:root {
  --primary: #3a78b7;
  --accent: #a6c9eb;
  --bg-light: #f4f8fd;
  --text: #243142;
  --white: #ffffff;
  --black: #000000;

  /* Theme specific */
  --bg: var(--bg-light);
  --text-color: var(--text);
  --card-bg: var(--white);
}

body.dark-mode {
  --bg: #1e1e1e;
  --text-color: #e0e0e0;
  --card-bg: #2c2c2c;
}
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      background-color: var(--bg);
      color: var(--text-color);
      font-family: 'Inter', sans-serif;
      line-height: 1.7;
      transition: background 0.4s ease, color 0.4s ease;
    }

    h1, h2, h3, h4 {
    font-family: 'Playfair Display', serif;
    font-weight: 600;
    line-height: 1.3;
    color: var(--primary);
    margin-bottom: 0.5em;
    }

    h1 {
    font-size: 3.2rem;
    }

    h2 {
    font-size: 2.2rem;
    }

    h3 {
    font-size: 1.5rem;
    }

    p {
    margin-bottom: 1.2em;
    max-width: 70ch;
    margin-left: auto;
    margin-right: auto;
    }

    .btn {
    font-family: 'Inter', sans-serif;
    font-weight: 500;
    letter-spacing: 0.4px;
    }
    /* Utility Classes */
    .text-center { text-align: center; }
    .text-left { text-align: left; }
    .text-right { text-align: right; }

    .mt-1 { margin-top: 1rem; }
    .mt-2 { margin-top: 2rem; }
    .mb-1 { margin-bottom: 1rem; }
    .mb-2 { margin-bottom: 2rem; }

    .p-1 { padding: 1rem; }
    .p-2 { padding: 2rem; }
    .py-2 { padding-top: 2rem; padding-bottom: 2rem; }
    .px-2 { padding-left: 2rem; padding-right: 2rem; }

    .flex-center {
      display: flex;
      justify-content: center;
      align-items: center;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border-radius: 50px;
      padding: 12px 28px;
      text-decoration: none;
      font-weight: bold;
      font-size: 1rem;
      display: inline-block;
      transition: background 0.3s ease;
      box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    }

    .btn-primary:hover {
      background: #2f6aa1;
    }

    .container {
      max-width: 960px;
      margin: auto;
      padding: 0 1rem;
    }
    nav {
      position: sticky;
      top: 0;
      width: 100%;
      background: var(--primary);
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
      display: flex;
      justify-content: center;
      gap: 30px;
      padding: 15px 0;
      z-index: 999;
    }

    nav a {
      color: white;
      text-decoration: none;
      font-weight: bold;
      letter-spacing: 0.5px;
      font-size: 1rem;
      transition: opacity 0.3s;
    }

    nav a:hover {
      opacity: 0.7;
    }

    header {
    height: 100vh;
    position: relative;
    background: url('./images/site_airial.jpg') center/cover no-repeat;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: white;
    overflow: hidden;
  }

  /* Semi-transparent overlay for readability */
  header::before {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(to bottom right, rgba(58, 120, 183, 0.55), rgba(58, 120, 183, 0.35));
    z-index: 1;
  }

    .hero-content {
      position: relative;
      z-index: 2;
      animation: fadeIn 1.2s ease-out;
    }
    .hero-content img {
      width: 80%;
      height: auto;
      background: rgba(0, 0, 0, 0.4);
      padding: 10px;
      border-radius: 10px;
      box-shadow: 0 4px 12px rgba(0,0,0,0.3);
    }
    .hero-content {
      text-align: center;
    }

    .hero-content img {
      display: block;
      margin: 0 auto 20px;
    }
    header h1 {
      font-family: 'Playfair Display', serif;
      font-size: 3.5rem;
      margin-bottom: 0.5rem;
      color: #fff;
      text-shadow: 0 2px 8px rgba(0,0,0,0.6);
    }

    header p {
      font-size: 1.2rem;
      margin-bottom: 1.5rem;
      color: #eee;
      text-shadow: 0 2px 8px rgba(0,0,0,0.6);
    }

    .btn {
    background: var(--primary);
    color: white;
    padding: 12px 28px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: bold;
    font-size: 1rem;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    transition: background 0.3s ease;
    }

    .btn:hover {
    background: #2f6aa1; /* Slightly darker blue */
    }


    section {
      padding: 100px 20px;
      max-width: 960px;
      margin: auto;
      text-align: center;
      background: var(--bg);
      transition: background 0.4s ease, color 0.4s ease;
    }

    section h2 {
      font-family: 'Playfair Display', serif;
      font-size: 2rem;
      margin-bottom: 15px;
      color: var(--primary);
      position: relative;
    }

    section h2::after {
      content: "";
      display: block;
      width: 60px;
      height: 3px;
      margin: 10px auto;
      background: var(--accent);
    }

    .icon-feature {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 40px;
      margin-top: 40px;
    }

    .icon-feature div {
      max-width: 250px;
      padding: 20px;
      background: white;
      border-radius: 15px;
      box-shadow: 0 4px 12px rgba(0,0,0,0.06);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
    }

    .icon-feature div:hover {
      transform: translateY(-6px);
      box-shadow: 0 8px 20px rgba(0,0,0,0.12);
    }

    .icon-feature i {
      font-size: 2.2rem;
      margin-bottom: 10px;
      color: var(--primary);
    }

    footer {
      background: var(--primary);
      color: white;
      text-align: center;
      padding: 40px 20px;
      font-size: 0.9rem;
    }

    @keyframes fadeIn {
      0% { opacity: 0; transform: translateY(30px); }
      100% { opacity: 1; transform: translateY(0); }
    }

    @media (max-width: 768px) {
      header h1 { font-size: 2.5rem; }
      .icon-feature { flex-direction: column; align-items: center; }
    }
    h2::after {
    content: "";
    display: block;
    width: 50px;
    height: 3px;
    background: var(--accent);
    margin: 12px auto 0;
    opacity: 0.7;
    }
    #backToTop {
      position: fixed;
      bottom: 30px;
      right: 30px;
      background: var(--primary);
      color: white;
      font-size: 1.2rem;
      padding: 10px 14px;
      border-radius: 50%;
      text-decoration: none;
      box-shadow: 0 4px 12px rgba(0,0,0,0.3);
      display: none;
      transition: opacity 0.3s ease, transform 0.3s ease;
      z-index: 1000;
    }

    #backToTop:hover {
      opacity: 0.85;
      transform: translateY(-2px);
    }
    .gallery {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
      gap: 20px;
      margin-top: 40px;
    }

    .gallery img {
      width: 100%;
      aspect-ratio: 4 / 3;
      object-fit: cover;
      border-radius: 10px;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      cursor: pointer;
    }

    .gallery img:hover {
      transform: scale(1.03);
      box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
    }
    .lightbox {
      display: none;
      position: fixed;
      z-index: 1001;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(0, 0, 0, 0.8);
      align-items: center;
      justify-content: center;
    }

    .lightbox-img {
      max-width: 90%;
      max-height: 80%;
      border-radius: 10px;
    }

    .lightbox .close {
      position: absolute;
      top: 30px;
      right: 40px;
      font-size: 2rem;
      color: white;
      cursor: pointer;
    }