/* =============================================
   1. VARIABLES Y RESET GLOBAL
   ============================================= */
:root {
    --primary: #1f3c88;
    --primary-dark: #14285a; /* Azul Oxford Premium */
    --accent: #e63946;
    --carton: #d2a679;
    --carton-dark: #b08d6a;
    --bg: #f4f7ff;
    --white: #ffffff;
    --shadow: rgba(0, 0, 0, 0.1);
    --transition: 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
}

* { 
    margin: 0; 
    padding: 0; 
    box-sizing: border-box; 
    font-family: 'Poppins', sans-serif; 
}

html { 
    scroll-behavior: smooth; 
}

body { 
    background: var(--bg); 
    color: #333; 
    overflow-x: hidden; 
}

/* =============================================
   2. PRELOADER (CAMIÓN ANIMADO)
   ============================================= */
#preloader { 
    position: fixed; 
    top: 0; 
    left: 0; 
    width: 100%; 
    height: 100vh; 
    background: var(--white); 
    z-index: 5000; 
    display: flex; 
    flex-direction: column; 
    justify-content: center; 
    align-items: center; 
    transition: 0.6s ease-in-out; 
}

.road-container { 
    width: 300px; 
    height: 100px; 
    position: relative; 
    display: flex; 
    align-items: flex-end; 
    overflow: hidden; 
}

.loader-truck { 
    width: 85px; 
    height: 45px; 
    position: absolute; 
    left: -100px; 
    bottom: 10px; 
    animation: drive 2.5s infinite linear; 
    display: flex; 
    align-items: flex-end; 
}

.truck-body { 
    width: 55px; 
    height: 35px; 
    background: var(--primary); 
    border-radius: 4px; 
    position: relative; 
}

.truck-stripe { 
    position: absolute; 
    top: 10px; 
    width: 100%; 
    height: 5px; 
    background: var(--accent); 
}

.truck-cabin-front { 
    width: 22px; 
    height: 25px; 
    background: #eee; 
    border: 3px solid var(--primary); 
    border-radius: 0 10px 0 0; 
    margin-left: -2px; 
}

.truck-wheels-anim span { 
    position: absolute; 
    bottom: -6px; 
    width: 12px; 
    height: 12px; 
    background: #333; 
    border-radius: 50%; 
    animation: spin 0.4s infinite linear; 
}

.wheel-a { left: 8px; } 
.wheel-b { right: 35px; }

.road-line-moving { 
    width: 100%; 
    height: 3px; 
    background: #ddd; 
    position: absolute; 
    bottom: 0; 
}

@keyframes drive { to { left: 350px; } }
@keyframes spin { to { transform: rotate(360deg); } }

/* =============================================
   3. PARALLAX NUBES (FONDO)
   ============================================= */
.parallax-bg { 
    position: fixed; 
    top: 0; 
    left: 0; 
    width: 100%; 
    height: 100%; 
    z-index: -1; 
    pointer-events: none; 
}

.cloud { 
    position: absolute; 
    background: rgba(255,255,255,0.85); 
    border-radius: 50px; 
    filter: blur(1px);
}

.c1 { width: 150px; height: 40px; top: 15%; left: 10%; box-shadow: 180px 120px 0 -5px rgba(255,255,255,0.7); }
.c2 { width: 100px; height: 30px; top: 40%; right: 15%; }
.c3 { width: 220px; height: 50px; bottom: 20%; left: 20%; opacity: 0.4; }
.c4 { width: 180px; height: 45px; opacity: 0.6; } /* Nube extra */

/* =============================================
   4. HEADER Y NAVEGACIÓN
   ============================================= */
/* HEADER */
.header {
    padding: 15px 8%; background: rgba(255, 255, 255, 0.98); backdrop-filter: blur(10px);
    display: flex; justify-content: space-between; align-items: center;
    position: sticky; top: 0; z-index: 1000; box-shadow: 0 4px 20px rgba(0,0,0,0.05);
}
.logo { display: flex; align-items: center; gap: 12px; text-decoration: none; }
.logo img { height: 48px; transition: transform 0.3s; }
.logo:hover img { transform: rotate(-5deg) scale(1.1); }
.logo span { font-weight: 800; font-size: 24px; color: var(--primary); }

