/* ============================================
   UNIVERSOVET - ESTILOS CSS
   Landing Page para Clínica Veterinaria
   ============================================ */

/* ============================================
   1. VARIABLES CSS (Custom Properties)
   ============================================ */
:root {
    /* Colores principales */
    --color-primary: #1a3a4a;          /* Azul petróleo oscuro */
    --color-primary-light: #2d5a6e;    /* Azul petróleo claro */
    --color-primary-dark: #0f252f;     /* Azul muy oscuro */
    
    --color-secondary: #4db6ac;        /* Verde azulado / Teal */
    --color-secondary-light: #80cbc4;  /* Verde azulado claro */
    --color-secondary-dark: #26a69a;   /* Verde azulado oscuro */
    
    --color-accent: #7ec8e3;           /* Celeste suave */
    --color-accent-light: #b3e0f2;     /* Celeste muy claro */
    
    /* Neutros */
    --color-white: #ffffff;
    --color-gray-50: #f8fafb;
    --color-gray-100: #f1f5f7;
    --color-gray-200: #e2e8eb;
    --color-gray-300: #cdd6db;
    --color-gray-400: #9ba8af;
    --color-gray-500: #6b7c85;
    --color-gray-600: #4a5960;
    --color-gray-700: #374248;
    --color-gray-800: #252e32;
    --color-gray-900: #1a2124;
    
    /* Tipografía */
    --font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', 
                   Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    
    --font-size-xs: 0.75rem;    /* 12px */
    --font-size-sm: 0.875rem;   /* 14px */
    --font-size-base: 1rem;     /* 16px */
    --font-size-lg: 1.125rem;   /* 18px */
    --font-size-xl: 1.25rem;    /* 20px */
    --font-size-2xl: 1.5rem;    /* 24px */
    --font-size-3xl: 1.875rem;  /* 30px */
    --font-size-4xl: 2.25rem;   /* 36px */
    --font-size-5xl: 3rem;      /* 48px */
    --font-size-6xl: 3.75rem;   /* 60px */
    
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    --line-height-tight: 1.2;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;
    
    /* Espaciado */
    --spacing-xs: 0.25rem;   /* 4px */
    --spacing-sm: 0.5rem;    /* 8px */
    --spacing-md: 1rem;      /* 16px */
    --spacing-lg: 1.5rem;    /* 24px */
    --spacing-xl: 2rem;      /* 32px */
    --spacing-2xl: 3rem;     /* 48px */
    --spacing-3xl: 4rem;     /* 64px */
    --spacing-4xl: 6rem;     /* 96px */
    
    /* Bordes */
    --border-radius-sm: 0.375rem;  /* 6px */
    --border-radius-md: 0.5rem;    /* 8px */
    --border-radius-lg: 0.75rem;   /* 12px */
    --border-radius-xl: 1rem;      /* 16px */
    --border-radius-2xl: 1.5rem;   /* 24px */
    --border-radius-full: 9999px;
    
    /* Sombras */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 
                 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 
                 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 
                 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    
    /* Transiciones */
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;
    
    /* Z-index */
    --z-dropdown: 100;
    --z-header: 200;
    --z-modal: 300;
    
    /* Contenedor */
    --container-max-width: 1200px;
    --container-padding: var(--spacing-md);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-normal);
    line-height: var(--line-height-normal);
    color: var(--color-gray-700);
    background-color: var(--color-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

ul, ol {
    list-style: none;
}

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

/* ============================================
   3. UTILIDADES
   ============================================ */
.container {
    width: 100%;
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* ============================================
   4. HEADER / NAVEGACIÓN
   ============================================ */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: var(--z-header);
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    transition: all var(--transition-normal);
}

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

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav__logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-weight: var(--font-weight-bold);
    font-size: var(--font-size-xl);
    color: var(--color-primary);
}

.logo__icon {
    font-size: var(--font-size-2xl);
}

.logo__text {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Menú hamburguesa */
.nav__toggle {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    padding: var(--spacing-sm);
    z-index: var(--z-modal);
}

