:root {
    --primary-color: #1a1a1a;    
    --accent-color: #d63031;     
    --text-color: #2d3436;       
    --bg-color: #ffffff;
    --light-gray: #f5f6fa;
    --border-radius: 12px;   
    --font-heading: 'Oswald', sans-serif;
    --font-body: 'Source Sans 3', sans-serif;
}

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

body {
    font-family: var(--font-body);
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    overflow-x: hidden; /* Evita scroll horizontal en móvil */
}
a:focus, button:focus {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

a { text-decoration: none; color: inherit; transition: 0.3s; }
ul { list-style: none; }

/* header */
.main-header {
    position: sticky; /* para que se quede quieto al bajar */
    top: 0;
    background-color: rgba(255, 255, 255, 0.95); /* Efecto vidrio */
    backdrop-filter: blur(10px); /* Efecto moderno */
    height: 70px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 5%;
    z-index: 1000;
    border-bottom: 1px solid #e1e1e1;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.logo-text {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.5rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--primary-color);
}

.punto { color: var(--accent-color); font-size: 2rem; line-height: 0; }

.main-nav ul {
    display: flex;
    gap: 30px;
}

.nav-link {
    font-weight: 600;
    font-size: 0.95rem;
    text-transform: uppercase;
    position: relative;
}

/* para subrayar las palabritas del nav */
.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: var(--accent-color);
    transition: width 0.3s;
}

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

.nav-link.highlight {
    color: var(--accent-color);
}

/* Botón móvil oculto en escritorio */
.menu-toggle { display: none; }

/* imagen principal iconica */
.hero {
    height: 85vh; /* Ocupa casi toda la pantalla */
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    /* Imagen de fondo con efecto Parallax */
    background-image: url('assets/di3.jpg'); 
    background-size: cover;
    background-position: center;
    background-attachment: fixed; /* Parallax effect */
}

/* Capa oscura para que se lea el texto (Accesibilidad) */
.hero-overlay {
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    background: linear-gradient(rgba(0,0,0,0.3), rgba(0,0,0,0.7));
}

.hero-content {
    position: relative;
    z-index: 2;
    color: white;
    max-width: 800px;
    padding: 20px;
}

.hero-content h1 {
    font-family: var(--font-heading);
    font-size: 4rem;
    line-height: 1.1;
    margin-bottom: 20px;
    text-shadow: 2px 2px 10px rgba(0,0,0,0.5);
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 30px;
    font-weight: 300;
}

.btn-primary {
    display: inline-block;
    padding: 12px 30px;
    background-color: var(--accent-color);
    color: white;
    font-weight: 600;
    border-radius: 50px; /* Botón píldora */
    text-transform: uppercase;
    letter-spacing: 1px;
    box-shadow: 0 4px 15px rgba(214, 48, 49, 0.4);
}

.btn-primary:hover {
    background-color: #b71c1c;
    transform: translateY(-3px); /* Pequeña animación hacia arriba */
}

/*Autorr*/
.about-section {
    padding: 80px 5%;
    background-color: white;
}

.about-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.about-image img {
    width: 100%;
    border-radius: var(--border-radius);
    box-shadow: 20px 20px 0px var(--light-gray); /* Efecto decorativo */
}

.label-small {
    color: var(--accent-color);
    font-weight: 700;
    text-transform: uppercase;
    font-size: 0.8rem;
    letter-spacing: 2px;
}

.about-text h2 {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    margin: 10px 0 20px 0;
    color: var(--primary-color);
}

.btn-text {
    display: inline-block;
    margin-top: 20px;
    font-weight: 700;
    color: var(--primary-color);
    border-bottom: 2px solid var(--accent-color);
}

/* articulos */
.content-section {
    padding: 80px 5%;
    background-color: var(--light-gray);
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h3 {
    font-family: var(--font-heading);
    font-size: 2.5rem;
}

.articles-grid {
    display: grid;
    /* Responsive automático */
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); 
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
}

/* Estilo de la Tarjeta */
.card {
    background: white;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
}

/* Hover effect: tarjeta */
.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.1);
}

.card-image {
    position: relative;
    height: 250px;
    overflow: hidden;
}

.card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

/* Zoom en la imagen*/
.card:hover .card-image img {
    transform: scale(1.1);
}

.card-tag {
    position: absolute;
    top: 15px;
    right: 15px;
    background-color: rgba(0,0,0,0.7);
    color: white;
    padding: 5px 12px;
    font-size: 0.8rem;
    border-radius: 20px;
    font-weight: 600;
}

.card-content {
    padding: 25px;
}

.card-content h4 {
    font-family: var(--font-heading);
    font-size: 1.4rem;
    margin-bottom: 10px;
}

.card-content p {
    font-size: 0.95rem;
    color: #636e72;
    margin-bottom: 20px;
}

.read-more {
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--primary-color);
}

/* banner y el footer */
.impact-banner {
    background-color: var(--primary-color);
    color: white;
    padding: 60px 20px;
    text-align: center;
     /* Imagen de fondo con efecto Parallax */
    background-image: url('assets/proyectos-africa.jpg'); 
    background-size: cover;
    background-position: center;
    background-attachment: fixed; /* Parallax effect */ 
    }

.impact-banner h3 {
    font-family: var(--font-heading);
    font-size: 2rem;
    margin-bottom: 10px;
       /* Imagen de fondo con efecto Parallax */
    background-image: url('assets/proyectos-africa.jpg'); 
    background-size: cover;
    background-position: center;
    background-attachment: fixed; /* Parallax effect */ 
}

footer {
    background-color: #111;
    color: #888;
    padding: 40px 5%;
    border-top: 1px solid #333;
}

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

.footer-links a {
    margin-left: 20px;
    font-size: 0.9rem;
}

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

/* Responsive para el movil. */
@media (max-width: 768px) {
    .main-nav { display: none; } 
    .menu-toggle { display: block; background: none; border: none; font-size: 2rem; cursor: pointer; }
    .menu-toggle span { display: block; width: 25px; height: 3px; background: #333; margin: 5px 0; }
    
    .hero-content h1 { font-size: 2.5rem; }
    
    .about-container { grid-template-columns: 1fr; }
    .about-image { order: -1; } 
    
    .footer-content { flex-direction: column; gap: 20px; text-align: center; }
    .footer-links a { margin: 0 10px; }
}