.nav { display: flex; gap: 30px; align-items: center; }
.nav a { text-decoration: none; color: var(--text-dark); font-weight: 600; font-size: 14px; transition: 0.3s; }
.nav a:hover:not(.btn-nav) { color: var(--accent); }
.btn-nav { background: var(--accent); color: white !important; padding: 12px 28px; border-radius: 50px; box-shadow: 0 8px 20px rgba(230, 57, 70, 0.2); }

.menu-toggle { 
    display: none; 
    font-size: 1.8rem; 
    color: var(--primary); 
    cursor: pointer; 
}

/* =============================================
   5. HERO SECTION (CORREGIDA CON BOTÓN)
   ============================================= */
.hero { 
    min-height: 100vh; 
    display: flex; 
    align-items: center; 
    padding: 120px 8% 60px; 
    background: #ffffff; 
    gap: 60px; 
    overflow: hidden;
}

.hero-content { 
    flex: 1; 
    z-index: 2;
}

.hero-content h1 { 
    font-size: 4.5rem; 
    color: #1a3a8a; /* Azul Oxford */
    line-height: 1.1; 
    margin-bottom: 25px; 
    font-weight: 800; 
}

.highlight { color: #e63946; } /* Color de acento si lo usas */

.hero-content p { 
    font-size: 1.3rem; 
    color: #4a5568; 
    margin-bottom: 45px; 
    line-height: 1.7;
    max-width: 550px;
}

/* ESTILO DEL BOTÓN PRINCIPAL */
.btn-main { 
    display: inline-block; 
    padding: 20px 45px; 
    background: #1e3a8a; /* Azul oscuro de tu captura */
    color: #ffffff !important; 
    text-decoration: none; 
    border-radius: 50px; /* Bordes muy redondeados */
    font-weight: 700; 
    font-size: 1.1rem; 
    transition: all 0.4s ease; 
    box-shadow: 0 15px 30px rgba(30, 58, 138, 0.25); /* Sombra suave */
    border: none;
    cursor: pointer;
}

.btn-main:hover { 
    transform: translateY(-5px); 
    box-shadow: 0 20px 40px rgba(30, 58, 138, 0.35);
    background: #e63946; /* Un poco más oscuro al pasar el ratón */
}

/* ILUSTRACIÓN GRANDE */
.hero-illustration { 
    flex: 1.2; 
    display: flex;
    justify-content: center;
}

.hero-illustration img { 
    width: 115%; 
    max-width: 800px;
    height: auto;
    filter: drop-shadow(0 20px 40px rgba(0,0,0,0.05));
    animation: float 6s infinite ease-in-out; 
}

/* RESPONSIVE */
@media (max-width: 1024px) {
    .hero {
        flex-direction: column; 
        text-align: center;
        padding-top: 140px;
    }
    .hero-content {
        order: 2;
        display: flex;
        flex-direction: column;
        align-items: center;
    }
    .hero-illustration {
        order: 1;
        width: 100%;
        margin-bottom: 40px;
    }
    .hero-illustration img {
        width: 90%;
        max-width: 450px;
    }
    .hero-content h1 { font-size: 3rem; }
}

@keyframes float { 
    0%, 100% { transform: translateY(0); } 
    50% { transform: translateY(-25px); } 
}

/* =============================================
   6. SERVICIOS (4 CAJAS 3D)
   ============================================= */
.services { 
    padding: 120px 8%; 
    text-align: center; 
}

.section-title { 
    font-size: 3.2rem; 
    color: var(--primary); 
    font-weight: 800; 
    margin-bottom: 120px; 
    position: relative; 
}

.services-grid { 
    display: flex; 
    justify-content: center; 
    gap: 50px; 
    flex-wrap: wrap; 
}

.scene { 
    width: 220px; 
    height: 220px; 
    perspective: 1200px; 
    margin-bottom: 40px; 
}

.box-3d { 
    width: 100%; 
    height: 100%; 
    position: relative; 
    transform-style: preserve-3d; 
    transform: rotateX(-20deg) rotateY(25deg); 
    transition: 0.7s cubic-bezier(0.175, 0.885, 0.32, 1.275); 
    cursor: pointer; 
}

.face { 
    position: absolute; 
    width: 220px; 
    height: 220px; 
    background: var(--carton); 
    border: 1px solid rgba(0,0,0,0.1); 
    box-shadow: inset 0 0 30px rgba(0,0,0,0.05); 
}

