/* ========================================
   MATEMÁTICAS EN LA VIDA - Estilos
   ======================================== */

/* --- Variables --- */
:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --secondary: #7c3aed;
    --accent: #06b6d4;
    --dark: #0f172a;
    --dark-soft: #1e293b;
    --gray: #64748b;
    --gray-light: #94a3b8;
    --light: #f1f5f9;
    --white: #ffffff;
    --success: #10b981;
    --whatsapp: #25d366;
    --gradient: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);
    --radius: 12px;
    --radius-lg: 16px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--dark);
    line-height: 1.6;
    background: var(--white);
    -webkit-font-smoothing: antialiased;
}

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

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

/* --- Container --- */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* --- Navbar --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0,0,0,0.05);
    transition: var(--transition);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--dark);
}

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--gradient);
    color: white;
    border-radius: 10px;
    font-size: 1.5rem;
    font-weight: 800;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--gray);
    transition: var(--transition);
}

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

.btn-nav {
    background: var(--gradient) !important;
    color: var(--white) !important;
    padding: 10px 24px !important;
    border-radius: 50px !important;
    font-weight: 600 !important;
}

.btn-nav:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.4);
}

/* Mobile menu toggle */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

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

/* --- Hero --- */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: var(--gradient);
    overflow: hidden;
    padding-top: 72px;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(circle at 20% 50%, rgba(255,255,255,0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255,255,255,0.08) 0%, transparent 40%);
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 60px 0;
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 800;
    color: var(--white);
    margin-bottom: 20px;
    letter-spacing: -0.02em;
    line-height: 1.1;
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.35rem);
    color: rgba(255, 255, 255, 0.9);
    max-width: 600px;
    margin: 0 auto 40px;
    font-weight: 400;
    line-height: 1.6;
}

.hero-cta {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.hero-wave {
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    z-index: 3;
}

.hero-wave svg {
    display: block;
    width: 100%;
    height: auto;
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    font-family: inherit;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(37, 99, 235, 0.4);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.15);
    color: var(--white);
    border: 2px solid rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.25);
    border-color: rgba(255, 255, 255, 0.5);
}

.btn-whatsapp {
    background: var(--whatsapp);
    color: var(--white);
}

.btn-whatsapp:hover {
    background: #20bd5a;
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(37, 211, 102, 0.4);
}

.btn-github {
    background: var(--dark);
    color: var(--white);
}

.btn-github:hover {
    background: var(--dark-soft);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(15, 23, 42, 0.4);
}

.btn-block {
    width: 100%;
    justify-content: center;
}

/* --- Sections --- */
.section {
    padding: 100px 0;
}

.section-badge {
    display: inline-block;
    background: var(--light);
    color: var(--primary);
    padding: 8px 20px;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.section-title {
    font-size: clamp(1.8rem, 4vw, 2.75rem);
    font-weight: 800;
    color: var(--dark);
    margin-bottom: 16px;
    letter-spacing: -0.02em;
    line-height: 1.2;
}

.section-desc {
    font-size: 1.1rem;
    color: var(--gray);
    max-width: 700px;
    margin-bottom: 48px;
}

/* --- Filosofía --- */
.section-filosofia {
    background: var(--white);
}

.filosofia-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    margin-top: 48px;
}

.filosofia-text .lead {
    font-size: 1.2rem;
    color: var(--dark);
    margin-bottom: 20px;
    line-height: 1.7;
}

.filosofia-text p {
    color: var(--gray);
    margin-bottom: 16px;
    line-height: 1.7;
}

.filosofia-visual {
    display: flex;
    justify-content: center;
}

.visual-card {
    display: flex;
    align-items: center;
    gap: 24px;
    background: var(--light);
    padding: 40px;
    border-radius: var(--radius-lg);
}

.visual-icon {
    font-size: 3rem;
}

.visual-label {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--dark);
}

.visual-arrow {
    font-size: 2rem;
    color: var(--primary);
    font-weight: 700;
}

/* --- Qué Aprenderás --- */
.section-aprenderas {
    background: var(--light);
}

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

.topic-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: 32px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-top: 4px solid var(--accent);
}

.topic-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.topic-icon {
    font-size: 2.5rem;
    margin-bottom: 16px;
}

