* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Poppins', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #000000;
    min-height: 100vh;
    color: #ffffff;
    position: relative;
}

/* Fondo con Copa del Mundo - Versión mejorada */
body::before {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: url('../images/world-cup-trophy.png');
    background-size: 40%;
    background-position: center;
    background-repeat: no-repeat;
    opacity: 0.15;
    pointer-events: none;
    z-index: 0;
}

/* Degradado oscuro para mejorar legibilidad */
body::after {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at center, rgba(0,0,0,0.7) 0%, rgba(0,0,0,0.95) 100%);
    pointer-events: none;
    z-index: 1;
}

.container {
    position: relative;
    z-index: 2;
    max-width: 1400px;
    margin: 0 auto;
    padding: 40px 20px;
}

/* Tarjetas y contenedores con efecto vidrio oscuro */
.card, form, .grupo-card, .feature, .info-mundial {
    background: rgba(20, 20, 20, 0.9);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.5);
    padding: 40px;
    margin-bottom: 30px;
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid rgba(255,215,0,0.2);
}

.grupo-card:hover, .feature:hover {
    transform: translateY(-5px);
    box-shadow: 0 30px 70px rgba(0,0,0,0.6);
    border-color: rgba(255,215,0,0.5);
}

/* Títulos con efecto dorado */
h1 {
    font-size: 3em;
    text-align: center;
    margin-bottom: 20px;
    background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

h2 {
    font-size: 2em;
    color: #FFD700;
    margin-bottom: 30px;
    text-align: center;
    border-bottom: 3px solid #FFD700;
    display: inline-block;
    padding-bottom: 10px;
}

h3 {
    font-size: 1.5em;
    color: #FFD700;
    margin-bottom: 15px;
}

/* Formularios */
form {
    max-width: 500px;
    margin: 0 auto;
}

label {
    display: block;
    margin-bottom: 8px;
    color: #FFD700;
    font-weight: 600;
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

input, select, textarea {
    width: 100%;
    padding: 14px;
    margin-bottom: 20px;
    border: 2px solid #333;
    border-radius: 12px;
    font-size: 16px;
    transition: all 0.3s;
    font-family: inherit;
    background: #1a1a1a;
    color: #ffffff;
}

input:focus, select:focus, textarea:focus {
    outline: none;
    border-color: #FFD700;
    box-shadow: 0 0 0 3px rgba(255,215,0,0.2);
}

/* Botones */
button, .btn-primary, .btn-secondary, .btn-whatsapp, .btn-volver {
    display: inline-block;
    padding: 14px 30px;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    text-decoration: none;
    text-align: center;
    font-family: inherit;
}

button, .btn-primary {
    background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
    color: #000000;
    width: 100%;
    font-weight: bold;
}

button:hover, .btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(255,215,0,0.4);
}

.btn-secondary {
    background: transparent;
    color: #FFD700;
    border: 2px solid #FFD700;
}

.btn-secondary:hover {
    background: #FFD700;
    color: #000000;
    transform: translateY(-2px);
}

.btn-whatsapp {
    background: linear-gradient(135deg, #25D366 0%, #128C7E 100%);
    color: white;
    font-size: 18px;
    padding: 15px 40px;
}

.btn-whatsapp:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(37,211,102,0.4);
}

.btn-volver {
    background: #333333;
    color: white;
    margin-left: 10px;
}

.btn-volver:hover {
    background: #444444;
    transform: translateY(-2px);
}

/* Menú de navegación */
.menu {
    background: rgba(0, 0, 0, 0.8);
    padding: 20px;
    border-radius: 15px;
    margin-bottom: 40px;
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    justify-content: center;
    border: 1px solid rgba(255,215,0,0.3);
}

.menu a {
    color: #FFD700;
    text-decoration: none;
    padding: 10px 20px;
    border-radius: 10px;
    transition: all 0.3s;
    font-weight: 600;
}

.menu a:hover {
    background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
    color: #000000;
    transform: translateY(-2px);
}

/* Grid de grupos */
.grupos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.grupo-card {
    background: rgba(20, 20, 20, 0.95);
    padding: 25px;
    border-radius: 15px;
    position: relative;
    overflow: hidden;
}

.grupo-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 5px;
    background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
}