.front { transform: translateZ(110px); }
.back { transform: rotateY(180deg) translateZ(110px); background: var(--carton-dark); }
.left { transform: rotateY(-90deg) translateZ(110px); background: var(--carton-dark); }
.right { transform: rotateY(90deg) translateZ(110px); background: var(--carton-dark); }
.bottom { transform: rotateX(-90deg) translateZ(110px); background: #8e6e4e; }

.lid-l, .lid-r { 
    position: absolute; 
    top: 0; 
    width: 110px; 
    height: 220px; 
    background: var(--carton); 
    transform: rotateX(90deg) translateZ(110px); 
    transition: 0.6s; 
    z-index: 5; 
}

.lid-l { left: 0; transform-origin: left; }
.lid-r { right: 0; transform-origin: right; }

.tape { 
    position: absolute; 
    top: -110px; 
    left: 95px; 
    width: 30px; 
    height: 220px; 
    background: rgba(160, 130, 80, 0.4); 
    transform: rotateX(90deg) translateZ(1px); 
}

.sticker { 
    position: absolute; 
    top: 25px; 
    left: 15px; 
    color: var(--white); 
    padding: 4px 10px; 
    font-size: 11px; 
    font-weight: 800; 
    transform: rotate(-12deg); 
    border-radius: 3px; 
}

.sticker.red { background: var(--accent); }
.sticker.blue { background: var(--primary); }

.tap-hint { 
    position: absolute; 
    bottom: 20px; 
    left: 50%; 
    transform: translateX(-50%); 
    background: rgba(0,0,0,0.6); 
    color: var(--white); 
    padding: 5px 12px; 
    border-radius: 20px; 
    font-size: 10px; 
    font-weight: 700; 
}

.card-inner { 
    position: absolute; 
    top: 20px; 
    left: 20px; 
    width: 180px; 
    background: var(--white); 
    padding: 25px; 
    border-radius: 15px; 
    opacity: 0; 
    transition: 0.6s; 
    box-shadow: 0 15px 40px rgba(0,0,0,0.2); 
    text-align: center; 
}

.card-inner i { font-size: 38px; color: var(--accent); margin-bottom: 15px; }

/* Asegúrate de que la caja tenga estas transiciones */
.box-3d { 
    transform-style: preserve-3d; 
    transform: rotateX(-20deg) rotateY(25deg); 
    transition: 0.7s cubic-bezier(0.175, 0.885, 0.32, 1.275); 
}

/* TUS COORDENADAS: Cuando tiene la clase .open */
.box-3d.open { 
    transform: rotateX(-5deg) rotateY(0deg); 
}

.box-3d.open .lid-l { 
    transform: rotateX(90deg) translateZ(110px) rotateY(-135deg); 
}

.box-3d.open .lid-r { 
    transform: rotateX(90deg) translateZ(110px) rotateY(135deg); 
}

.box-3d.open .card-inner { 
    opacity: 1; 
    transform: translateZ(160px) translateY(-260px) scale(1.1); 
    transition: 0.6s delay 0.1s; /* Un pequeño delay para que la tapa abra primero */
}
/* =============================================
   7. PROCESO (DISEÑO PREMIUM OXFORD ACTUALIZADO)
   ============================================= */
.process-section { 
    padding: 120px 8%; 
    text-align: center; 
    background: var(--white); 
}

.trucks-container { 
    display: flex; 
    justify-content: center; 
    gap: 30px; 
    flex-wrap: wrap; 
}

.truck-rear { 
    width: 260px; 
    cursor: pointer; 
    transition: var(--transition);
}

/* El chasis del camión con profundidad */
.truck-box-back { 
    height: 200px; 
    background: #0a1931; 
    border-radius: 12px 12px 0 0; 
    position: relative; 
    overflow: hidden; 
    border: 6px solid #1a1a1a; 
    box-shadow: inset 0 0 40px rgba(0,0,0,0.8);
}

/* La persiana metálica */
.truck-shutter { 
    position: absolute; 
    top: 0; 
    left: 0; 
    width: 100%; 
    height: 100%; 
    background: repeating-linear-gradient(
        #eee 0px, 
        #eee 10px, 
        #d1d1d1 10px, 
        #d1d1d1 12px
    ); 
    z-index: 10; 
    transition: 0.8s cubic-bezier(0.77, 0, 0.175, 1); 
    display: flex; 
    flex-direction: column;
    align-items: center; 
    justify-content: flex-end; 
    padding-bottom: 20px;
}