.hamburger {
    position: relative;
    width: 24px;
    height: 2px;
    background-color: var(--color-primary);
    transition: var(--transition-fast);
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    left: 0;
    width: 24px;
    height: 2px;
    background-color: var(--color-primary);
    transition: var(--transition-fast);
}

.hamburger::before {
    top: -7px;
}

.hamburger::after {
    top: 7px;
}

/* Hamburguesa activa */
.nav__toggle--active .hamburger {
    background-color: transparent;
}

.nav__toggle--active .hamburger::before {
    top: 0;
    transform: rotate(45deg);
}

.nav__toggle--active .hamburger::after {
    top: 0;
    transform: rotate(-45deg);
}

/* Menú móvil */
.nav__menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 300px;
    height: 100vh;
    padding: 100px var(--spacing-xl) var(--spacing-xl);
    background-color: var(--color-white);
    box-shadow: var(--shadow-2xl);
    transition: right var(--transition-normal);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.nav__menu--open {
    right: 0;
}

.nav__link {
    display: block;
    padding: var(--spacing-sm) 0;
    font-weight: var(--font-weight-medium);
    color: var(--color-gray-600);
    transition: color var(--transition-fast);
}

.nav__link:hover {
    color: var(--color-primary);
}

.nav__link--cta {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    background-color: var(--color-secondary);
    color: var(--color-white);
    border-radius: var(--border-radius-full);
    margin-top: var(--spacing-md);
}

.nav__link--cta:hover {
    background-color: var(--color-secondary-dark);
    color: var(--color-white);
}

/* ============================================
   5. HERO SECTION
   ============================================ */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 100px var(--spacing-md) var(--spacing-2xl);
    background: linear-gradient(135deg, var(--color-gray-50) 0%, var(--color-white) 50%, var(--color-accent-light) 100%);
    overflow: hidden;
}

/* Formas decorativas */
.hero__background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    overflow: hidden;
}

.hero__shape {
    position: absolute;
    border-radius: 50%;
    opacity: 0.4;
}

.hero__shape--1 {
    top: -10%;
    right: -15%;
    width: 400px;
    height: 400px;
    background: linear-gradient(135deg, var(--color-secondary-light), var(--color-accent));
    animation: float 8s ease-in-out infinite;
}

.hero__shape--2 {
    bottom: -5%;
    left: -10%;
    width: 300px;
    height: 300px;
    background: linear-gradient(135deg, var(--color-accent), var(--color-secondary-light));
    animation: float 10s ease-in-out infinite reverse;
}

.hero__shape--3 {
    top: 40%;
    left: 50%;
    width: 150px;
    height: 150px;
    background: linear-gradient(135deg, var(--color-primary-light), var(--color-secondary));
    animation: float 6s ease-in-out infinite;
    opacity: 0.2;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0) rotate(0deg);
    }
    50% {
        transform: translateY(-20px) rotate(5deg);
    }
}

.hero__content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
}

.hero__badge {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-md);
    background-color: var(--color-white);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--border-radius-full);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-gray-600);
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
}

.hero__title {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-bold);
    line-height: var(--line-height-tight);
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.hero__title--highlight {
    display: block;
    background: linear-gradient(135deg, var(--color-secondary), var(--color-secondary-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero__subtitle {
    font-size: var(--font-size-lg);
    color: var(--color-gray-500);
    margin-bottom: var(--spacing-xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero__actions {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    align-items: center;
}

.hero__scroll {
    position: absolute;
    bottom: var(--spacing-xl);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--color-gray-400);
    font-size: var(--font-size-sm);
    animation: bounce 2s ease-in-out infinite;
}

.hero__scroll-icon {
    font-size: var(--font-size-xl);
}

@keyframes bounce {
    0%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    50% {
        transform: translateX(-50%) translateY(10px);
    }
}

/* ============================================
   6. BOTONES
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-semibold);
    border-radius: var(--border-radius-full);
    transition: all var(--transition-normal);
    cursor: pointer;
    border: 2px solid transparent;
}

