* {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
      font-family: 'Inter', sans-serif;
    }

    :root {
      --primary: #6366f1;
      --primary-dark: #4f46e5;
      --primary-light: #818cf8;
      --accent: #f43f5e;
      --accent-dark: #e11d48;
      --neutral-100: #0f172a;
      --neutral-200: #1e293b;
      --neutral-300: #334155;
      --neutral-700: #cbd5e1;
      --neutral-900: #f1f5f9;
      --success: #10b981;
      --card-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
      --transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
      --border-radius: 20px;
    }

    body {
      background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
      color: var(--neutral-900);
      min-height: 100vh;
      overflow-x: hidden;
      padding-top: 50px;
    }

    /* Cyberpunk grid background */
    .cyber-grid {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      z-index: -2;
      opacity: 0.15;
      background-image: 
        linear-gradient(rgba(99, 102, 241, 0.2) 1px, transparent 1px),
        linear-gradient(90deg, rgba(99, 102, 241, 0.2) 1px, transparent 1px);
      background-size: 50px 50px;
      transform: perspective(500px) rotateX(60deg);
    }

    /* Floating elements */
    .floating-elements {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      z-index: -1;
      pointer-events: none;
    }

    .floating-element {
      position: absolute;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      opacity: 0.15;
      animation: float 20s infinite ease-in-out;
      filter: blur(25px);
    }

    .floating-element:nth-child(1) {
      width: 300px;
      height: 300px;
      top: 10%;
      left: 5%;
      animation-delay: 0s;
    }

    .floating-element:nth-child(2) {
      width: 200px;
      height: 200px;
      top: 65%;
      right: 8%;
      animation-delay: 5s;
    }

    .floating-element:nth-child(3) {
      width: 250px;
      height: 250px;
      bottom: 15%;
      left: 15%;
      animation-delay: 10s;
    }

    /* Marquee Banner */
    .marquee-container {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: linear-gradient(90deg, var(--primary-dark) 0%, var(--accent) 100%);
      color: white;
      padding: 0.8rem;
      font-size: 0.9rem;
      z-index: 1000;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
    }

    .marquee-container i {
      margin-right: 10px;
    }

    /* Navigation Bar */
    nav {
      background: rgba(30, 41, 59, 0.8);
      backdrop-filter: blur(15px);
      border: 1px solid rgba(99, 102, 241, 0.2);
      padding: 15px 5%;
      position: sticky;
      top: 40px;
      z-index: 1001;
      display: flex;
      align-items: center;
      justify-content: space-between;
      box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
      border-radius: var(--border-radius);
      margin: 0 20px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 12px;
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--neutral-900);
    }

    .logo i {
      font-size: 2.2rem;
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .nav-links {
      display: flex;
      gap: 25px;
    }

    .nav-links a {
      color: var(--neutral-700);
      text-decoration: none;
      font-weight: 500;
      padding: 10px 18px;
      border-radius: 12px;
      transition: var(--transition);
      position: relative;
    }

    .nav-links a:hover, .nav-links a.active {
      background: rgba(99, 102, 241, 0.1);
      color: var(--primary-light);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      width: 0;
      height: 3px;
      background: var(--accent);
      transition: var(--transition);
      transform: translateX(-50%);
      border-radius: 3px;
    }

    .nav-links a:hover::after, .nav-links a.active::after {
      width: 70%;
    }

    .search-container {
      position: relative;
    }

    .search-icon {
      position: absolute;
      left: 15px;
      top: 50%;
      transform: translateY(-50%);
      color: var(--neutral-700);
      z-index: 2;
    }

    #search-bar {
      padding: 12px 15px 12px 45px;
      border-radius: 50px;
      border: 1px solid var(--neutral-300);
      outline: none;
      background: rgba(30, 41, 59, 0.7);
      transition: var(--transition);
      width: 280px;
      font-size: 1rem;
      box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
      color: var(--neutral-900);
    }

    #search-bar:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1);
      width: 320px;
    }

    .menu-toggle {
      display: none;
      font-size: 1.6rem;
      background: none;
      border: none;
      color: var(--neutral-900);
      cursor: pointer;
    }

    /* Hero Section */
    .hero {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1400px;
      margin: 100px auto;
      padding: 0 40px;
      gap: 60px;
    }

    .hero-content {
      flex: 1;
    }

    .hero-content h1 {
      font-size: 3.5rem;
      margin-bottom: 20px;
      line-height: 1.2;
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-content p {
      font-size: 1.3rem;
      color: var(--neutral-700);
      margin-bottom: 40px;
      max-width: 600px;
      line-height: 1.6;
    }

    .hero-stats {
      display: flex;
      gap: 40px;
    }

    .stat {
      text-align: center;
      position: relative;
    }

    .stat-number {
      display: block;
      font-size: 2.8rem;
      font-weight: 800;
      color: var(--primary-light);
      margin-bottom: 5px;
      text-shadow: 0 0 20px rgba(99, 102, 241, 0.5);
    }