.shutter-handle { 
    width: 50px; 
    height: 6px; 
    background: #333; 
    border-radius: 10px; 
    box-shadow: inset 0 2px 2px rgba(0,0,0,0.3);
}

.tap-hint-truck {
    font-size: 10px;
    font-weight: 700;
    color: #666;
    margin-top: 8px;
    letter-spacing: 1px;
}

/* Apertura */
.truck-rear:hover .truck-shutter, 
.truck-rear.active-mob .truck-shutter { 
    transform: translateY(-94%); 
}

/* Interior: Estilo Oxford Premium */
.truck-interior { 
    width: 100%; 
    height: 100%; 
    display: flex; 
    flex-direction: column; 
    justify-content: center; 
    align-items: center; 
    padding: 15px;
    background: radial-gradient(circle at center, #1f3c88 0%, #0a1931 100%); 
    text-align: center;
}

/* Distintivo de paso en Dorado */
.step-badge {
    font-size: 0.7rem;
    font-weight: 800;
    color: #ffd700; 
    text-transform: uppercase;
    letter-spacing: 2px;
    border: 1px solid rgba(255, 215, 0, 0.4);
    padding: 2px 10px;
    border-radius: 20px;
    margin-bottom: 12px;
    background: rgba(255, 215, 0, 0.05);
}

.truck-interior i {
    font-size: 2.2rem;
    color: var(--white);
    margin-bottom: 10px;
    filter: drop-shadow(0 0 10px rgba(255,255,255,0.3));
}

.truck-interior h4 {
    color: var(--white);
    font-size: 1.1rem;
    font-weight: 700;
    text-transform: uppercase;
    margin-bottom: 5px;
}

.truck-interior p {
    color: #cbd5e0;
    font-size: 0.75rem;
    line-height: 1.4;
    max-width: 85%;
}

/* Paragolpes y Luces Dinámicas */
.truck-lights { 
    height: 50px; 
    background: #1a1a1a; 
    display: flex; 
    justify-content: space-between; 
    align-items: center; 
    padding: 0 15px; 
    border-radius: 0 0 12px 12px; 
    border-top: 2px solid #333;
}

.light-l, .light-r { 
    width: 35px; 
    height: 14px; 
    background: #440000; 
    border-radius: 3px; 
    transition: 0.3s;
}

.truck-rear:hover .light-l, .truck-rear:hover .light-r,
.truck-rear.active-mob .light-l, .truck-rear.active-mob .light-r {
    background: #ff0000;
    box-shadow: 0 0 15px #ff0000, 0 0 30px rgba(255,0,0,0.5);
}

.plate { 
    color: #f1c40f; 
    font-family: 'Courier New', monospace;
    font-size: 12px; 
    font-weight: 900; 
    border: 1px solid #444; 
    padding: 2px 8px; 
    background: #000; 
    border-radius: 2px;
}

/* =============================================
   8. CALCULADORA (DISEÑO PREMIUM FINAL)
   ============================================= */
.calculator-section { 
    padding: 120px 8%; 
    background: #f4f7fa; 
}

.calc-container { 
    max-width: 900px; 
    margin: 0 auto; 
    background: var(--white); 
    border-radius: 40px; 
    padding: 60px; 
    box-shadow: 0 40px 80px rgba(0,0,0,0.06);
    /* Asegura que el contenedor se adapte al contenido de forma fluida */
    min-height: 500px;
    display: flex;
    flex-direction: column;
}

.calc-header { 
    text-align: center; 
    margin-bottom: 60px; 
}

.calc-header h2 { 
    font-size: 3rem; 
    color: var(--primary); 
    font-weight: 800; 
    margin-bottom: 15px;
}

.calc-header p {
    color: #666;
    font-size: 1.1rem;
}

/* Pregunta actual con margen de seguridad */
.calc-step-title {
    display: block;
    text-align: center;
    font-size: 1.3rem;
    font-weight: 700;
    color: #333;
    margin-bottom: 40px;
}

/* Sistema de Pasos: Control de visibilidad */
.calc-step { 
    display: none; /* JS controlará el display: flex */
    flex-direction: column;
    opacity: 0;
    transform: translateY(20px);
    /* Transición suave para la entrada */
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.calc-step.active { 
    display: flex; 
    opacity: 1;
    transform: translateY(0);
}

/* Grid de Opciones */
.calc-options { 
    display: grid; 
    grid-template-columns: 1fr 1fr; 
    gap: 25px; 
}