.btn--primary {
    background-color: var(--color-secondary);
    color: var(--color-white);
    box-shadow: var(--shadow-md), 0 0 0 0 rgba(77, 182, 172, 0.4);
}

.btn--primary:hover {
    background-color: var(--color-secondary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), 0 0 0 4px rgba(77, 182, 172, 0.2);
}

.btn--secondary {
    background-color: transparent;
    color: var(--color-primary);
    border-color: var(--color-gray-300);
}

.btn--secondary:hover {
    background-color: var(--color-gray-100);
    border-color: var(--color-primary);
}

.btn--large {
    padding: var(--spacing-lg) var(--spacing-2xl);
    font-size: var(--font-size-lg);
}

.btn--whatsapp {
    background: linear-gradient(135deg, #25D366, #128C7E);
    color: var(--color-white);
}

.btn--whatsapp:hover {
    background: linear-gradient(135deg, #128C7E, #075E54);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn__icon {
    font-size: 1.2em;
}

/* ============================================
   7. SECCIONES - ESTILOS COMUNES
   ============================================ */
.section__header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto var(--spacing-3xl);
}

.section__badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-md);
    background-color: var(--color-secondary-light);
    color: var(--color-primary);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    border-radius: var(--border-radius-full);
    margin-bottom: var(--spacing-md);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.section__title {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
    line-height: var(--line-height-tight);
}

.section__description {
    font-size: var(--font-size-base);
    color: var(--color-gray-500);
    line-height: var(--line-height-relaxed);
}

/* ============================================
   8. FEATURES SECTION (Por qué elegirnos)
   ============================================ */
.features {
    padding: var(--spacing-4xl) 0;
    background-color: var(--color-white);
}

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

.feature-card {
    padding: var(--spacing-xl);
    background-color: var(--color-gray-50);
    border-radius: var(--border-radius-xl);
    text-align: center;
    transition: all var(--transition-normal);
    border: 1px solid var(--color-gray-100);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-secondary-light);
}

.feature-card__icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--color-secondary-light), var(--color-accent-light));
    border-radius: var(--border-radius-lg);
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-2xl);
}

.feature-card__title {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    color: var(--color-primary);
    margin-bottom: var(--spacing-sm);
}

.feature-card__description {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
    line-height: var(--line-height-relaxed);
}

/* ============================================
   9. SERVICES SECTION
   ============================================ */
.services {
    padding: var(--spacing-4xl) 0;
    background: linear-gradient(180deg, var(--color-gray-50) 0%, var(--color-white) 100%);
}

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

.service-card {
    position: relative;
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    background-color: var(--color-white);
    border-radius: var(--border-radius-lg);
    border: 1px solid var(--color-gray-200);
    transition: all var(--transition-normal);
    overflow: hidden;
}

.service-card:hover {
    border-color: var(--color-secondary);
    box-shadow: var(--shadow-md);
}

.service-card:hover .service-card__number {
    color: var(--color-secondary);
}

.service-card__number {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-gray-200);
    line-height: 1;
    transition: color var(--transition-normal);
}

.service-card__content {
    flex: 1;
}

.service-card__icon {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-xs);
    display: block;
}

.service-card__title {
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-semibold);
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
}

.service-card__description {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
    line-height: var(--line-height-normal);
}

/* ============================================
   10. TRUST SECTION (Confianza)
   ============================================ */
.trust {
    position: relative;
    padding: var(--spacing-4xl) 0;
    background-color: var(--color-primary);
    overflow: hidden;
}

.trust__background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

.trust__pattern {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: radial-gradient(circle at 20% 50%, rgba(77, 182, 172, 0.15) 0%, transparent 50%),
                      radial-gradient(circle at 80% 50%, rgba(126, 200, 227, 0.15) 0%, transparent 50%);
}

.trust__content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}

.trust__icon {
    font-size: var(--font-size-4xl);
    margin-bottom: var(--spacing-lg);
    display: block;
    opacity: 0.8;
}

.trust__quote {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-medium);
    color: var(--color-white);
    line-height: var(--line-height-relaxed);
    margin-bottom: var(--spacing-lg);
    font-style: italic;
}