    .stat-label {
      font-size: 1rem;
      color: var(--neutral-700);
      font-weight: 500;
    }

    .daily-counter {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      margin-top: 8px;
      font-size: 0.9rem;
      color: var(--accent);
    }

    .calendar-icon {
      font-size: 1rem;
    }

    .hero-visual {
      flex: 1;
      position: relative;
      height: 400px;
    }

    .visual-container {
      position: relative;
      width: 100%;
      height: 100%;
    }

    .main-visual {
      width: 100%;
      height: 100%;
      background: rgba(30, 41, 59, 0.5);
      backdrop-filter: blur(10px);
      border-radius: var(--border-radius);
      border: 1px solid rgba(99, 102, 241, 0.2);
      box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
      overflow: hidden;
    }

    .cyber-card {
      position: absolute;
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 2.5rem;
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
      animation: float 8s infinite ease-in-out;
      transition: var(--transition);
      backdrop-filter: blur(5px);
      border: 1px solid rgba(99, 102, 241, 0.3);
      background: rgba(30, 41, 59, 0.7);
    }

    .cyber-card:nth-child(1) {
      width: 120px;
      height: 120px;
      top: 20px;
      left: 30px;
      animation-delay: 0s;
      color: var(--primary-light);
    }

    .cyber-card:nth-child(2) {
      width: 100px;
      height: 100px;
      top: 180px;
      right: 40px;
      animation-delay: 2s;
      color: var(--accent);
    }

    .cyber-card:nth-child(3) {
      width: 140px;
      height: 140px;
      bottom: 30px;
      left: 50px;
      animation-delay: 4s;
      color: var(--success);
    }

    .cyber-card:hover {
      transform: scale(1.1) translateY(-10px);
      box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
    }

    /* Featured Course Section */
    .featured-section {
      max-width: 1400px;
      margin: 80px auto;
      padding: 0 40px;
    }

    .section-title {
      text-align: center;
      margin-bottom: 50px;
      position: relative;
    }

    .section-title h2 {
      font-size: 2.5rem;
      color: var(--primary-light);
      margin-bottom: 15px;
    }

    .section-title p {
      color: var(--neutral-700);
      max-width: 600px;
      margin: 0 auto;
    }

    .section-title::after {
      content: '';
      position: absolute;
      bottom: -15px;
      left: 50%;
      transform: translateX(-50%);
      width: 80px;
      height: 4px;
      background: linear-gradient(to right, var(--primary), var(--accent));
      border-radius: 2px;
    }

    .featured-course {
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      border-radius: var(--border-radius);
      padding: 40px;
      color: white;
      box-shadow: 0 25px 50px rgba(0, 0, 0, 0.3);
      position: relative;
      overflow: hidden;
      animation: pulse 10s infinite ease-in-out;
    }

    .featured-course::before {
      content: '';
      position: absolute;
      top: -50px;
      right: -50px;
      width: 200px;
      height: 200px;
      background: rgba(255, 255, 255, 0.1);
      border-radius: 50%;
    }

    .featured-badge {
      position: absolute;
      top: 25px;
      right: 25px;
      background: var(--neutral-900);
      padding: 8px 20px;
      border-radius: 30px;
      font-size: 0.9rem;
      font-weight: 600;
      color: var(--primary-dark);
      box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    }

    .featured-course h3 {
      font-size: 2.2rem;
      margin-bottom: 20px;
      position: relative;
      z-index: 1;
    }

    .featured-course p {
      margin-bottom: 30px;
      max-width: 700px;
      position: relative;
      z-index: 1;
      opacity: 0.95;
      font-size: 1.1rem;
      line-height: 1.7;
    }

    .featured-course a {
      display: inline-block;
      background: var(--neutral-900);
      color: var(--primary-dark);
      padding: 15px 35px;
      border-radius: 50px;
      text-decoration: none;
      font-weight: 600;
      transition: var(--transition);
      position: relative;
      z-index: 1;
      border: 1px solid transparent;
      box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    }

    .featured-course a:hover {
      transform: translateY(-5px);
      box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
      background: transparent;
      color: var(--neutral-900);
      border-color: var(--neutral-900);
    }

    /* Courses Section */
    .courses-section {
      max-width: 1400px;
      margin: 80px auto;
      padding: 0 40px;
    }

    .courses-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(330px, 1fr));
      gap: 30px;
    }

    .course-card {
      background: rgba(30, 41, 59, 0.7);
      backdrop-filter: blur(10px);
      border-radius: var(--border-radius);
      padding: 30px;
      box-shadow: var(--card-shadow);
      text-align: center;
      min-height: 240px;
      transition: var(--transition);
      border: 1px solid rgba(99, 102, 241, 0.2);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      position: relative;
      overflow: hidden;
    }

