/* ============================================
   Sky Education Colombia - Premium Styles
   Diseño institucional, moderno y elegante
   ============================================ */

:root {
    /* Colors */
    --primary: #0B1426;
    --primary-light: #141E33;
    --accent: #C9A227;
    --accent-soft: #E8D48B;
    --white: #FFFFFF;
    --off-white: #F8F9FC;
    --gray-100: #F1F3F7;
    --gray-200: #E2E6EF;
    --gray-400: #9AA3B5;
    --gray-600: #5A6577;
    --gray-800: #2A3344;
    --text: #1A2332;
    
    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-serif: 'Playfair Display', Georgia, serif;
    
    /* Spacing */
    --section-padding: clamp(4rem, 8vw, 7rem);
    --container: min(1120px, 92vw);
    
    /* Effects */
    --radius: 16px;
    --radius-sm: 10px;
    --shadow: 0 4px 24px rgba(11, 20, 38, 0.08);
    --shadow-lg: 0 20px 60px rgba(11, 20, 38, 0.12);
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-sans);
    color: var(--text);
    background: var(--white);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

img {
    max-width: 100%;
    display: block;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

ul {
    list-style: none;
}

button {
    border: none;
    background: none;
    cursor: pointer;
    font-family: inherit;
}

.container {
    width: var(--container);
    margin: 0 auto;
}

/* Progress Bar */
.progress-bar {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), var(--accent-soft));
    width: 0%;
    z-index: 9999;
    transition: width 0.1s linear;
}

/* ========== NAVBAR ========== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 1.25rem 0;
    transition: var(--transition);
}

.navbar.scrolled {
    background: rgba(11, 20, 38, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 0.85rem 0;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.15);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    color: var(--white);
    font-weight: 600;
}

.logo-icon {
    font-size: 1.5rem;
    color: var(--accent);
}

.logo-text {
    font-size: 1.1rem;
    letter-spacing: -0.02em;
}

.logo-text span {
    display: block;
    font-size: 0.7rem;
    font-weight: 400;
    opacity: 0.7;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    color: rgba(255, 255, 255, 0.85);
    font-size: 0.9rem;
    font-weight: 500;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: var(--transition);
}

.nav-links a:hover {
    color: var(--white);
}

.nav-links a:hover::after {
    width: 100%;
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 4px;
}

.menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--white);
    transition: var(--transition);
    border-radius: 2px;
}

/* ========== HERO ========== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: 
        linear-gradient(135deg, rgba(11, 20, 38, 0.85) 0%, rgba(11, 20, 38, 0.7) 100%),
        url('https://images.unsplash.com/photo-1436491865332-7a61a109cc05?auto=format&fit=crop&w=1920&q=80') center/cover no-repeat;
    color: var(--white);
    text-align: center;
    padding: 6rem 1.5rem 4rem;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: radial-gradient(ellipse at center, transparent 0%, rgba(11, 20, 38, 0.4) 100%);
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 780px;
}

.hero-badge {
    display: inline-block;
    padding: 0.4rem 1.2rem;
    background: rgba(201, 162, 39, 0.15);
    border: 1px solid rgba(201, 162, 39, 0.4);
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 500;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--accent-soft);
    margin-bottom: 1.5rem;
}

.hero h1 {
    font-family: var(--font-serif);
    font-size: clamp(2.4rem, 5.5vw, 3.8rem);
    font-weight: 700;
    line-height: 1.15;
    margin-bottom: 1.25rem;
    letter-spacing: -0.02em;
}

.hero h1 span {
    color: var(--accent);
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.2rem);
    color: rgba(255, 255, 255, 0.8);
    max-width: 560px;
    margin: 0 auto 2.5rem;
    font-weight: 300;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.9rem 2rem;
    border-radius: 50px;
    font-size: 0.95rem;
    font-weight: 600;
    transition: var(--transition);
}

.btn-primary {
    background: var(--accent);
    color: var(--primary);
}

.btn-primary:hover {
    background: var(--accent-soft);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(201, 162, 39, 0.35);
}

.btn-secondary {
    background: transparent;
    color: var(--white);
    border: 1.5px solid rgba(255, 255, 255, 0.4);
}

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

.hero-scroll {
    position: absolute;
    bottom: 2.5rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.75rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.scroll-line {
    width: 1px;
    height: 40px;
    background: linear-gradient(to bottom, rgba(255,255,255,0.5), transparent);
    animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
    0%, 100% { opacity: 0.4; transform: scaleY(1); }
    50% { opacity: 1; transform: scaleY(1.1); }
}

/* ========== INTRO ========== */
.intro {
    padding: var(--section-padding) 0;
    background: var(--off-white);
}

.intro-grid {
    display: grid;
    grid-template-columns: 1.4fr 1fr;
    gap: 4rem;
    align-items: center;
}

