/* =====================================================
   LANDING PAGE — CASD ACADEMIC v4.0
   PALETA INSTITUCIONAL: ROJO OSCURO · GRIS CLARO · BLANCO
   ===================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

:root {
    --rojo: #8B1A1A;
    --rojo-rgb: 139, 26, 26;
    --rojo-hover: #6d1414;
    --rojo-light: #a82828;
    --white: #ffffff;
    --gray-50: #fafbfc;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    --border-color: #e5e7eb;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--white);
    color: var(--gray-900);
    overflow: hidden;
    height: 100vh;
    width: 100vw;
    -webkit-font-smoothing: antialiased;
}

::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--gray-300); border-radius: 10px; }

/* ═══════════════════════════════════════════════════════
   NAVBAR
   ═══════════════════════════════════════════════════════ */
.landing-nav {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 100;
    padding: 18px 40px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: 0.3s;
    background: transparent;
}

.landing-nav.scrolled {
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    padding: 12px 40px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.06);
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
}

.nav-brand img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 2px solid rgba(var(--rojo-rgb), 0.2);
    padding: 2px;
    background: white;
}

.nav-brand span {
    font-weight: 800;
    font-size: 1rem;
    letter-spacing: 1.5px;
    color: var(--gray-900);
}

.landing-nav:not(.scrolled) .nav-brand span {
    color: var(--white);
}

.nav-cta {
    background: var(--rojo);
    border: none;
    color: var(--white);
    padding: 10px 24px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.85rem;
    text-decoration: none;
    transition: 0.3s;
    font-family: 'Inter', sans-serif;
    box-shadow: 0 4px 14px rgba(var(--rojo-rgb), 0.25);
}

.nav-cta:hover {
    background: var(--rojo-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(var(--rojo-rgb), 0.35);
    color: var(--white);
}

.landing-nav:not(.scrolled) .nav-cta {
    background: rgba(255,255,255, 0.15);
    border: 1px solid rgba(255,255,255,0.3);
    backdrop-filter: blur(4px);
    box-shadow: none;
}

.landing-nav:not(.scrolled) .nav-cta:hover {
    background: var(--white);
    color: var(--rojo);
    border-color: var(--white);
}

/* ═══════════════════════════════════════════════════════
   HERO SECTION
   ═══════════════════════════════════════════════════════ */
.hero {
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 40px 20px 100px;
    position: relative;
    background: linear-gradient(170deg, var(--rojo) 0%, var(--rojo-hover) 40%, #4a0e0e 100%);
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 120px;
    background: var(--white);
    clip-path: ellipse(55% 100% at 50% 100%);
}

/* Decorative shapes */
.hero-decor {
    position: absolute;
    border-radius: 50%;
    background: rgba(255,255,255,0.04);
    pointer-events: none;
}

.hero-decor-1 {
    width: 500px;
    height: 500px;
    top: -150px;
    right: -150px;
    animation: floatSlow 20s infinite ease-in-out alternate;
}

.hero-decor-2 {
    width: 350px;
    height: 350px;
    bottom: 50px;
    left: -100px;
    animation: floatSlow 25s infinite ease-in-out alternate-reverse;
}

.hero-decor-3 {
    width: 200px;
    height: 200px;
    top: 30%;
    right: 15%;
    background: rgba(255,255,255,0.03);
    animation: floatSlow 15s infinite ease-in-out alternate;
}

@keyframes floatSlow {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(30px, 40px) scale(1.05); }
}

.hero-logo {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    border: 3px solid rgba(255, 255, 255, 0.3);
    padding: 4px;
    margin-bottom: 28px;
    background: rgba(255,255,255,0.1);
    backdrop-filter: blur(8px);
    box-shadow: 0 8px 32px rgba(0,0,0,0.2);
    animation: logoFloat 3s infinite ease-in-out;
}

@keyframes logoFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 7px 18px;
    border-radius: 50px;
    background: rgba(255,255,255,0.1);
    border: 1px solid rgba(255,255,255,0.15);
    font-size: 0.8rem;
    color: rgba(255,255,255,0.8);
    margin-bottom: 24px;
    font-weight: 500;
    backdrop-filter: blur(4px);
}

.hero-badge i {
    color: rgba(255,255,255,0.5);
    font-size: 0.55rem;
}

.hero h1 {
    font-size: clamp(4.5rem, 13vw, 9.5rem);
    font-weight: 900;
    margin: 0 0 20px;
    line-height: 1.1;
    letter-spacing: -0.5px;
    color: var(--white);
}

.hero h1 .highlight {
    position: relative;
    display: inline-block;
}

.hero h1 .highlight::after {
    content: '';
    position: absolute;
    bottom: 4px;
    left: 0;
    right: 0;
    height: 8px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    z-index: -1;
}

.hero p {
    font-size: 1.1rem;
    color: rgba(255,255,255,0.7);
    max-width: 520px;
    line-height: 1.7;
    margin: 0 auto 36px;
}

.hero-cta {
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
    justify-content: center;
}

.btn-hero-primary {
    background: var(--white);
    color: var(--rojo);
    padding: 15px 36px;
    border-radius: 50px;
    font-weight: 700;
    font-size: 0.95rem;
    text-decoration: none;
    transition: 0.3s;
    border: none;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
    font-family: 'Inter', sans-serif;
}

.btn-hero-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 35px rgba(0, 0, 0, 0.2);
    color: var(--rojo-hover);
}