.opt { 
    padding: 35px 25px; 
    border: 2px solid #f0f0f0; 
    border-radius: 25px; 
    text-align: center; 
    cursor: pointer; 
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275); 
    display: flex;
    flex-direction: column;
    align-items: center;
    background: #fff;
}

/* Iconos circulares Oxford */
.opt i { 
    width: 65px;
    height: 65px;
    background: #f8faff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem; 
    margin-bottom: 18px; 
    color: var(--primary); 
    transition: 0.3s;
}

.opt span {
    font-size: 1.1rem;
    font-weight: 700;
    color: #2d3748;
}

/* Efectos Hover */
.opt:hover { 
    border-color: var(--accent); 
    transform: translateY(-10px); 
    box-shadow: 0 15px 30px rgba(0,0,0,0.05);
}

.opt:hover i {
    background: var(--accent);
    color: white;
}

/* Resultado Final y Precio */
.price-tag { 
    font-size: 5.5rem; 
    font-weight: 900; 
    color: var(--primary); 
    text-align: center; 
    margin: 30px 0; 
    letter-spacing: -3px;
}

.price-tag span { font-size: 2.2rem; vertical-align: middle; margin-right: 8px; }

#calcSummary {
    text-align: center;
    font-size: 1.1rem;
    line-height: 1.6;
    max-width: 80%;
    margin: 0 auto 40px;
}

/* Botones de Acción Final */
.btn-whatsapp-send {
    background: #25d366;
    color: white;
    border: none;
    padding: 22px 35px;
    border-radius: 18px;
    font-weight: 800;
    font-size: 1.2rem;
    cursor: pointer;
    transition: 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    box-shadow: 0 10px 20px rgba(37, 211, 102, 0.2);
}

.btn-whatsapp-send:hover {
    background: #1eb954;
    transform: scale(1.02);
}

/* Botón Repetir */
.btn-reset {
    background: none;
    border: 2px solid #edf2f7;
    color: #718096;
    padding: 12px 25px;
    border-radius: 12px;
    margin: 25px auto 0;
    cursor: pointer;
    font-weight: 600;
    transition: 0.3s;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    width: max-content;
}

.btn-reset:hover {
    background: #f7fafc;
    border-color: #cbd5e0;
    color: var(--primary);
}

.btn-reset i { font-size: 0.9rem; }

/* Adaptabilidad Móvil */
@media (max-width: 768px) {
    .calc-options { grid-template-columns: 1fr; }
    .calc-container { padding: 40px 20px; }
    .price-tag { font-size: 4rem; }
}


.btn-whatsapp-send { 
    background: #25d366; 
    color: white; 
    border: none; 
    padding: 22px; 
    border-radius: 20px; 
    font-weight: 800; 
    width: 100%; 
    cursor: pointer; 
    font-size: 1.2rem; 
    transition: 0.3s;
    box-shadow: 0 10px 20px rgba(37, 211, 102, 0.2);
}

.btn-whatsapp-send:hover {
    background: #1eb954;
    transform: scale(1.02);
}

/* =============================================
   9. CONTACTO (PREMIUM OXFORD STYLE)
   ============================================= */
.contact-section {
    padding: 100px 8%;
    background: #fff;
}

.contact-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

/* Info lateral */
.contact-badge {
    color: var(--accent);
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 2px;
    font-size: 0.9rem;
    display: block;
    margin-bottom: 15px;
}

.contact-info h2 {
    font-size: 2.8rem;
    color: var(--primary);
    margin-bottom: 25px;
    line-height: 1.2;
}

.contact-info p {
    color: #666;
    font-size: 1.1rem;
    margin-bottom: 40px;
}

.info-items {
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 20px;
}

.info-icon {
    width: 50px;
    height: 50px;
    background: #f0f4f8;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    font-size: 1.2rem;
}

.info-item span {
    display: block;
    font-size: 0.8rem;
    color: #999;
    text-transform: uppercase;
    font-weight: 700;
}

.info-item p {
    margin: 0;
    font-weight: 700;
    color: var(--primary);
    font-size: 1.1rem;
}

/* Estilo del Formulario */
.contact-form-wrapper {
    background: #fff;
    padding: 50px;
    border-radius: 30px;
    box-shadow: 0 30px 60px rgba(0,0,0,0.08);
    border: 1px solid #f0f0f0;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 700;
    color: #333;
    font-size: 0.9rem;
}

