:root {
    --bg-principal: #0a090e;
    --bg-card: rgba(20, 18, 26, 0.65);
    --neon-cyan: #00f2fe;
    --neon-purple: #4facfe;
    --texto-principal: #ffffff;
    --texto-secundario: #a0aec0;
    --borde-glow: rgba(79, 172, 254, 0.3);
}

*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

body {
    background-color: var(--bg-principal);
    /* Fondo con un patrón sutil de malla cyberpunk */
    background-image:
        radial-gradient(at 50% 0%, rgba(79, 172, 254, 0.15) 0px, transparent 50%),
        linear-gradient(rgba(255, 255, 255, 0.005) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.005) 1px, transparent 1px);
    background-size: 100% 100%, 25px 25px, 25px 25px;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    padding: 20px;
}

.login-container {
    width: 100%;
    max-width: 450px;
    perspective: 1000px;
}

.login-box {
    background: var(--bg-card);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-top: 1px solid var(--borde-glow);
    border-radius: 16px;
    padding: 40px 35px;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5), 
                0 0 40px rgba(79, 172, 254, 0.05);
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.login-box:hover {
    transform: translateY(-5px);
    box-shadow: 0 25px 60px rgba(0, 0, 0, 0.6), 
                0 0 50px rgba(0, 242, 254, 0.3);
    border-color: rgba(0, 242, 254, 0.3);
}

.logo {
    max-width: 220px;
    height: auto;
    margin-bottom: 25px;
    filter: drop-shadow(0px 4px 1px rgba(255, 255, 255, 0.9));
    transition: filter 0.3s ease;
}

.login-box:hover .logo {
    filter: drop-shadow(0px 8px 25px rgba(0, 242, 254, 0.25));
}

h2 {
    color: var(--texto-principal);
    font-size: 1.8rem;
    font-weight: 600;
    letter-spacing: 1px;
    margin-bottom: 30px;
    text-transform: uppercase;
    background: linear-gradient(135deg, var(--texto-principal) 30%, var(--texto-secundario));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Manejo de alertas del sistema */
.login-box center, 
.login-box .alert {
    margin-bottom: 20px;
    font-size: 0.95rem;
}

.input-group {
    position: relative;
    margin-bottom: 25px;
    text-align: left;
}

.input-group label {
    display: block;
    color: var(--texto-secundario);
    font-size: 0.85rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 8px;
    transition: color 0.3s ease;
}

.input-group input {
    width: 100%;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 8px;
    padding: 14px 16px;
    color: var(--texto-principal);
    font-size: 1rem;
    outline: none;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.input-group input:focus {
    border-color: var(--neon-cyan);
    background: rgba(0, 0, 0, 0.6);
    box-shadow: 0 0 15px rgba(0, 242, 254, 0.15), 
                inset 0 0 10px rgba(0, 242, 254, 0.05);
}

/* Animación para levantar el texto del label al enfocar */
.input-group input:focus + label,
.input-group:focus-within label {
    color: var(--neon-cyan);
}

.btn-login {
    width: 100%;
    background: linear-gradient(135deg, var(--neon-purple) 0%, var(--neon-cyan) 100%);
    border: none;
    border-radius: 8px;
    padding: 15px;
    color: #000000;
    font-size: 1rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0, 242, 254, 0.2);
    margin-top: 5px;
}

.btn-login:hover {
    transform: scale(1.02);
    box-shadow: 0 6px 20px rgba(0, 242, 254, 0.4);
    filter: brightness(1.1);
}

.btn-login:active {
    transform: scale(0.98);
}

.user-welcome {
    color: #fff;
    font-size: 0.9rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    background: linear-gradient(135deg, #ffffff 40%, var(--texto-secundario, #a0aec0));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.1);
    
}

/* Ajuste fino para pantallas pequeñas */
@media (max-width: 480px) {
    .login-box {
        padding: 30px 20px;
    }
    h2 {
        font-size: 1.5rem;
    }
}