/* =============================================
   BATERÍAS POR UN TUBO - Estilos principales
   Colores: Primario #B80000, Fondo #FFFFFF
   ============================================= */

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

:root {
    --primary: #B80000;
    --primary-dark: #8B0000;
    --primary-light: #D43D3D;
    --bg: #FFFFFF;
    --bg-light: #F8F8F8;
    --bg-dark: #1A1A1A;
    --text: #222222;
    --text-light: #666666;
    --text-white: #FFFFFF;
    --border: #E0E0E0;
    --shadow: 0 2px 12px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
    --radius: 8px;
    --transition: all 0.3s ease;
    --max-width: 1200px;
    --header-height: 70px;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--header-height);
}

body {
    font-family: 'Roboto', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

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

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

ul { list-style: none; }

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* =============================================
   HEADER / NAVEGACIÓN
   ============================================= */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--bg);
    box-shadow: 0 1px 8px rgba(0,0,0,0.08);
    height: var(--header-height);
}

.header-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.logo-link {
    display: flex;
    align-items: center;
    flex-shrink: 0;
}

.logo-img {
    height: 50px;
    width: auto;
}

.main-nav {
    display: flex;
    align-items: center;
}

.nav-list {
    display: flex;
    align-items: center;
    gap: 4px;
}

.nav-link {
    display: block;
    padding: 8px 14px;
    font-size: 0.875rem;
    font-weight: 500;
    font-family: 'Open Sans', 'Segoe UI', sans-serif;
    color: var(--text);
    border-radius: var(--radius);
    position: relative;
    transition: var(--transition);
    white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary);
    background: rgba(184, 0, 0, 0.06);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 2px;
    left: 14px;
    right: 14px;
    height: 2px;
    background: var(--primary);
    border-radius: 2px;
}

/* Submenu */
.has-submenu {
    position: relative;
}

.has-submenu .arrow {
    font-size: 0.65rem;
    margin-left: 2px;
}

.submenu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background: var(--bg);
    box-shadow: var(--shadow-lg);
    border-radius: var(--radius);
    min-width: 180px;
    padding: 8px 0;
    z-index: 100;
}

.submenu li a {
    display: block;
    padding: 8px 16px;
    font-size: 0.85rem;
    color: var(--text);
}

.submenu li a:hover {
    background: rgba(184, 0, 0, 0.06);
    color: var(--primary);
}

.has-submenu:hover .submenu {
    display: block;
}

/* Botón contacto en nav */
.nav-link.btn-contact {
    background: var(--primary);
    color: var(--text-white);
    font-weight: 600;
}

.nav-link.btn-contact:hover {
    background: var(--primary-dark);
    color: var(--text-white);
}

/* Hamburger */
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.hamburger span {
    display: block;
    width: 26px;
    height: 3px;
    background: var(--text);
    border-radius: 2px;
    transition: var(--transition);
}

.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 6px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -6px); }

/* =============================================
   HERO SECTION
   ============================================= */
.hero {
    position: relative;
    height: 500px;
    min-height: 500px;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: var(--header-height);
}

.hero-video-overlay {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: linear-gradient(135deg, rgba(0,0,0,0.55) 0%, rgba(0,0,0,0.35) 50%, rgba(184,0,0,0.25) 100%);
    z-index: 2;
}

.hero-video {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    object-fit: cover;
    z-index: 1;
}

.hero-bg-fallback {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: linear-gradient(135deg, #1a1a1a 0%, #333 50%, #B80000 100%);
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 3;
    text-align: center;
    color: var(--text-white);
    padding: 0 20px;
    max-width: 800px;
}

.hero-slogan {
    font-size: 2.8rem;
    font-weight: 700;
    line-height: 1.15;
    margin-bottom: 16px;
    text-shadow: 0 2px 10px rgba(0,0,0,0.3);
}

.hero-subtitle {
    font-size: 1.15rem;
    margin-bottom: 32px;
    opacity: 0.9;
    font-weight: 300;
}

/* =============================================
   BOTONES
   ============================================= */
.btn {
    display: inline-block;
    padding: 14px 32px;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: var(--transition);
    text-align: center;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(184, 0, 0, 0.4);
}

.btn-outline {
    background: transparent;
    color: var(--text-white);
    border: 2px solid var(--text-white);
}

.btn-outline:hover {
    background: var(--text-white);
    color: var(--primary);
}