.intro-text h2 {
    font-family: var(--font-serif);
    font-size: clamp(1.8rem, 3.5vw, 2.4rem);
    margin-bottom: 1.25rem;
    color: var(--primary);
}

.intro-text p {
    color: var(--gray-600);
    margin-bottom: 1rem;
    font-size: 1.05rem;
}

.intro-card {
    background: var(--primary);
    color: var(--white);
    padding: 2.5rem;
    border-radius: var(--radius);
    display: flex;
    flex-direction: column;
    gap: 2rem;
    box-shadow: var(--shadow-lg);
}

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

.intro-stat .number {
    display: block;
    font-size: 2.8rem;
    font-weight: 700;
    color: var(--accent);
    line-height: 1;
}

.intro-stat .label {
    font-size: 0.9rem;
    opacity: 0.8;
    margin-top: 0.4rem;
    display: block;
}

/* ========== SECTION HEADER ========== */
.section-header {
    text-align: center;
    max-width: 640px;
    margin: 0 auto 3.5rem;
}

.section-header.light {
    color: var(--white);
}

.section-label {
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 0.75rem;
}

.section-header h2 {
    font-family: var(--font-serif);
    font-size: clamp(1.9rem, 3.5vw, 2.6rem);
    color: var(--primary);
    margin-bottom: 0.75rem;
    letter-spacing: -0.02em;
}

.section-header.light h2 {
    color: var(--white);
}

.section-desc {
    color: var(--gray-600);
    font-size: 1.05rem;
}

.section-header.light .section-desc {
    color: rgba(255, 255, 255, 0.7);
}

/* ========== TOPICS / CARDS ========== */
.topics {
    padding: var(--section-padding) 0;
}

.cards-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.card {
    background: var(--white);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 2rem 1.75rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: var(--transition);
}

.card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}

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

.card-icon {
    font-size: 2rem;
    margin-bottom: 1.25rem;
}

.card h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--primary);
}

.card p {
    font-size: 0.95rem;
    color: var(--gray-600);
    line-height: 1.65;
}

/* ========== STATS ========== */
.stats {
    padding: var(--section-padding) 0;
    background: var(--primary);
    color: var(--white);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
    text-align: center;
}

.stat-item {
    padding: 1.5rem 1rem;
}

.stat-number {
    font-size: clamp(2.2rem, 4vw, 3.2rem);
    font-weight: 700;
    color: var(--accent);
    line-height: 1;
}

.stat-plus {
    font-size: 1.4rem;
    color: var(--accent-soft);
    font-weight: 600;
}

.stat-item p {
    margin-top: 0.75rem;
    font-size: 0.9rem;
    opacity: 0.75;
}

.stats-note {
    text-align: center;
    margin-top: 2.5rem;
    font-size: 0.8rem;
    opacity: 0.5;
}

/* ========== PROCESS / TIMELINE ========== */
.process {
    padding: var(--section-padding) 0;
    background: var(--off-white);
}

.timeline {
    max-width: 700px;
    margin: 0 auto;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 28px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--gray-200);
}

.timeline-item {
    display: flex;
    gap: 2rem;
    margin-bottom: 2.5rem;
    position: relative;
}

.timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-marker {
    width: 56px;
    height: 56px;
    background: var(--primary);
    color: var(--accent);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.95rem;
    flex-shrink: 0;
    z-index: 1;
    box-shadow: 0 0 0 6px var(--off-white);
}

.timeline-content {
    background: var(--white);
    padding: 1.5rem 1.75rem;
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow);
    flex: 1;
}

.timeline-content h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    color: var(--primary);
}

.timeline-content p {
    font-size: 0.95rem;
    color: var(--gray-600);
}

/* ========== FAQ ========== */
.faq {
    padding: var(--section-padding) 0;
}

.faq-list {
    max-width: 720px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid var(--gray-200);
}

.faq-question {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.4rem 0;
    font-size: 1.05rem;
    font-weight: 500;
    color: var(--primary);
    text-align: left;
}

.faq-icon {
    font-size: 1.4rem;
    color: var(--accent);
    transition: var(--transition);
    font-weight: 300;
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.35s ease, padding 0.35s ease;
}

.faq-item.active .faq-answer {
    max-height: 300px;
    padding-bottom: 1.4rem;
}

.faq-answer p {
    color: var(--gray-600);
    font-size: 0.98rem;
    line-height: 1.7;
}

/* ========== TESTIMONIALS ========== */
.testimonials {
    padding: var(--section-padding) 0;
    background: var(--white);
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.75rem;
}

.testimonial-card {
    background: var(--off-white);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 2.25rem 1.75rem 1.75rem;
    position: relative;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.testimonial-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
    background: var(--white);
}

.testimonial-quote {
    font-family: var(--font-serif);
    font-size: 4rem;
    line-height: 1;
    color: var(--accent);
    opacity: 0.35;
    position: absolute;
    top: 1.1rem;
    left: 1.4rem;
    pointer-events: none;
}