.form-group input, .form-group textarea {
    width: 100%;
    padding: 15px;
    border: 2px solid #edf2f7;
    border-radius: 12px;
    font-family: inherit;
    transition: 0.3s;
}

.form-group input:focus, .form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    background: #f8faff;
}

.btn-submit {
    width: 100%;
    background: var(--primary);
    color: white;
    border: none;
    padding: 20px;
    border-radius: 12px;
    font-weight: 800;
    font-size: 1.1rem;
    cursor: pointer;
    transition: 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.btn-submit:hover {
    background: var(--accent);
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

/* Redes sociales */
.social-links {
    display: flex;
    gap: 15px;
    margin-top: 40px;
}

.social-links a {
    width: 45px;
    height: 45px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: 0.3s;
}

.social-links a:hover {
    background: var(--accent);
    transform: scale(1.1);
}

/* Responsivo */
@media (max-width: 992px) {
    .contact-container {
        grid-template-columns: 1fr;
        gap: 50px;
    }
    .contact-info h2 { font-size: 2.2rem; }
}

/* =============================================
   10. WHATSAPP Y REVEAL
   ============================================= */
.wa-container { 
    position: fixed; 
    bottom: 35px; 
    right: 35px; 
    z-index: 2000; 
    opacity: 0; 
    transform: scale(0.5); 
    transition: 0.5s; 
    pointer-events: none;
}

.wa-container.show { opacity: 1; transform: scale(1); pointer-events: all; }

.wa-btn { 
    width: 70px; 
    height: 70px; 
    background: #25d366; 
    color: white; 
    border-radius: 50%; 
    display: flex; 
    align-items: center; 
    justify-content: center; 
    font-size: 35px; 
    box-shadow: 0 10px 30px rgba(37,211,102,0.4); 
    text-decoration: none;
}

.reveal { 
    opacity: 0; 
    transform: translateY(50px); 
    transition: 1s cubic-bezier(0.165, 0.84, 0.44, 1); 
}

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

/* =============================================
   11. RESPONSIVE (MÓVIL) - NO QUITAR NADA
   ============================================= */
@media (max-width: 1024px) {
    .menu-toggle { display: block; }
    .nav {
        position: fixed;
        right: -100%;
        top: 0;
        height: 100vh;
        width: 75%;
        background: white;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        transition: 0.5s ease;
        box-shadow: -10px 0 30px rgba(0,0,0,0.1);
    }
    .nav.open { right: 0; }
    .nav a { margin: 20px 0; font-size: 1.3rem; margin-left: 0; }
    
    .hero { flex-direction: column; text-align: center; padding-top: 120px; }
    .hero-content h1 { font-size: 2.8rem; }
    .hero-illustration { text-align: center; }
}

@media (max-width: 768px) {
    .contact-grid { flex-direction: column; }
    .contact-info-panel, .contact-form-panel { padding: 40px 25px; }
    .section-title { font-size: 2.4rem; }
    .calc-options { grid-template-columns: 1fr 1fr; } /* Mantiene el 2x2 si caben */
}

@media (max-width: 480px) {
    .calc-options { grid-template-columns: 1fr; } /* En móviles muy pequeños 1 columna */
    .scene { width: 180px; height: 180px; }
    .face { width: 180px; height: 180px; }
    .front { transform: translateZ(90px); }
    /* Ajustes proporcionales para cajas pequeñas */
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* =============================================
   12. FOOTER (ESTILO OXFORD)
   ============================================= */
.main-footer {
    background: #1a3a8a; /* Azul muy oscuro, casi negro */
    color: #ffffff;
    padding: 80px 8% 40px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 40px;
    margin-bottom: 60px;
}

.footer-brand h2 {
    font-size: 1.8rem;
    font-weight: 800;
    margin-bottom: 15px;
}

.footer-brand p {
    color: #94a3b8;
    max-width: 300px;
}

.footer-links h4 {
    font-size: 1.1rem;
    margin-bottom: 20px;
    color: #f8fafc;
}

.footer-links p {
    color: #94a3b8;
    margin-bottom: 10px;
    font-size: 0.95rem;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 30px;
    text-align: center;
}

.footer-bottom p {
    color: #64748b;
    font-size: 0.85rem;
}

@media (max-width: 768px) {
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
    .footer-brand p {
        margin: 0 auto;
    }
}