.trust__author {
    font-size: var(--font-size-sm);
    color: var(--color-secondary-light);
    font-weight: var(--font-weight-medium);
}

/* ============================================
   11. CTA SECTION
   ============================================ */
.cta {
    padding: var(--spacing-4xl) 0;
    background: linear-gradient(180deg, var(--color-white) 0%, var(--color-gray-50) 100%);
}

.cta__content {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.cta__title {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
}

.cta__description {
    font-size: var(--font-size-base);
    color: var(--color-gray-500);
    margin-bottom: var(--spacing-xl);
}

.cta__note {
    margin-top: var(--spacing-lg);
    font-size: var(--font-size-sm);
    color: var(--color-gray-400);
}

/* ============================================
   12. FOOTER
   ============================================ */
.footer {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-primary-dark);
    color: var(--color-gray-400);
}

.footer__content {
    text-align: center;
}

.footer__copyright {
    font-size: var(--font-size-sm);
    margin-bottom: var(--spacing-xs);
}

.footer__tagline {
    font-size: var(--font-size-xs);
    color: var(--color-gray-500);
}

/* ============================================
   13. SCROLL TO TOP BUTTON
   ============================================ */
.scroll-top {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    width: 50px;
    height: 50px;
    background-color: var(--color-primary);
    color: var(--color-white);
    border-radius: var(--border-radius-full);
    font-size: var(--font-size-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-normal);
    z-index: var(--z-dropdown);
}

.scroll-top--visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.scroll-top:hover {
    background-color: var(--color-secondary);
    transform: translateY(-3px);
}

/* ============================================
   14. ANIMACIONES DE ENTRADA
   ============================================ */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in--visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   15. RESPONSIVE - TABLET (768px+)
   ============================================ */
@media (min-width: 768px) {
    :root {
        --container-padding: var(--spacing-xl);
    }
    
    /* Navegación */
    .nav__toggle {
        display: none;
    }
    
    .nav__menu {
        position: static;
        flex-direction: row;
        width: auto;
        height: auto;
        padding: 0;
        background: none;
        box-shadow: none;
        gap: var(--spacing-lg);
    }
    
    .nav__link--cta {
        margin-top: 0;
    }
    
    /* Hero */
    .hero__title {
        font-size: var(--font-size-4xl);
    }
    
    .hero__subtitle {
        font-size: var(--font-size-xl);
    }
    
    .hero__actions {
        flex-direction: row;
        justify-content: center;
    }
    
    /* Section titles */
    .section__title {
        font-size: var(--font-size-3xl);
    }
    
    /* Features grid */
    .features__grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    /* Services grid */
    .services__grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    /* Trust */
    .trust__quote {
        font-size: var(--font-size-2xl);
    }
    
    /* CTA */
    .cta__title {
        font-size: var(--font-size-3xl);
    }
}

/* ============================================
   16. RESPONSIVE - DESKTOP (1024px+)
   ============================================ */
@media (min-width: 1024px) {
    /* Hero */
    .hero {
        padding: 120px var(--spacing-xl) var(--spacing-3xl);
    }
    
    .hero__title {
        font-size: var(--font-size-5xl);
    }
    
    /* Features grid */
    .features__grid {
        grid-template-columns: repeat(4, 1fr);
    }
    
    /* Services - layout alternativo */
    .services__grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .service-card:last-child {
        grid-column: 2;
    }
}

/* ============================================
   17. RESPONSIVE - LARGE DESKTOP (1280px+)
   ============================================ */
@media (min-width: 1280px) {
    .hero__title {
        font-size: var(--font-size-6xl);
    }
    
    .section__title {
        font-size: var(--font-size-4xl);
    }
}

/* ============================================
   18. PREFERENCIAS DEL USUARIO
   ============================================ */
/* Reducir movimiento */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    html {
        scroll-behavior: auto;
    }
}

/* Modo oscuro (preparado para futuro) */
@media (prefers-color-scheme: dark) {
    /* Se puede implementar un tema oscuro aquí si se desea */
}