.btn-whatsapp {
    background: #25D366;
    color: var(--text-white);
}

.btn-whatsapp:hover {
    background: #1da851;
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(37, 211, 102, 0.4);
}

/* =============================================
   SECCIONES GENERALES
   ============================================= */
.section {
    padding: 80px 0;
}

.section-light {
    background: var(--bg-light);
}

.section-dark {
    background: var(--bg-dark);
    color: var(--text-white);
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--text);
    text-align: center;
}

.section-title.text-white { color: var(--text-white); }

.section-subtitle {
    text-align: center;
    color: var(--text-light);
    font-size: 1.05rem;
    max-width: 700px;
    margin: 0 auto 48px;
}

.section-subtitle.text-light { color: rgba(255,255,255,0.7); }

/* Texto + Imagen layout */
.text-image-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.text-image-grid .text h2 {
    font-size: 2rem;
    margin-bottom: 20px;
    color: var(--text);
}

.text-image-grid .text p {
    color: var(--text-light);
    margin-bottom: 16px;
    font-size: 1.02rem;
    line-height: 1.75;
}

.text-image-grid .image img {
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    width: 100%;
    height: auto;
}

/* =============================================
   PUNTOS FUERTES / BLOQUES DE PRODUCTO
   ============================================= */
.features-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 60px;
}

.feature-card {
    text-align: center;
    padding: 40px 24px;
    background: var(--bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border);
}

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

.feature-icon {
    font-size: 2.8rem;
    margin-bottom: 18px;
    display: block;
}

.feature-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--primary);
}

.feature-card p {
    color: var(--text-light);
    font-size: 0.92rem;
    line-height: 1.6;
}

/* Cards con imagen (tyre-type-card, lubricant-card) */
.tyre-types-grid,
.lubricant-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 48px;
}

.tyre-type-card,
.lubricant-card {
    text-align: center;
    padding: 40px 24px;
    background: var(--bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border);
}

.tyre-type-card:hover,
.lubricant-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}

.tyre-type-card .card-body,
.lubricant-card .lub-icon {
    padding: 0;
}

.lubricant-card .lub-icon {
    font-size: 2.8rem;
    margin-bottom: 18px;
    display: block;
}

.tyre-type-card h3,
.lubricant-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--primary);
}

.tyre-type-card p,
.lubricant-card p {
    color: var(--text-light);
    font-size: 0.92rem;
    line-height: 1.6;
}

/* =============================================
   SLIDER MARCAS
   ============================================= */
.brands-section {
    padding: 60px 0;
    background: var(--bg);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.brands-section h2 {
    text-align: center;
    margin-bottom: 40px;
    font-size: 1.5rem;
    color: var(--text);
}

.brands-slider {
    overflow: hidden;
    position: relative;
}

.brands-track {
    display: flex;
    align-items: center;
    gap: 60px;
    animation: scrollBrands 30s linear infinite;
    width: max-content;
}

.brand-item {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 80px;
    min-width: 160px;
    padding: 10px 20px;
}

.brand-item img {
    max-height: 60px;
    max-width: 140px;
    object-fit: contain;
    transition: var(--transition);
    filter: grayscale(100%);
    opacity: 0.7;
}

.brand-item:hover img {
    filter: grayscale(0%);
    opacity: 1;
}

.brand-item span {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-light);
    letter-spacing: 0.5px;
    transition: var(--transition);
}

.brand-item:hover span {
    color: var(--primary);
}

@keyframes scrollBrands {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}

/* =============================================
   TABS BATERÍAS ARRANQUE
   ============================================= */
.tabs-wrapper { max-width: 900px; margin: 0 auto; }

.tab-buttons {
    display: flex;
    gap: 12px;
    margin-bottom: 36px;
    flex-wrap: wrap;
}

.tab-btn {
    padding: 12px 28px;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    background: var(--bg);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text);
}

.tab-btn:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.tab-btn.active {
    border-color: var(--primary);
    background: var(--primary);
    color: var(--text-white);
}

.tab-content {
    display: none;
    animation: fadeIn 0.4s ease;
}

.tab-content.active { display: block; }

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

.tab-content h3 {
    font-size: 1.5rem;
    color: var(--primary);
    margin-bottom: 16px;
}

.tab-content p {
    color: var(--text-light);
    line-height: 1.8;
    font-size: 1.02rem;
}