    .course-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 5px;
      background: linear-gradient(to right, var(--primary), var(--accent));
      transform: scaleX(0);
      transform-origin: left;
      transition: transform 0.5s ease;
    }

    .course-card:hover::before {
      transform: scaleX(1);
    }

    .course-card:hover {
      transform: translateY(-10px);
      box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
      border-color: rgba(99, 102, 241, 0.4);
    }

    .course-card h3 {
      margin-bottom: 20px;
      color: var(--primary-light);
      font-size: 1.4rem;
      min-height: 70px;
      display: flex;
      align-items: center;
      justify-content: center;
      line-height: 1.4;
    }

    .course-card a {
      display: inline-block;
      padding: 13px 30px;
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      color: white;
      border-radius: 50px;
      text-decoration: none;
      transition: var(--transition);
      border: 1px solid transparent;
      font-weight: 600;
      margin-top: 15px;
      box-shadow: 0 5px 15px rgba(99, 102, 241, 0.3);
    }

    .course-card a:hover {
      background: transparent;
      color: var(--primary-light);
      border-color: var(--primary);
      transform: translateY(-3px);
      box-shadow: 0 8px 20px rgba(99, 102, 241, 0.4);
    }

    .coming-soon {
      opacity: 0.8;
    }

    .coming-soon a {
      background: linear-gradient(135deg, #475569 0%, #64748b 100%) !important;
      cursor: not-allowed;
      box-shadow: 0 5px 15px rgba(100, 116, 139, 0.3) !important;
    }

    .coming-soon a:hover {
      background: linear-gradient(135deg, #475569 0%, #64748b 100%) !important;
      color: white !important;
      border-color: transparent !important;
      transform: none !important;
      cursor: not-allowed;
    }

    /* Footer */
    footer {
      background: linear-gradient(135deg, var(--primary-dark) 0%, var(--accent-dark) 100%);
      color: white;
      text-align: center;
      padding: 40px 20px;
      margin-top: 100px;
      position: relative;
    }

    footer::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 3px;
      background: linear-gradient(to right, var(--primary-light), var(--accent));
    }

    footer p {
      font-size: 1.1rem;
    }

    /* Animations */
    @keyframes float {
      0%, 100% { transform: translateY(0) rotate(0deg); }
      33% { transform: translateY(-20px) rotate(3deg); }
      66% { transform: translateY(10px) rotate(-3deg); }
    }

    @keyframes pulse {
      0%, 100% { transform: scale(1); opacity: 1; }
      50% { transform: scale(1.02); opacity: 0.95; }
    }

    /* Responsive Design */
    @media (max-width: 1200px) {
      .hero {
        flex-direction: column;
        text-align: center;
        gap: 50px;
      }
      
      .hero-stats {
        justify-content: center;
      }
      
      .hero-visual {
        width: 100%;
        max-width: 600px;
      }

      #search-bar:focus {
        width: 280px;
      }
    }

    @media (max-width: 768px) {
      body {
        padding-top: 40px;
      }
      
      nav {
        top: 35px;
        flex-wrap: wrap;
        padding: 15px;
        margin: 0 10px;
      }
      
      .nav-links {
        flex-direction: column;
        width: 100%;
        display: none;
        background: rgba(30, 41, 59, 0.95);
        padding: 20px 0;
        margin-top: 15px;
        gap: 15px;
      }

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

      .menu-toggle {
        display: block;
      }

      #search-bar {
        margin: 15px 0;
        width: 100%;
        order: 1;
      }

      .marquee-container {
        font-size: 0.8rem;
        padding: 0.6rem;
      }

      .hero {
        margin: 60px auto;
        padding: 0 20px;
      }

      .hero-content h1 {
        font-size: 2.8rem;
      }

      .hero-content p {
        font-size: 1.1rem;
      }

      .hero-stats {
        flex-direction: column;
        gap: 30px;
      }

      .featured-section, .courses-section {
        padding: 0 20px;
      }

      .featured-course {
        padding: 30px;
      }
      
      .featured-course h3 {
        font-size: 1.8rem;
      }

      .courses-grid {
        grid-template-columns: 1fr;
        gap: 25px;
      }

      .course-card h3 {
        min-height: auto;
        font-size: 1.3rem;
      }
    }

    @media (max-width: 480px) {
      .hero-content h1 {
        font-size: 2.2rem;
      }

      .featured-course {
        padding: 25px;
      }
      
      .featured-course h3 {
        font-size: 1.5rem;
      }

      .section-title h2 {
        font-size: 2rem;
      }

      .cyber-card {
        width: 80px;
        height: 80px;
        font-size: 2rem;
      }

      .hero-visual {
        height: 300px;
      }
    }

/* Overlay screen */
#overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: #0a0a0a;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "Inter", sans-serif;
  font-size: 1.5rem;
  z-index: 9999;
  transition: opacity 0.6s ease;
}

/* Hide after fade */
#overlay.hidden {
  opacity: 0;
  pointer-events: none;
}