/* 
   ESTILOS.CSS V2.0 
   Rediseño Completo - Modern Glassmorphism & Vibrant UI
*/

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800&family=Inter:wght@300;400;500;600&display=swap');

:root {
    /* Brand Colors - Modern Sky Blue Palette */
    --primary: #0ea5e9;
    --primary-light: #38bdf8;
    --primary-dark: #0284c7;
    --primary-glow: rgba(14, 165, 233, 0.4);
    
    --secondary: #6366f1; /* Indigo touch for variety */
    --accent: #f43f5e; /* Rose accent */
    
    /* Backgrounds */
    --bg-main: #fafafa;
    --bg-alt: #f1f5f9;
    --surface: #ffffff;
    
    /* Text */
    --text-primary: #0f172a;
    --text-sec: #475569;
    --text-light: #94a3b8;
    
    /* Borders */
    --border-light: rgba(15, 23, 42, 0.08);
    --border-med: rgba(15, 23, 42, 0.15);
    
    /* Variables - Shadows */
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.05);
    --shadow-lg: 0 12px 32px rgba(0,0,0,0.08);
    --shadow-glow: 0 8px 24px var(--primary-glow);
    
    /* Structural */
    --nav-height: 80px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

/* Dark Mode Overrides */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-main: #0B1120;
        --bg-alt: #0f172a;
        --surface: #1e293b;
        
        --text-primary: #f8fafc;
        --text-sec: #cbd5e1;
        --text-light: #64748b;
        
        --border-light: rgba(255, 255, 255, 0.08);
        --border-med: rgba(255, 255, 255, 0.15);
        
        --shadow-md: 0 4px 12px rgba(0,0,0,0.3);
        --shadow-lg: 0 12px 32px rgba(0,0,0,0.4);
    }
}

/* =========================================================================
   RESET & BASICS
   ========================================================================= */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--nav-height); /* So anchors don't hide under sticky nav */
}

body {
    font-family: 'Inter', system-ui, sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Outfit', sans-serif;
    font-weight: 700;
    line-height: 1.2;
    color: var(--text-primary);
}

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

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

ul {
    list-style: none;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

.text-center { text-align: center; }
.w-full { width: 100%; }
.block { display: block; }
.relative { position: relative; }
.z-10 { z-index: 10; }

/* =========================================================================
   TYPOGRAPHY & UTILS
   ========================================================================= */
.section-padding {
    padding: 6rem 0;
}

.alt-bg {
    background-color: var(--bg-alt);
}

.section-subtitle {
    display: inline-block;
    color: var(--primary);
    font-family: 'Outfit', sans-serif;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    font-size: 0.85rem;
    margin-bottom: 0.75rem;
    background: rgba(14, 165, 233, 0.1);
    padding: 0.25rem 0.75rem;
    border-radius: 100px;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 1.25rem;
}

.section-desc {
    color: var(--text-sec);
    font-size: 1.15rem;
    max-width: 600px;
    margin: 0 auto 3rem auto;
}

/* =========================================================================
   BUTTONS
   ========================================================================= */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.75rem;
    font-family: 'Outfit', sans-serif;
    font-weight: 600;
    font-size: 1rem;
    border-radius: var(--radius-md);
    transition: var(--transition);
    cursor: pointer;
    border: none;
    gap: 0.5rem;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

.btn-lg {
    padding: 1rem 2.5rem;
    font-size: 1.125rem;
    border-radius: var(--radius-lg);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: white !important;
    box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 28px var(--primary-glow);
}

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

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

.btn-glass {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    backdrop-filter: blur(8px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-glass:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

/* =========================================================================
   NAVIGATION
   ========================================================================= */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--nav-height);
    background: rgba(255, 255, 255, 0.85); /* fallback */
    background: var(--surface);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border-light);
    z-index: 1000;
    transition: var(--transition);
}

@media (prefers-color-scheme: dark){
    .navbar {
        background: rgba(30, 41, 59, 0.85);
    }
}

.navbar.scrolled {
    box-shadow: var(--shadow-sm);
    height: 70px;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: 'Outfit', sans-serif;
    font-weight: 800;
    font-size: 1.4rem;
    color: var(--text-primary);
}

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: white;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    font-family: 'Outfit', sans-serif;
    font-weight: 500;
    color: var(--text-sec);
    position: relative;
    transition: var(--transition);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0%;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
    border-radius: 2px;
}