.topic-card h3 {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--dark);
    margin-bottom: 12px;
}

.topic-card p {
    color: var(--gray);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* --- Oferta Educativa --- */
.section-oferta {
    background: var(--white);
}

.oferta-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 32px;
    margin-top: 48px;
}

.oferta-card {
    background: var(--white);
    border: 2px solid var(--light);
    border-radius: var(--radius-lg);
    padding: 40px;
    position: relative;
    transition: var(--transition);
}

.oferta-card:hover {
    border-color: var(--primary-light);
    box-shadow: var(--shadow-lg);
}

.oferta-card.featured {
    border-color: var(--primary);
    background: linear-gradient(180deg, rgba(37, 99, 235, 0.02) 0%, var(--white) 100%);
}

.oferta-badge {
    position: absolute;
    top: -12px;
    right: 24px;
    background: var(--gradient);
    color: var(--white);
    padding: 6px 16px;
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 700;
}

.oferta-header {
    margin-bottom: 20px;
}

.oferta-icon {
    font-size: 2.5rem;
    margin-bottom: 12px;
}

.oferta-header h3 {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--dark);
}

.oferta-desc {
    color: var(--gray);
    margin-bottom: 24px;
    line-height: 1.6;
}

.oferta-features {
    margin-bottom: 32px;
}

.oferta-features li {
    padding: 10px 0;
    border-bottom: 1px solid var(--light);
    color: var(--dark-soft);
    font-size: 0.95rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

.oferta-features li::before {
    content: "✓";
    color: var(--success);
    font-weight: 700;
}

/* --- Por Qué Elegirnos --- */
.section-porque {
    background: var(--light);
}

.porque-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 32px;
    margin-top: 48px;
}

.porque-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: 40px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.porque-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.porque-number {
    font-size: 3rem;
    font-weight: 800;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 16px;
    line-height: 1;
}

.porque-card h3 {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--dark);
    margin-bottom: 12px;
}

.porque-card p {
    color: var(--gray);
    line-height: 1.6;
}

/* --- CTA --- */
.section-cta {
    background: var(--gradient);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.section-cta::before {
    content: '';
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(circle at 20% 50%, rgba(255,255,255,0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(255,255,255,0.08) 0%, transparent 40%);
}

.cta-title {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800;
    color: var(--white);
    margin-bottom: 16px;
    position: relative;
}

.cta-desc {
    font-size: 1.15rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 40px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
    position: relative;
}

.cta-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    position: relative;
}

/* --- Footer --- */
.footer {
    background: var(--dark);
    color: var(--gray-light);
    padding: 60px 0 30px;
}

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

.footer-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--white);
    margin-bottom: 16px;
}

.footer-brand .logo-icon {
    width: 36px;
    height: 36px;
    font-size: 1.2rem;
}

.footer-text {
    max-width: 500px;
    margin: 0 auto 24px;
    font-size: 0.95rem;
    line-height: 1.6;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 32px;
    flex-wrap: wrap;
    margin-bottom: 32px;
    padding-bottom: 32px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-links a {
    font-size: 0.9rem;
    transition: var(--transition);
}

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

.footer-copy {
    font-size: 0.85rem;
    color: var(--gray);
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 24px;
        gap: 16px;
        border-bottom: 1px solid var(--light);
        box-shadow: var(--shadow-lg);
    }

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

    .menu-toggle {
        display: flex;
    }

    .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);
    }

    .filosofia-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .visual-card {
        flex-direction: column;
        text-align: center;
    }

    .section {
        padding: 60px 0;
    }

    .oferta-grid {
        grid-template-columns: 1fr;
    }

    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .hero-cta {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        justify-content: center;
    }

    .topics-grid {
        grid-template-columns: 1fr;
    }

    .porque-grid {
        grid-template-columns: 1fr;
    }

    .footer-links {
        flex-direction: column;
        gap: 16px;
    }
}

/* --- Animaciones --- */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-in {
    animation: fadeInUp 0.6s ease forwards;
}

/* --- Scroll animations --- */
.topic-card,
.oferta-card,
.porque-card {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.topic-card.visible,
.oferta-card.visible,
.porque-card.visible {
    opacity: 1;
    transform: translateY(0);
}