.testimonial-text {
    font-size: 0.98rem;
    color: var(--gray-600);
    line-height: 1.7;
    margin-bottom: 1.75rem;
    flex: 1;
    position: relative;
    z-index: 1;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 0.9rem;
    margin-top: auto;
}

.author-avatar {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--primary);
    color: var(--accent);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.85rem;
    flex-shrink: 0;
}

.author-info strong {
    display: block;
    font-size: 0.95rem;
    color: var(--primary);
    font-weight: 600;
}

.author-info span {
    font-size: 0.8rem;
    color: var(--gray-400);
}

/* ========== ABOUT ========== */
.about {
    padding: var(--section-padding) 0;
    background: var(--off-white);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3.5rem;
    align-items: start;
}

.about-content h2 {
    font-family: var(--font-serif);
    font-size: clamp(1.8rem, 3vw, 2.4rem);
    margin-bottom: 1.25rem;
    color: var(--primary);
}

.about-content p {
    color: var(--gray-600);
    margin-bottom: 1rem;
    font-size: 1.05rem;
}

.about-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 2.25rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--gray-200);
}

.about-card h3 {
    font-size: 0.8rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 1.5rem;
    font-weight: 600;
}

.about-info .name {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 0.25rem;
}

.about-info .role {
    font-size: 0.9rem;
    color: var(--gray-600);
    margin-bottom: 1.75rem;
}

.info-item {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.25rem;
}

.info-item:last-child {
    margin-bottom: 0;
}

.info-icon {
    font-size: 1.1rem;
    margin-top: 2px;
}

.info-item strong {
    display: block;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--gray-400);
    margin-bottom: 0.2rem;
}

.info-item p {
    font-size: 0.95rem;
    color: var(--text);
    line-height: 1.5;
}

.info-item a {
    color: var(--primary);
}

.info-item a:hover {
    color: var(--accent);
}

/* ========== SOURCES ========== */
.sources {
    padding: var(--section-padding) 0;
}

.sources-list {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
}

.source-item {
    padding: 0.75rem 1.5rem;
    background: var(--gray-100);
    border-radius: 50px;
    font-size: 0.9rem;
    color: var(--gray-600);
    font-weight: 500;
}

/* ========== FOOTER ========== */
.footer {
    background: var(--primary);
    color: var(--white);
    padding: 4rem 0 2rem;
}

.footer-top {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
    padding-bottom: 3rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand .logo {
    margin-bottom: 1rem;
}

.footer-brand p {
    font-size: 0.95rem;
    opacity: 0.7;
    max-width: 280px;
    line-height: 1.6;
}

.footer-links h4,
.footer-contact h4 {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 1.25rem;
    color: var(--accent);
}

.footer-links a {
    display: block;
    font-size: 0.95rem;
    opacity: 0.75;
    margin-bottom: 0.6rem;
}

.footer-links a:hover {
    opacity: 1;
    color: var(--accent);
}

.footer-contact p {
    font-size: 0.95rem;
    opacity: 0.75;
    margin-bottom: 0.4rem;
}

.footer-bottom {
    text-align: center;
}

.footer-bottom p {
    font-size: 0.85rem;
    opacity: 0.55;
}

.footer-responsible {
    margin-top: 0.5rem;
    font-size: 0.8rem !important;
}

/* ========== BACK TO TOP ========== */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    background: var(--primary);
    color: var(--accent);
    border-radius: 50%;
    font-size: 1.3rem;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 100;
    box-shadow: var(--shadow-lg);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--accent);
    color: var(--primary);
    transform: translateY(-3px);
}

/* ========== ANIMATIONS ========== */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========== RESPONSIVE ========== */
@media (max-width: 960px) {
    .cards-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .testimonials-grid {
        grid-template-columns: 1fr;
        max-width: 520px;
        margin: 0 auto;
    }
    
    .intro-grid,
    .about-grid {
        grid-template-columns: 1fr;
        gap: 2.5rem;
    }
    
    .footer-top {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 720px) {
    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: var(--primary);
        flex-direction: column;
        padding: 6rem 2rem 2rem;
        gap: 1.5rem;
        transition: right 0.35s ease;
        box-shadow: -10px 0 40px rgba(0,0,0,0.3);
    }
    
    .nav-links.active {
        right: 0;
    }
    
    .menu-toggle {
        display: flex;
        z-index: 1001;
    }
    
    .menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }
    
    .cards-grid {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: 1fr 1fr;
        gap: 1.5rem;
    }
    
    .footer-top {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .timeline::before {
        left: 20px;
    }
    
    .timeline-marker {
        width: 42px;
        height: 42px;
        font-size: 0.8rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 260px;
    }
}

@media (max-width: 480px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }
}