
.hamburger.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Hero Section */
.hero {
  padding: 5rem 5%;
  text-align: center;
  background: radial-gradient(circle at center, rgba(255, 199, 0, 0.1) 0%, transparent 70%);
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  background: linear-gradient(135deg, #FFC700, #f0f0f0);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero p {
  font-size: 1.2rem;
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto;
}

/* Main Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 5%;
}

/* Card Grid */
.grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
  margin-top: 2rem;
}

@media (max-width: 768px) {
  .grid {
    grid-template-columns: 1fr;
  }
}

/* Glassmorphism Cards */
.card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 2rem;
  backdrop-filter: blur(5px);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
  display: flex;
  flex-direction: column;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  border-color: var(--primary-color);
}

.card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
}

.card p {
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.card-action {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  background: rgba(255, 199, 0, 0.1);
  color: var(--primary-color);
  text-decoration: none;
  border-radius: 8px;
  font-weight: 600;
  text-align: center;
  transition: all 0.3s ease;
  border: 1px solid rgba(255, 199, 0, 0.3);
}

.card-action:hover {
  background: var(--primary-color);
  color: var(--bg-color);
}

/* =============================================
   LIGHTBOX — Click-to-expand images
   ============================================= */
.img-thumb {
  width: 100%;
  height: 180px;
  object-fit: cover;
  border-radius: 8px;
  margin-bottom: 1.25rem;
  border: 1px solid var(--border-color);
  cursor: zoom-in;
  transition: opacity 0.2s ease, transform 0.2s ease;
  display: block;
}

.img-thumb:hover {
  opacity: 0.88;
  transform: scale(1.01);
}

/* Lightbox overlay */
.lightbox-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.92);
  z-index: 9999;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  cursor: zoom-out;
  backdrop-filter: blur(6px);
}

.lightbox-overlay.active {
  display: flex;
}

.lightbox-overlay img {
  max-width: 95vw;
  max-height: 92vh;
  object-fit: contain;
  border-radius: 12px;
  box-shadow: 0 30px 80px rgba(0,0,0,0.8);
  cursor: default;
  animation: lb-in 0.22s ease;
}

@keyframes lb-in {
  from { opacity: 0; transform: scale(0.93); }
  to   { opacity: 1; transform: scale(1); }
}

.lightbox-close {
  position: fixed;
  top: 1.25rem;
  right: 1.5rem;
  background: rgba(255,255,255,0.12);
  border: none;
  color: #fff;
  font-size: 1.8rem;
  line-height: 1;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s;
  z-index: 10000;
}

.lightbox-close:hover {
  background: rgba(255,255,255,0.25);
}

/* Wide banner variant (business-models) */
.img-banner {
  width: 100%;
  max-height: 400px;
  object-fit: cover;
  border-radius: 16px;
  margin-bottom: 2rem;
  border: 1px solid var(--border-color);
  cursor: zoom-in;
  transition: opacity 0.2s ease;
  display: block;
}

.img-banner:hover {
  opacity: 0.88;
}


.input-group {
  margin-bottom: 1.5rem;
}

.input-group label {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--text-muted);
}

.input-group input,
.input-group textarea,
.input-group select {
  width: 100%;
  padding: 0.75rem 1rem;
  background: rgba(0,0,0,0.2);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  color: var(--text-main);
  font-family: var(--font-family);
  transition: border-color 0.3s ease;
}

.input-group input:focus,
.input-group textarea:focus,
.input-group select:focus {
  outline: none;
  border-color: var(--primary-color);
}

/* Simple Footer */
.site-footer {
  text-align: center;
  padding: 3rem 5%;
  border-top: 1px solid var(--border-color);
  margin-top: 4rem;
  color: var(--text-muted);
}

/* =============================================
   RESPONSIVE DESIGN — MOBILE & TABLET
   ============================================= */

/* --- Tablet (≤ 1024px) --- */
@media (max-width: 1024px) {
  .grid {
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
  }

  .hero {
    padding: 4rem 5%;
  }

  .hero h1 {
    font-size: 2.5rem;
  }

  .article-content {
    padding: 2rem;
  }
}

/* --- Mobile (≤ 768px) --- */
@media (max-width: 768px) {
  /* Header: row with logo + hamburger */
  .site-header {
    flex-direction: row;
    justify-content: space-between;
    gap: 0;
    padding: 1rem 5%;
    flex-wrap: wrap;
  }

  /* Show hamburger */
  .hamburger {
    display: flex;
  }

  /* Nav slides in from top when open */
  .nav-links {
    display: none;
    flex-direction: column;
    width: 100%;
    gap: 0;
    background: rgba(18, 18, 18, 0.98);
    border-top: 1px solid var(--border-color);
    padding: 0.5rem 0;
    margin-top: 0.5rem;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links li {
    width: 100%;
  }

  .nav-links a {
    display: block;
    padding: 0.85rem 1.5rem;
    font-size: 1rem;
    border-bottom: 1px solid var(--border-color);
  }

  .nav-links a:last-child {
    border-bottom: none;
  }

  /* Hero section */
  .hero {
    padding: 3rem 5%;
  }

  .hero h1 {
    font-size: 1.8rem;
    line-height: 1.3;
  }

  .hero p {
    font-size: 1rem;
  }

  /* Grid: single column */
  .grid {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }

  /* Cards */
  .card {
    padding: 1.5rem;
  }

  .card h3 {
    font-size: 1.2rem;
  }

  /* Container */
  .container {
    padding: 1.5rem 5%;
  }

  /* Article content */
  .article-content {
    padding: 1.25rem;
    font-size: 1rem;
  }

  .article-content h1 {
    font-size: 1.8rem !important;
  }

  .article-content h2 {
    font-size: 1.3rem !important;
  }

  .article-content table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  /* Inputs: prevent iOS auto-zoom */
  input, select, textarea {
    font-size: 16px !important;
  }

  /* Footer */
  .site-footer {
    padding: 2rem 5%;
    font-size: 0.9rem;
  }
}

/* --- Small Mobile (≤ 480px) --- */
@media (max-width: 480px) {
  .logo a {
    font-size: 1.2rem;
  }

  .hero h1 {
    font-size: 1.5rem;
  }

  .card-action {
    display: block;
    text-align: center;
  }
}