* { box-sizing: border-box; margin: 0; padding: 0; }
    html { scroll-behavior: smooth; }
    body {
      font-family: 'Poppins', sans-serif;
      color: #fff;
      line-height: 1.6;
      background: url('https://noticias.unsam.edu.ar/wp-content/uploads/2019/02/lsaweb-01.jpg') center/cover no-repeat fixed;
    }

    nav {
      position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
      background: rgba(0,0,0,0.2); backdrop-filter: blur(10px);
      border-bottom: 1px solid rgba(255,255,255,0.1);
      padding: 15px 20px;
      display: flex; justify-content: space-between; align-items: center;
      transition: all 0.3s ease;
    }

    .nav-logo { display: flex; align-items: center; gap: 10px; }
    .nav-logo img { width: 50px; height: 50px; border-radius: 50%; }
    .nav-logo span { font-weight: 600; font-size: 1.2rem; display: none; }

    nav ul { list-style: none; display: flex; gap: 30px; margin: 0; }
    nav ul li a {
      color: #fff; text-decoration: none; font-size: 1rem; font-weight: 500;
      transition: all 0.3s ease; padding: 8px 16px; border-radius: 20px;
    }
    nav ul li a:hover { background: rgba(30, 79, 159, 0.3); color: #fff; }

    .menu-toggle { display: none; flex-direction: column; cursor: pointer; padding: 5px; }
    .menu-toggle span { width: 25px; height: 3px; background: #fff; margin: 3px 0; transition: 0.3s; border-radius: 2px; }

    main {
      min-height: 100vh;
      padding: 120px 20px 60px;
      position: relative;
    }

    .hero-section {
      text-align: center;
      margin-bottom: 80px;
    }

    .hero-title {
      font-size: clamp(2.2rem, 5vw, 3.5rem);
      margin-bottom: 20px;
      color: #5a99ff;
      font-weight: 700;
      background: rgba(0,0,0,0.75);
      padding: 30px;
      border-radius: 20px;
      box-shadow: 0 10px 30px rgba(0,0,0,0.3);
      max-width: 800px;
      margin: 0 auto 80px;
    }

    .learning-section {
      display: flex;
      align-items: center;
      gap: 40px;
      margin-bottom: 80px;
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      margin-bottom: 80px;
    }

    .learning-section.reverse {
      flex-direction: row-reverse;
    }

    .content-box {
      flex: 1;
      background: rgba(0,0,0,0.75);
      border-radius: 20px;
      padding: 40px 30px;
      box-shadow: 0 10px 30px rgba(0,0,0,0.3);
    }

    .content-box h2 {
      color: #5a99ff;
      margin-bottom: 20px;
      font-size: 1.8rem;
      font-weight: 600;
    }

    .content-box h3 {
      color: #fff;
      margin-bottom: 15px;
      font-size: 1.3rem;
      font-weight: 600;
    }

    .content-box p {
      color: #fff;
      font-size: 1.1rem;
      margin-bottom: 15px;
      opacity: 0.93;
    }

    .content-box ul {
      color: #fff;
      margin-left: 20px;
      margin-bottom: 15px;
    }

    .content-box li {
      margin-bottom: 8px;
      opacity: 0.93;
    }

    .image-box {
      flex: 1;
      background: rgba(0,0,0,0.75);
      border-radius: 20px;
      padding: 20px;
      box-shadow: 0 10px 30px rgba(0,0,0,0.3);
      display: flex;
      align-items: center;
      justify-content: center;
      min-height: 300px;
    }

    .image-box img {
      width: 100%;
      height: auto;
      border-radius: 15px;
      object-fit: cover;
      max-height: 280px;
    }

    .placeholder-image {
      width: 100%;
      height: 280px;
      background: linear-gradient(135deg, #5a99ff, #1e4f9f);
      border-radius: 15px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-size: 1.2rem;
      text-align: center;
      font-weight: 600;
    }

    footer {
      background: rgba(0,0,0,0.8);
      backdrop-filter: blur(10px);
      border-top: 1px solid rgba(255,255,255,0.1);
      padding: 30px 20px;
    }

    .footer-content { 
      display: flex; 
      justify-content: space-between; 
      align-items: center; 
      max-width: 1200px; 
      margin: 0 auto; 
      flex-wrap: wrap; 
      gap: 20px; 
    }

    .logo-footer { display: flex; align-items: center; gap: 10px; }
    .logo-footer img { width: 40px; height: 40px; border-radius: 50%; }
    .logo-footer span { font-weight: 600; font-size: 1.1rem; }

    .footer-links { display: flex; gap: 20px; }
    .footer-links a { color: #fff; text-decoration: none; opacity: 0.9; transition: 0.3s; }
    .footer-links a:hover { color: #5a99ff; }

    .copyright { 
      text-align: center; 
      margin-top: 20px; 
      padding-top: 20px; 
      border-top: 1px solid rgba(255,255,255,0.1); 
      color: rgba(255,255,255,0.7); 
      font-size: 0.9rem; 
    }

    @media (max-width: 768px) {
      nav ul { 
        position: fixed; 
        top: 80px; 
        left: -100%; 
        width: 100%; 
        height: calc(100vh - 80px); 
        background: rgba(0,0,0,0.95); 
        flex-direction: column; 
        align-items: center; 
        gap: 30px; 
        padding-top: 40px; 
        transition: left 0.3s; 
      }
      nav ul.active { left: 0; }
      .menu-toggle { display: flex; }
      
      .learning-section,
      .learning-section.reverse {
        flex-direction: column;
        gap: 30px;
      }
      
      .content-box,
      .image-box {
        padding: 25px 20px;
      }
      
      .footer-content { flex-direction: column; text-align: center; }
      .footer-links { justify-content: center; }
    }

    @media (max-width: 480px) {
      main { padding: 80px 10px 40px; }
      .content-box,
      .image-box { padding: 20px 15px; }
      .hero-title { padding: 20px 15px; }
    }