/* =============================================
   INDUSTRIAL / TRACCIÓN LANDING
   ============================================= */
.landing-hero {
    background: linear-gradient(135deg, #1a1a1a 0%, #2c2c2c 50%, #B80000 100%);
    color: var(--text-white);
    padding: 120px 0 80px;
    text-align: center;
}

.landing-hero h1 {
    font-size: 2.4rem;
    margin-bottom: 20px;
}

.landing-hero p {
    font-size: 1.05rem;
    opacity: 0.85;
    max-width: 700px;
    margin: 0 auto 24px;
    line-height: 1.7;
}

/* =============================================
   FORMULARIO
   ============================================= */
.contact-form-wrapper {
    max-width: 600px;
    margin: 0 auto;
}

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

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 6px;
    font-size: 0.92rem;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-size: 1rem;
    font-family: inherit;
    background: var(--bg);
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(184, 0, 0, 0.1);
}

.form-group textarea {
    min-height: 130px;
    resize: vertical;
}

.form-inline {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    justify-content: center;
    margin: 32px 0;
}

/* =============================================
   LUBRICANTES
   ============================================= */

/* =============================================
   CONTACTO
   ============================================= */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}

.contact-info h2 {
    font-size: 1.8rem;
    margin-bottom: 16px;
}

.contact-info p {
    color: var(--text-light);
    margin-bottom: 24px;
    line-height: 1.7;
}

.contact-methods {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.contact-method {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.02rem;
}

.contact-method .icon {
    font-size: 1.4rem;
}

.whatsapp-big-btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background: #25D366;
    color: var(--text-white);
    padding: 16px 32px;
    border-radius: var(--radius);
    font-size: 1.15rem;
    font-weight: 700;
    margin-top: 24px;
    transition: var(--transition);
}

.whatsapp-big-btn:hover {
    background: #1da851;
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(37, 211, 102, 0.4);
}

/* =============================================
   FOOTER
   ============================================= */
.footer {
    background: var(--bg-dark);
    color: var(--text-white);
    padding: 60px 0 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-col h4 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-white);
}

.footer-col p,
.footer-col a {
    color: rgba(255,255,255,0.6);
    font-size: 0.9rem;
    line-height: 1.7;
}

.footer-col a:hover {
    color: var(--primary-light);
}

.footer-col ul li {
    margin-bottom: 8px;
}

.footer-bottom {
    padding: 20px 0;
    text-align: center;
    color: rgba(255,255,255,0.4);
    font-size: 0.85rem;
}

.footer-bottom a {
    color: rgba(255,255,255,0.5);
}

.footer-bottom a:hover {
    color: var(--primary-light);
}

/* =============================================
   RESPONSIVE
   ============================================= */
@media (max-width: 992px) {
    .text-image-grid,
    .contact-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .features-row,
    .tyre-types-grid,
    .lubricant-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

    .hero-slogan {
        font-size: 2.2rem;
    }
}

@media (max-width: 768px) {
    :root { --header-height: 60px; }

    .logo-img { height: 40px; }

    .hero { height: 400px; min-height: 400px; }
    .hero-slogan { font-size: 1.6rem; }

    .hamburger { display: flex; }

    .main-nav {
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        bottom: 0;
        background: var(--bg);
        z-index: 999;
        display: none;
        overflow-y: auto;
        padding: 20px;
    }

    .main-nav.open { display: block; }

    .nav-list {
        flex-direction: column;
        align-items: stretch;
        gap: 4px;
    }

    .nav-link {
        padding: 14px 16px;
        font-size: 1rem;
        border-bottom: 1px solid var(--border);
    }

    .submenu {
        position: static;
        box-shadow: none;
        padding-left: 16px;
        display: none;
    }

    .has-submenu.open .submenu {
        display: block;
    }

    .hero-slogan {
        font-size: 1.8rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .section { padding: 60px 0; }

    .section-title { font-size: 1.6rem; }

    .features-row,
    .tyre-types-grid,
    .lubricant-grid {
        grid-template-columns: 1fr;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .tab-buttons {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .hero { height: 350px; min-height: 350px; }
    .hero-slogan { font-size: 1.4rem; }

    .btn { padding: 12px 24px; font-size: 0.92rem; }

    .landing-hero h1 { font-size: 1.6rem; }
}