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

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

.ml-4 { margin-left: 1rem; }

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
}

/* =========================================================================
   HERO SECTION
   ========================================================================= */
.hero-section {
    position: relative;
    padding: calc(var(--nav-height) + 4rem) 0 8rem 0;
    overflow: hidden;
    background: var(--bg-main);
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 2;
}

.badge-hero {
    display: inline-block;
    padding: 0.35rem 1rem;
    background: rgba(14, 165, 233, 0.1);
    color: var(--primary);
    border-radius: 100px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    border: 1px solid rgba(14, 165, 233, 0.2);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    line-height: 1.1;
    margin-bottom: 1.5rem;
}

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

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-sec);
    margin-bottom: 2.5rem;
    max-width: 540px;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    align-items: center;
}

/* Glass & Abstract Visuals */
.hero-visual {
    position: relative;
    height: 500px;
    perspective: 1000px;
}

.glass-card {
    background: rgba(255, 255, 255, 0.6);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid rgba(255, 255, 255, 0.4);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
}

@media (prefers-color-scheme: dark){
    .glass-card {
        background: rgba(30, 41, 59, 0.6);
        border: 1px solid rgba(255,255,255,0.1);
    }
}

.visual-card {
    position: absolute;
    width: 320px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) rotateY(-10deg) rotateX(5deg);
    padding: 1.5rem;
    z-index: 2;
}

.card-header-visual .dots {
    display: flex;
    gap: 6px;
    margin-bottom: 1.5rem;
}

.dots span {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--border-med);
}

.line-ph {
    height: 12px;
    background: var(--border-light);
    border-radius: 6px;
    margin-bottom: 0.75rem;
}

.w-80 { width: 80%; }
.w-100 { width: 100%; }
.w-60 { width: 60%; }

.math-eq {
    background: var(--bg-alt);
    padding: 1rem;
    border-radius: var(--radius-md);
    text-align: center;
    margin: 1.5rem 0;
    font-family: monospace;
    font-size: 1.1rem;
    border: 1px solid var(--border-light);
}

.stat-card {
    position: absolute;
    bottom: 40px;
    right: -20px;
    padding: 1rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    border-radius: var(--radius-lg);
    z-index: 3;
    width: auto;
}

.stat-card h4 { font-size: 0.9rem; margin:0; color:var(--text-sec); }
.stat-card p { font-size: 1.1rem; font-weight:700; color:var(--text-primary); margin:0;}
.icon-success { color: #10b981; }

.float-animation {
    animation: float 6s ease-in-out infinite;
}

.float-animation-delayed {
    animation: float 6s ease-in-out 2s infinite;
}

@keyframes float {
    0% { transform: translate(-50%, -50%) translateY(0px) rotateY(-10deg) rotateX(5deg); }
    50% { transform: translate(-50%, -50%) translateY(-15px) rotateY(-10deg) rotateX(5deg); }
    100% { transform: translate(-50%, -50%) translateY(0px) rotateY(-10deg) rotateX(5deg); }
}

.hero-bg-shapes {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    z-index: 0;
    pointer-events: none;
}

.shape {
    position: absolute;
    filter: blur(80px);
    opacity: 0.5;
    z-index: 0;
}

.shape-1 {
    top: -10%; left: -10%;
    width: 500px; height: 500px;
    background: var(--primary-glow);
    border-radius: 50%;
}

.shape-2 {
    bottom: 10%; right: -5%;
    width: 600px; height: 600px;
    background: rgba(99, 102, 241, 0.2);
    border-radius: 50%;
}

/* =========================================================================
   CATEGORIES GRID SECTION
   ========================================================================= */
.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.cat-card-modern {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xl);
    padding: 2rem;
    display: flex;
    flex-direction: column;
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.cat-card-modern::before {
    content: '';
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    background: linear-gradient(135deg, transparent, rgba(14, 165, 233, 0.03));
    z-index: -1;
}

.cat-icon-wrapper {
    width: 64px; height: 64px;
    background: var(--bg-alt);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    margin-bottom: 1.5rem;
    transition: var(--transition);
}

.cat-content h3 {
    font-size: 1.4rem;
    margin-bottom: 0.5rem;
}

.cat-count {
    color: var(--text-sec);
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.9rem;
}

