:root {
    --azul-oscuro: #1e3a8a;
    --azul-principal: #3b82f6;
    --azul-claro: #eff6ff;
    --fondo-gris: #f0f4f8;
}

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

body {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #1a2a4a, #1a6a8a);
}

.registro-card {
    background: white;
    border-radius: 16px;
    padding: 40px;
    width: 100%;
    max-width: 450px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}

.logo {
    text-align: center;
    margin-bottom: 30px;
}

.logo h1 {
    font-size: 26px;
    color: #1a6a8a;
    font-weight: 700;
}

.logo p {
    font-size: 13px;
    color: #888;
    margin-top: 4px;
}

.form-group {
    margin-bottom: 18px;
}

label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: #444;
    margin-bottom: 6px;
}

input {
    width: 100%;
    padding: 12px 14px;
    border: 1.5px solid #ddd;
    border-radius: 8px;
    font-size: 14px;
    transition: border-color 0.2s;
    outline: none;
}

input:focus {
    border-color: #1a6a8a;
}

.btn-registro {
    width: 100%;
    padding: 13px;
    background: linear-gradient(135deg, #1a2a4a, #1a6a8a);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    margin-top: 8px;
    transition: opacity 0.2s;
}

.btn-registro:hover {
    opacity: 0.9;
}

.alerta {
    padding: 10px 14px;
    border-radius: 8px;
    font-size: 13px;
    margin-bottom: 20px;
    text-align: center;
}

.error {
    background: #fee2e2;
    color: #991b1b;
}

.exito {
    background: #dcfce7;
    color: #166534;
}

.login-link {
    text-align: center;
    margin-top: 20px;
    font-size: 13px;
    color: #888;
}

.login-link a {
    color: #1a6a8a;
    font-weight: 600;
    text-decoration: none;
}

.login-link a:hover {
    text-decoration: underline;
}