/* ========================================
   V-FREE.COM - CSS OPTIMIZADO
   Código limpio, responsive, Core Web Vitals
   ======================================== */

/* ========================================
   1. VARIABLES CSS
   ======================================== */
:root {
    /* Colores */
    --color-primary: #DC0000;
    --color-black: #000000;
    --color-white: #FFFFFF;
    --color-gray: #666666;
    --color-gray-light: #F5F5F5;

    /* Tipografía */
    --font-family: Arial, Helvetica, sans-serif;
    --font-size-base: 16px;
    --font-size-h1: clamp(2.5rem, 5vw, 4rem);
    --font-size-h2: clamp(1.5rem, 3vw, 2rem);
    --font-size-body: clamp(0.875rem, 1.5vw, 1rem);
    --font-size-small: clamp(0.75rem, 1.2vw, 0.875rem);

    /* Espaciado */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;

    /* Layout */
    --max-content-width: 1400px;
    --border-width: 2px;
    --nav-height: 80px;

    /* Transiciones */
    --transition-fast: 0.2s ease;
    --transition-medium: 0.3s ease;

    /* Sombras */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.15);
}

/* ========================================
   2. RESET Y NORMALIZACIÓN
   ======================================== */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: var(--font-size-base);
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-body);
    line-height: 1.6;
    color: var(--color-black);
    background-color: var(--color-white);
    overflow-x: hidden;
}

body.menu-open {
    overflow: hidden;
}

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

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

ul {
    list-style: none;
}

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

/* ========================================
   3. NAVEGACIÓN STICKY
   ======================================== */
.nav {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--color-white);
    border-bottom: var(--border-width) solid var(--color-black);
    transition: box-shadow var(--transition-fast);
}

.nav.scrolled {
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: var(--max-content-width);
    margin: 0 auto;
    padding: var(--spacing-sm) var(--spacing-md);
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: var(--nav-height);
}

.nav-logo {
    flex-shrink: 0;
}

.logo {
    width: clamp(80px, 15vw, 120px);
    height: auto;
}

.nav-menu {
    display: flex;
    gap: var(--spacing-md);
    align-items: center;
}

.nav-link {
    font-size: clamp(0.875rem, 1.5vw, 1.125rem);
    font-weight: bold;
    letter-spacing: 1px;
    padding: var(--spacing-xs) var(--spacing-sm);
    transition: color var(--transition-fast);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%) scaleX(0);
    width: 80%;
    height: 2px;
    background: var(--color-primary);
    transition: transform var(--transition-fast);
}

.nav-link:hover,
.nav-link:focus {
    color: var(--color-primary);
}

.nav-link:hover::after,
.nav-link:focus::after {
    transform: translateX(-50%) scaleX(1);
}

/* Hamburger Menu */
.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    padding: 0;
    background: transparent;
    border: none;
    cursor: pointer;
    z-index: 1001;
}

.hamburger,
.hamburger::before,
.hamburger::after {
    width: 30px;
    height: 3px;
    background: var(--color-black);
    transition: all var(--transition-medium);
}

.hamburger {
    position: relative;
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    left: 0;
}

.hamburger::before {
    top: -8px;
}

.hamburger::after {
    bottom: -8px;
}

.nav-toggle[aria-expanded="true"] .hamburger {
    background: transparent;
}

.nav-toggle[aria-expanded="true"] .hamburger::before {
    top: 0;
    transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .hamburger::after {
    bottom: 0;
    transform: rotate(-45deg);
}

/* ========================================
   4. HERO SECTION
   ======================================== */
.hero {
    min-height: 60vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl) var(--spacing-md);
    background: var(--color-white);
}

.hero-content {
    text-align: center;
    max-width: 1000px;
}

.hero-title {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.hero-title-main {
    font-size: var(--font-size-h1);
    font-weight: bold;
    letter-spacing: clamp(2px, 0.5vw, 5px);
    color: var(--color-primary);
    line-height: 1.1;
}

.hero-title-sub {
    font-size: clamp(1.5rem, 3vw, 2.5rem);
    font-weight: bold;
    letter-spacing: clamp(1px, 0.3vw, 3px);
    color: var(--color-black);
}