.grupo-card h3 {
    font-size: 28px;
    text-align: center;
    margin-bottom: 20px;
}

.grupo-card p {
    margin: 12px 0;
    font-size: 16px;
    color: #cccccc;
    display: flex;
    align-items: center;
    gap: 10px;
}

.grupo-card a {
    display: inline-block;
    margin-top: 15px;
    padding: 8px 20px;
    background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
    color: #000000;
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.3s;
    text-align: center;
    font-weight: bold;
}

.grupo-card a:hover {
    transform: scale(1.05);
    box-shadow: 0 5px 15px rgba(255,215,0,0.3);
}

/* Hero section */
.hero {
    text-align: center;
    padding: 80px 20px;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(10px);
    border-radius: 30px;
    margin-bottom: 50px;
    border: 1px solid rgba(255,215,0,0.3);
}

.hero h1 {
    font-size: 4em;
    margin-bottom: 10px;
}

.hero h2 {
    font-size: 2em;
    border-bottom: none;
}

.hero p {
    font-size: 1.2em;
    color: #cccccc;
    margin-bottom: 30px;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
}

/* Features */
.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin: 50px 0;
}

.feature {
    text-align: center;
    padding: 30px;
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 20px;
}

.feature h3 {
    margin-bottom: 15px;
}

.feature p {
    color: #cccccc;
    line-height: 1.6;
}

/* Mensaje WhatsApp */
.mensaje-preview {
    background: #1a1a1a;
    padding: 25px;
    border-radius: 15px;
    margin: 20px 0;
    font-family: 'Courier New', monospace;
    border-left: 5px solid #25D366;
    font-size: 14px;
    line-height: 1.6;
    max-height: 400px;
    overflow-y: auto;
    color: #ffffff;
}

.pronostico-preview h3 {
    color: #FFD700;
    margin-bottom: 20px;
}

.acciones {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
    margin: 30px 0;
}

.info {
    background: rgba(255, 215, 0, 0.1);
    padding: 20px;
    border-radius: 12px;
    margin-top: 20px;
    text-align: center;
    border: 1px solid rgba(255,215,0,0.3);
}

.info p {
    margin: 10px 0;
    color: #FFD700;
}

/* Alertas */
.error {
    background: linear-gradient(135deg, #f44336 0%, #d32f2f 100%);
    color: white;
    padding: 12px 20px;
    border-radius: 10px;
    margin: 15px 0;
    text-align: center;
    font-weight: 600;
}

.success {
    background: linear-gradient(135deg, #4caf50 0%, #45a049 100%);
    color: white;
    padding: 12px 20px;
    border-radius: 10px;
    margin: 15px 0;
    text-align: center;
    font-weight: 600;
}

/* Links */
a {
    color: #FFD700;
    text-decoration: none;
    transition: all 0.3s;
}

a:hover {
    color: #FFA500;
}

/* Banderas */
.bandera-mini, .bandera-grupo {
    width: 40px;
    height: 30px;
    object-fit: cover;
    border-radius: 5px;
    border: 1px solid #FFD700;
    background: #1a1a1a;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 20px 15px;
    }
    
    h1 {
        font-size: 2em;
    }
    
    h2 {
        font-size: 1.5em;
    }
    
    .hero {
        padding: 40px 15px;
    }
    
    .hero h1 {
        font-size: 2.5em;
    }
    
    .grupos-grid {
        grid-template-columns: 1fr;
    }
    
    form, .card {
        padding: 25px;
    }
    
    .menu a {
        padding: 8px 15px;
        font-size: 14px;
    }
    
    .acciones {
        flex-direction: column;
    }
    
    .btn-volver, .btn-whatsapp {
        width: 100%;
        margin: 5px 0;
    }
    
    body::before {
        background-size: 80%;
    }
}

/* Animaciones */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.grupo-card, .feature, .hero {
    animation: fadeIn 0.6s ease-out;
}

/* Estilo para selectores */
select {
    cursor: pointer;
}

select option {
    background: #1a1a1a;
    color: #ffffff;
}

/* Footer */
footer {
    text-align: center;
    margin-top: 50px;
    padding: 20px;
    color: #888888;
}

/* Scrollbar personalizada */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: #1a1a1a;
}

::-webkit-scrollbar-thumb {
    background: #FFD700;
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: #FFA500;
}