:root {
    --primary: #2e7d32;
    --primary-light: #4caf50;
    --accent: #ff9800;
    --bg: #0a0a0a;
    --bg-card: #161616;
    --text: #ffffff;
    --text-gray: #b0b0b0;
    --border: rgba(255,255,255,0.08);
    
    /* Responsive Font Sizes */
    --fs-h1: 2.2rem;
    --fs-h2: 1.8rem;
    --fs-base: 0.95rem;
}

@media (min-width: 768px) {
    :root {
        --fs-h1: 3.5rem;
        --fs-h2: 2.5rem;
        --fs-base: 1rem;
    }
}

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

body {
    font-family: 'Inter', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    font-size: var(--fs-base);
    overflow-x: hidden;
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 1.5rem; }

/* Header & Nav */
.header {
    position: fixed;
    top: 0; width: 100%;
    background: rgba(10, 10, 10, 0.9);
    backdrop-filter: blur(12px);
    z-index: 1000;
    border-bottom: 1px solid var(--border);
    transition: 0.3s;
}

.nav { height: 70px; display: flex; align-items: center; justify-content: space-between; }
.logo { height: 40px; }

/* Menú Móvil */
.nav-toggle {
    display: flex; flex-direction: column; gap: 6px;
    background: none; z-index: 1100;
}

.nav-toggle span {
    width: 28px; height: 3px; background: var(--text);
    border-radius: 4px; transition: 0.3s;
}

.nav-toggle.active span:nth-child(1) { transform: translateY(9px) rotate(45deg); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: translateY(-9px) rotate(-45deg); }

.nav-links {
    position: fixed; top: 0; right: -100%;
    width: 80%; height: 100vh;
    background: var(--bg-card);
    display: flex; flex-direction: column;
    justify-content: center; align-items: center;
    gap: 2.5rem; transition: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.nav-links.active { right: 0; box-shadow: -10px 0 30px rgba(0,0,0,0.5); }

@media (min-width: 768px) {
    .nav-toggle { display: none; }
    .nav-links {
        position: static; width: auto; height: auto;
        flex-direction: row; background: none;
    }
}

.nav-link { font-weight: 600; color: var(--text-gray); transition: 0.3s; }
.nav-link:hover { color: var(--primary-light); }

/* Hero */
.hero {
    padding: 140px 0 80px;
    background: linear-gradient(rgba(0,0,0,0.7), rgba(0,0,0,0.7)), url('https://images.unsplash.com/photo-1500382017468-9049fed747ef?q=80&w=1500') center/cover;
    text-align: center;
}

.hero h1 { font-size: var(--fs-h1); font-weight: 800; margin-bottom: 1.5rem; line-height: 1.1; }
.accent { color: var(--primary-light); }
.hero-badge {
    display: inline-flex; align-items: center; gap: 8px;
    background: rgba(255,255,255,0.1); padding: 8px 16px;
    border-radius: 50px; font-size: 0.8rem; margin-bottom: 1.5rem;
}

.hero-buttons { display: flex; gap: 15px; justify-content: center; flex-wrap: wrap; }
.btn { padding: 12px 28px; border-radius: 50px; font-weight: 700; text-decoration: none; transition: 0.3s; }
.btn-primary { background: var(--primary); color: white; }
.btn-outline { border: 1px solid var(--text-gray); color: white; }

/* Cards */
.courses-grid { display: grid; gap: 30px; margin-top: 40px; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }

.course-card {
    background: var(--bg-card); border-radius: 15px;
    overflow: hidden; border: 1px solid var(--border);
    transition: 0.3s; position: relative;
}

.course-card:hover { transform: translateY(-10px); border-color: var(--primary); }

.course-image { height: 200px; position: relative; cursor: pointer; }
.course-image img { width: 100%; height: 100%; object-fit: cover; }

.image-overlay {
    position: absolute; inset: 0; background: rgba(0,0,0,0.5);
    display: flex; flex-direction: column; align-items: center;
    justify-content: center; opacity: 0; transition: 0.3s;
}

.course-image:hover .image-overlay { opacity: 1; }

.course-content { padding: 20px; }
.badge { padding: 4px 12px; border-radius: 4px; font-size: 0.7rem; font-weight: 800; }
.badge-new { background: var(--primary); }

.btn-cert {
    width: 100%; padding: 14px; background: var(--primary);
    border: none; color: white; border-radius: 8px;
    font-weight: 700; margin-top: 20px; cursor: pointer;
}

/* Modal Lightbox */
.modal {
    position: fixed; inset: 0; background: rgba(0,0,0,0.95);
    z-index: 2000; display: none; align-items: center; justify-content: center;
}

.modal.active { display: flex; }
.modal img { max-width: 90%; max-height: 80vh; border-radius: 8px; }
.modal-close { position: absolute; top: 20px; right: 30px; font-size: 40px; color: white; cursor: pointer; }

/* WhatsApp */
.whatsapp-btn {
    position: fixed; bottom: 25px; right: 25px;
    width: 60px; height: 60px; background: #25d366;
    border-radius: 50%; display: flex; align-items: center;
    justify-content: center; font-size: 30px; color: white;
    box-shadow: 0 10px 20px rgba(0,0,0,0.3); z-index: 999;
}