/* ========================================
   5. CONTAINER
   ======================================== */
.container {
    max-width: var(--max-content-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ========================================
   6. SERVICIOS SECTION
   ======================================== */
.services {
    padding: var(--spacing-xl) 0;
    background: var(--color-white);
}

.services-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

.service-card {
    padding: var(--spacing-md);
    border: var(--border-width) solid var(--color-black);
    transition: all var(--transition-medium);
    background: var(--color-white);
}

.service-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-primary);
}

.service-icon {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: var(--spacing-sm);
    color: var(--color-primary);
}

.service-title {
    font-size: var(--font-size-h2);
    font-weight: bold;
    letter-spacing: 1px;
    margin-bottom: var(--spacing-sm);
    color: var(--color-black);
}

.service-desc {
    font-size: var(--font-size-body);
    color: var(--color-gray);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

.service-link {
    display: inline-block;
    font-size: var(--font-size-body);
    font-weight: bold;
    color: var(--color-primary);
    letter-spacing: 1px;
    transition: transform var(--transition-fast);
}

.service-link:hover {
    transform: translateX(4px);
}

/* ========================================
   7. HERRAMIENTAS SECTION
   ======================================== */
.tools-section {
    padding: var(--spacing-xl) 0;
    background: var(--color-gray-light);
    text-align: center;
}

.section-title {
    font-size: var(--font-size-h1);
    font-weight: bold;
    letter-spacing: 2px;
    margin-bottom: var(--spacing-md);
    color: var(--color-black);
}

.section-desc {
    font-size: clamp(1rem, 2vw, 1.25rem);
    color: var(--color-gray);
    margin-bottom: var(--spacing-lg);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.cta-button {
    display: inline-block;
    padding: clamp(0.75rem, 2vw, 1rem) clamp(1.5rem, 3vw, 2.5rem);
    background: var(--color-primary);
    color: var(--color-white);
    font-size: var(--font-size-body);
    font-weight: bold;
    letter-spacing: 1px;
    border: var(--border-width) solid var(--color-primary);
    transition: all var(--transition-fast);
}

.cta-button:hover,
.cta-button:focus {
    background: var(--color-white);
    color: var(--color-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* ========================================
   8. CONTACTO SECTION
   ======================================== */
.contact-section {
    padding: var(--spacing-xl) 0;
    background: var(--color-white);
}

.contact-intro {
    font-size: clamp(1rem, 2vw, 1.25rem);
    color: var(--color-gray);
    margin-bottom: var(--spacing-lg);
    text-align: center;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

/* Formulario de Contacto */
.contact-form {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-lg);
    border: var(--border-width) solid var(--color-black);
    background: var(--color-white);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.form-label {
    font-size: var(--font-size-body);
    font-weight: bold;
    color: var(--color-black);
    letter-spacing: 0.5px;
}

.form-input,
.form-textarea {
    padding: clamp(0.75rem, 2vw, 1rem);
    font-size: var(--font-size-body);
    font-family: var(--font-family);
    border: var(--border-width) solid var(--color-black);
    background: var(--color-white);
    transition: all var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(220, 0, 0, 0.1);
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: var(--color-gray);
}

.form-textarea {
    resize: vertical;
    min-height: 150px;
}

.form-checkbox-label {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    cursor: pointer;
    font-size: var(--font-size-small);
    color: var(--color-gray);
}

.form-checkbox {
    width: 20px;
    height: 20px;
    margin-top: 2px;
    cursor: pointer;
    accent-color: var(--color-primary);
}

.form-link {
    color: var(--color-primary);
    text-decoration: underline;
    transition: opacity var(--transition-fast);
}

.form-link:hover {
    opacity: 0.8;
}

.form-submit {
    width: 100%;
    margin-top: var(--spacing-md);
}

.form-error {
    font-size: var(--font-size-small);
    color: var(--color-primary);
    display: none;
    margin-top: var(--spacing-xs);
}

.form-error.active {
    display: block;
}

.form-input.error,
.form-textarea.error {
    border-color: var(--color-primary);
    background: rgba(220, 0, 0, 0.05);
}

.form-message {
    margin-top: var(--spacing-md);
    padding: var(--spacing-sm);
    border: var(--border-width) solid transparent;
    text-align: center;
    font-weight: bold;
    display: none;
}