.cat-count .dot {
    width: 8px; height: 8px;
    background: #10b981;
    border-radius: 50%;
    display: inline-block;
}

.cat-arrow {
    position: absolute;
    bottom: 2rem;
    right: 2rem;
    color: var(--text-light);
    transition: var(--transition);
    opacity: 0;
    transform: translateX(-10px);
}

.hover-lift {
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
}

.hover-lift:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-light);
}

.hover-lift:hover .cat-icon-wrapper {
    background: var(--primary);
    color: white;
    transform: scale(1.1);
}

.hover-lift:hover .cat-arrow {
    opacity: 1;
    transform: translateX(0);
    color: var(--primary);
}

/* =========================================================================
   COURSES SECTION
   ========================================================================= */
.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2.5rem;
}

.course-card {
    background: var(--surface);
    border-radius: var(--radius-xl);
    overflow: hidden;
    border: 1px solid var(--border-light);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.course-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-5px);
}

.course-img {
    height: 200px;
    background-size: cover;
    background-position: center;
    position: relative;
    padding: 1.25rem;
    display: flex;
    align-items: flex-start;
}

.course-badge {
    background: rgba(255, 255, 255, 0.9);
    color: #0f172a;
    padding: 0.25rem 0.75rem;
    border-radius: 100px;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
}

.course-badge.type-physics { color: #f59e0b; }
.course-badge.type-cs { color: #10b981; }

.course-body {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.course-title {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.course-desc {
    color: var(--text-sec);
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

.course-meta {
    display: flex;
    justify-content: space-between;
    border-top: 1px solid var(--border-light);
    padding-top: 1rem;
    margin-bottom: 1.5rem;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--text-light);
    font-size: 0.85rem;
    font-weight: 500;
}

/* =========================================================================
   CONTACT SECTION
   ========================================================================= */
.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.contact-details {
    margin-top: 2rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.c-icon {
    width: 48px; height: 48px;
    background: var(--bg-alt);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
}

.contact-item h5 { margin-bottom: 0.2rem; font-size: 1.1rem; }
.contact-item span { color: var(--text-sec); }

.glass-form {
    background: var(--surface);
    padding: 2.5rem;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-light);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    font-size: 0.95rem;
}

.form-control {
    width: 100%;
    padding: 0.85rem 1rem;
    border: 1px solid var(--border-med);
    border-radius: var(--radius-md);
    background: var(--bg-main);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.15);
}

/* =========================================================================
   FOOTER
   ========================================================================= */
.site-footer {
    background: #0B1120;
    color: #cbd5e1;
    padding: 5rem 0 2rem 0;
    position: relative;
    overflow: hidden;
}

.site-footer::before {
    content: '';
    position: absolute;
    top: 0; left: 0; width: 100%; height: 1px;
    background: linear-gradient(90deg, transparent, rgba(14, 165, 233, 0.5), transparent);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 4rem;
    margin-bottom: 4rem;
}

.text-white { color: white !important; }
.bg-white\/10 { background: rgba(255, 255, 255, 0.1) !important; box-shadow: none !important; }

.footer-desc {
    margin-top: 1rem;
    max-width: 300px;
    color: #94a3b8;
}

.footer-links-col h4 {
    color: white;
    margin-bottom: 1.5rem;
}

.footer-links-col ul li {
    margin-bottom: 0.75rem;
}

.footer-links-col a {
    color: #94a3b8;
    transition: var(--transition);
}

.footer-links-col a:hover {
    color: var(--primary);
    padding-left: 5px;
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 2rem;
    font-size: 0.9rem;
    color: #64748b;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    color: #94a3b8;
}

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

/* =========================================================================
   MOBILE RESPONSIVENESS
   ========================================================================= */
@media (max-width: 992px) {
    .hero-container { grid-template-columns: 1fr; text-align: center; }
    .hero-subtitle { margin: 0 auto 2rem auto; }
    .hero-cta { justify-content: center; }
    .hero-visual { display: none; /* simple opt for mobile hero */ }
    