.btn-hero-secondary {
    background: transparent;
    border: 2px solid rgba(255,255,255,0.3);
    color: var(--white);
    padding: 14px 32px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.95rem;
    text-decoration: none;
    transition: 0.3s;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-family: 'Inter', sans-serif;
}

.btn-hero-secondary:hover {
    background: rgba(255,255,255,0.1);
    border-color: rgba(255,255,255,0.5);
    color: var(--white);
}

/* ═══════════════════════════════════════════════════════
   STATS SECTION
   ═══════════════════════════════════════════════════════ */
.stats-bar {
    display: flex;
    justify-content: center;
    gap: 80px;
    padding: 60px 20px 40px;
    max-width: 800px;
    margin: 0 auto;
    flex-wrap: wrap;
}

.stat-item {
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 900;
    display: block;
    color: var(--rojo);
    line-height: 1;
    margin-bottom: 6px;
}

.stat-label {
    font-size: 0.82rem;
    color: var(--gray-500);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1.5px;
}

/* ═══════════════════════════════════════════════════════
   FEATURES
   ═══════════════════════════════════════════════════════ */
.features-section {
    padding: 60px 20px 100px;
    max-width: 1100px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 56px;
}

.section-header .label {
    display: inline-block;
    padding: 6px 16px;
    border-radius: 50px;
    background: rgba(var(--rojo-rgb), 0.08);
    color: var(--rojo);
    font-weight: 700;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 14px;
}

.section-header h2 {
    font-size: 2rem;
    font-weight: 800;
    margin: 0 0 10px;
    color: var(--gray-900);
}

.section-header p {
    color: var(--gray-500);
    max-width: 480px;
    margin: 0 auto;
    font-size: 0.95rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
}

.feature-card {
    background: var(--white);
    border: 1px solid var(--border-color);
    padding: 32px;
    border-radius: 20px;
    transition: 0.3s;
    position: relative;
    box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.feature-card:hover {
    border-color: rgba(var(--rojo-rgb), 0.2);
    transform: translateY(-5px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.08);
}

.feature-icon {
    width: 52px;
    height: 52px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 18px;
    font-size: 1.3rem;
    transition: 0.3s;
}

.feature-icon.red {
    background: rgba(var(--rojo-rgb), 0.08);
    color: var(--rojo);
}

.feature-icon.gray {
    background: var(--gray-100);
    color: var(--gray-600);
}

.feature-icon.dark {
    background: var(--gray-800);
    color: var(--white);
}

.feature-card:hover .feature-icon {
    transform: scale(1.08);
}

.feature-card h3 {
    font-size: 1.1rem;
    font-weight: 700;
    margin: 0 0 8px;
    color: var(--gray-900);
}

.feature-card p {
    color: var(--gray-500);
    line-height: 1.6;
    margin: 0;
    font-size: 0.9rem;
}

/* ═══════════════════════════════════════════════════════
   HOW IT WORKS
   ═══════════════════════════════════════════════════════ */
.steps-section {
    padding: 80px 20px 100px;
    max-width: 900px;
    margin: 0 auto;
    background: var(--gray-50);
    border-radius: 0;
}

.steps-bg {
    background: var(--gray-50);
    padding: 1px 0;
}

.steps-list {
    display: flex;
    flex-direction: column;
    gap: 0;
    position: relative;
}

.steps-list::before {
    content: '';
    position: absolute;
    left: 28px;
    top: 35px;
    bottom: 35px;
    width: 2px;
    background: linear-gradient(180deg, var(--rojo), var(--gray-300));
    opacity: 0.4;
}

.step-item {
    display: flex;
    gap: 20px;
    align-items: flex-start;
    padding: 20px 0;
    position: relative;
}

.step-number {
    width: 56px;
    height: 56px;
    min-width: 56px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    font-size: 1.1rem;
    background: var(--rojo);
    color: var(--white);
    box-shadow: 0 4px 14px rgba(var(--rojo-rgb), 0.25);
    z-index: 1;
}

.step-content h4 {
    font-weight: 700;
    font-size: 1.05rem;
    margin: 6px 0 4px;
    color: var(--gray-900);
}

.step-content p {
    color: var(--gray-500);
    margin: 0;
    font-size: 0.9rem;
}

/* ═══════════════════════════════════════════════════════
   FOOTER
   ═══════════════════════════════════════════════════════ */
.simple-footer {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 24px 20px;
    text-align: center;
    background: transparent;
    z-index: 10;
}

.simple-footer p {
    color: var(--gray-400);
    font-size: 0.82rem;
    margin: 0;
}

.footer-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-bottom: 10px;
}

.footer-brand img {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    opacity: 0.7;
}

.footer-brand span {
    font-weight: 700;
    font-size: 0.85rem;
    color: var(--rojo);
    letter-spacing: 1.5px;
}

/* ═══════════════════════════════════════════════════════
   ANIMATIONS
   ═══════════════════════════════════════════════════════ */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

.animate-in {
    animation: heroFadeIn 0.7s ease-out forwards;
}

@keyframes heroFadeIn {
    from { opacity: 0; transform: translateY(24px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ═══════════════════════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════════════════════ */
@media (max-width: 768px) {
    .landing-nav { padding: 14px 20px; }
    .nav-brand span { font-size: 0.85rem; letter-spacing: 1px; }
    .stats-bar { gap: 40px; }
    .stat-number { font-size: 2rem; }
    .steps-list::before { display: none; }
    .step-number { width: 44px; height: 44px; min-width: 44px; font-size: 0.95rem; }
    .hero-logo { width: 80px; height: 80px; }
    .hero { padding-bottom: 120px; }
}