.form-message.success {
    display: block;
    border-color: #00AA00;
    background: rgba(0, 170, 0, 0.1);
    color: #00AA00;
}

.form-message.error {
    display: block;
    border-color: var(--color-primary);
    background: rgba(220, 0, 0, 0.1);
    color: var(--color-primary);
}

/* Tarjeta destacada de Herramientas */
.service-card-featured {
    border-color: var(--color-primary);
    background: rgba(220, 0, 0, 0.02);
}

.service-card-featured:hover {
    background: rgba(220, 0, 0, 0.05);
}

/* ========================================
   9. FOOTER
   ======================================== */
.footer {
    background: var(--color-black);
    color: var(--color-white);
    padding: var(--spacing-xl) 0 var(--spacing-md);
    border-top: var(--border-width) solid var(--color-primary);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.footer-section {
    text-align: left;
}

.footer-title {
    font-size: clamp(1rem, 2vw, 1.25rem);
    font-weight: bold;
    letter-spacing: 1px;
    margin-bottom: var(--spacing-sm);
    color: var(--color-primary);
}

.footer-desc {
    font-size: var(--font-size-small);
    color: var(--color-gray);
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.footer-links a {
    font-size: var(--font-size-small);
    color: var(--color-white);
    transition: color var(--transition-fast);
}

.footer-links a:hover,
.footer-links a:focus {
    color: var(--color-primary);
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--color-gray);
    font-size: var(--font-size-small);
    color: var(--color-gray);
}

/* ========================================
   10. RESPONSIVE - MOBILE FIRST
   ======================================== */

/* Tablet: 768px */
@media (min-width: 768px) {
    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }

    /* Formulario en 2 columnas */
    .form-row {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Desktop: 1024px */
@media (min-width: 1024px) {
    .services-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .footer-content {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* Large Desktop: 1440px+ */
@media (min-width: 1440px) {
    :root {
        --spacing-xl: 8rem;
    }
}

/* Mobile: < 768px */
@media (max-width: 767px) {
    .nav-toggle {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: var(--nav-height);
        left: -100%;
        width: 80%;
        max-width: 300px;
        height: calc(100vh - var(--nav-height));
        background: var(--color-white);
        flex-direction: column;
        align-items: flex-start;
        padding: var(--spacing-md);
        gap: var(--spacing-sm);
        transition: left var(--transition-medium);
        box-shadow: var(--shadow-lg);
        overflow-y: auto;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-link {
        width: 100%;
        padding: var(--spacing-sm) 0;
        border-bottom: 1px solid var(--color-gray-light);
    }

    .nav-link::after {
        display: none;
    }

    .hero {
        min-height: 50vh;
        padding: var(--spacing-lg) var(--spacing-md);
    }

    /* Formulario mobile */
    .contact-form {
        padding: var(--spacing-md);
    }
}

/* Small Mobile: < 480px */
@media (max-width: 479px) {
    :root {
        --spacing-md: 1.5rem;
        --spacing-lg: 3rem;
    }

    .service-card {
        padding: var(--spacing-sm);
    }
}

/* ========================================
   11. ACCESIBILIDAD
   ======================================== */

/* Focus visible para teclado */
:focus-visible {
    outline: 3px solid var(--color-primary);
    outline-offset: 2px;
}

/* Reducir movimiento para usuarios con preferencias */
@media (prefers-reduced-motion: reduce) {

    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* Alto contraste */
@media (prefers-contrast: high) {
    :root {
        --color-gray: #333333;
    }

    .service-card {
        border-width: 3px;
    }
}

/* ========================================
   12. OPTIMIZACIONES PERFORMANCE
   ======================================== */

/* Lazy loading hint */
img[loading="lazy"] {
    content-visibility: auto;
}

/* GPU acceleration para animaciones */
.service-card,
.nav-link,
.cta-button {
    will-change: transform;
}

/* Contain layout para mejor rendering */
.service-card {
    contain: layout style paint;
}

/* ========================================
   13. PRINT STYLES
   ======================================== */
@media print {

    .nav,
    .nav-toggle,
    .footer {
        display: none;
    }

    .hero,
    .services,
    .tools-section,
    .contact-section {
        page-break-inside: avoid;
    }

    a[href]::after {
        content: " (" attr(href) ")";
    }
}