    .contact-wrapper { grid-template-columns: 1fr; gap: 2rem; }
}

@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: var(--nav-height);
        left: 0; width: 100%;
        background: var(--surface);
        flex-direction: column;
        gap: 0;
        box-shadow: var(--shadow-md);
        clip-path: polygon(0 0, 100% 0, 100% 0, 0 0);
        transition: clip-path 0.4s ease-in-out;
    }
    .nav-links.show {
        clip-path: polygon(0 0, 100% 0, 100% 100%, 0% 100%);
    }
    .nav-link {
        padding: 1.25rem;
        display: block;
        width: 100%;
        text-align: center;
        border-bottom: 1px solid var(--border-light);
    }
    .mobile-menu-btn { display: block; }
    .ml-4 { margin: 1rem 0; width: 80%; text-align: center; }
    
    .footer-grid { grid-template-columns: 1fr; gap: 2rem; text-align: center; }
    .footer-desc { margin: 1rem auto; }
    .footer-links-col a:hover { padding-left: 0; }
    .footer-bottom { flex-direction: column; gap: 1rem; }
}

/* Utility Animations */
[data-animate="fade-up"] { opacity: 0; transform: translateY(20px); transition: all 0.8s ease-out; }
[data-animate="fade-up"].is-visible { opacity: 1; transform: translateY(0); }
[data-animate="fade-right"] { opacity: 0; transform: translateX(-20px); transition: all 0.8s ease-out; }
[data-animate="fade-right"].is-visible { opacity: 1; transform: translateX(0); }
[data-animate="fade-left"] { opacity: 0; transform: translateX(20px); transition: all 0.8s ease-out; }
[data-animate="fade-left"].is-visible { opacity: 1; transform: translateX(0); }
[data-animate="fade-in"] { opacity: 0; transition: all 1s ease-out; }
[data-animate="fade-in"].is-visible { opacity: 1; }
[data-animate="slide-up"] { opacity: 0; transform: translateY(40px); transition: all 1s cubic-bezier(0.25, 0.8, 0.25, 1); }
[data-animate="slide-up"].is-visible { opacity: 1; transform: translateY(0); }

/* VISTA INTERNA (Categoría y Ejercicio) */
.page-header {
    background: var(--bg-alt);
    padding: calc(var(--nav-height) + 3rem) 0 3rem 0;
    border-bottom: 1px solid var(--border-light);
    margin-bottom: 3rem;
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    color: var(--text-sec);
    margin-bottom: 1rem;
}

.breadcrumb a {
    color: var(--primary);
}

.breadcrumb svg { width: 14px; height: 14px; }

/* Acordeones de Temas (Nivel B) */
.theme-accordion {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    margin-bottom: 1rem;
    overflow: hidden;
    transition: var(--transition);
}

.theme-accordion.open {
    border-color: var(--primary-glow);
    box-shadow: var(--shadow-md);
}

.theme-header {
    padding: 1.25rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    background: var(--surface);
    transition: var(--transition);
}

.theme-header:hover {
    background: var(--bg-alt);
}

.theme-header h3 {
    margin: 0;
    font-size: 1.25rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.theme-header .acc-icon {
    color: var(--text-light);
    transition: transform 0.3s ease;
}

.theme-body {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease-out;
    background: var(--bg-main);
}

.theme-accordion.open .theme-body {
    max-height: 2000px; /* Arbitrary large number for expansion */
}

.exercise-list {
    display: flex;
    flex-direction: column;
}

.exercise-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 1.5rem;
    border-top: 1px solid var(--border-light);
    transition: var(--transition);
}

.exercise-item:hover {
    background: var(--surface);
}

.ex-info h4 {
    margin-bottom: 0.25rem;
    font-size: 1.1rem;
}

.ex-info p {
    color: var(--text-sec);
    font-size: 0.9rem;
    margin: 0;
}

/* Ver Ejercicio (Nivel C) */
.exercise-card {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xl);
    padding: 3rem;
    box-shadow: var(--shadow-sm);
    margin-bottom: 3rem;
}

.ex-meta-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-light);
}

.latex-container {
    font-size: 1.15rem;
    line-height: 1.8;
    color: var(--text-primary);
}

.latex-container p {
    margin-bottom: 1.5rem;
}

/* Auth Cards */
.auth-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-alt);
    background-image: radial-gradient(circle at 10% 20%, rgba(14, 165, 233, 0.05) 0%, transparent 20%);
    padding: 2rem;
}

.auth-card {
    background: var(--surface);
    padding: 3rem;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 440px;
    border: 1px solid var(--border-light);
}