/* === public/css/login.css === */
/* Versión Responsiva Optimizada */

/* ========================================
   1. VARIABLES CSS (Custom Properties)
   ======================================== */
:root {
    --color-primary: #007bff;
    --color-primary-dark: #0056b3;
    --color-primary-darker: #004d99;
    --color-secondary: #ffc107;
    --color-secondary-dark: #e0a800;
    --color-text: #343a40;
    --color-text-light: #6c757d;
    --color-bg: #e6f0ff;
    --color-white: #ffffff;
    --color-border: #ced4da;
    
    --border-radius-sm: 8px;
    --border-radius-md: 9px;
    --border-radius-lg: 20px;
    
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-md: 15px;
    --spacing-lg: 20px;
    --spacing-xl: 25px;
    --spacing-2xl: 40px;
    --spacing-3xl: 50px;
    
    --shadow-card: 0 10px 30px rgba(0, 0, 0, 0.1);
    --shadow-focus: 0 0 0 0.25rem rgba(0, 123, 255, 0.25);
    
    --font-size-base: 1rem;
    --font-size-lg: 1.1rem;
    --font-size-xl: 1.15rem;
    --font-size-2xl: 1.9rem;
}

/* ========================================
   2. RESET Y BASE
   ======================================== */
* {
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--color-bg);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    padding: 1rem;
    background-color: white;
}

/* ========================================
   3. TARJETA PRINCIPAL
   ======================================== */
.card-login {
    background-color: var(--color-white);
    border: 2px solid var(--color-primary);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-card);
    padding: var(--spacing-3xl) var(--spacing-2xl);
    width: 100%;
    max-width: 400px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

/* Efecto hover sutil en desktop */
@media (hover: hover) {
    .card-login:hover {
        transform: translateY(-2px);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.15);
    }
}

/* ========================================
   4. AVATAR Y TÍTULO
   ======================================== */
.icono-avatar {
    color: var(--color-primary);
    border: 3px solid var(--color-primary);
    border-radius: 50%;
    padding: var(--spacing-xs);
    background-color: var(--color-white);
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.titulo-login {
    color: var(--color-text);
    font-weight: 700;
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-2xl);
    font-size: var(--font-size-2xl);
    line-height: 1.2;
}

/* ========================================
   5. FORMULARIO
   ======================================== */
.label-login {
    font-weight: 600;
    color: var(--color-text);
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-xs);
    font-size: var(--font-size-lg);
}

.icono-label {
    margin-right: var(--spacing-xs);
    color: var(--color-primary);
    flex-shrink: 0;
}

/* ========================================
   6. INPUTS
   ======================================== */
.usuario,
.contrasena {
    width: 100%;
    margin-bottom: var(--spacing-lg);
}

.form-control {
    width: 100%;
    border-radius: var(--border-radius-md);
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--color-border);
    font-size: var(--font-size-lg);
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
    background-color: var(--color-white);
}

.form-control:focus {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-focus);
    outline: none;
}

/* ========================================
   7. INPUT GROUP (Campo con botón)
   ======================================== */
.input-group {
    width: 100%;
    display: flex;
    margin-bottom: var(--spacing-xl);
}

.input-group .form-control {
    flex: 1;
    border-top-right-radius: 0;
    border-bottom-right-radius: 0;
    margin-bottom: 0;
}

.input-group .btn-outline-secondary {
    border: 1px solid var(--color-border);
    border-left: none;
    border-top-right-radius: var(--border-radius-sm);
    border-bottom-right-radius: var(--border-radius-sm);
    color: var(--color-text-light);
    background-color: var(--color-white);
    padding: var(--spacing-sm) var(--spacing-md);
    cursor: pointer;
    transition: background-color 0.3s ease, color 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.input-group .btn-outline-secondary:hover {
    background-color: #f8f9fa;
    color: var(--color-text);
}

/* ========================================
   8. BOTONES
   ======================================== */
.btn-acceder,
.btn-regresar {
    width: 100%;
    display: block;
    text-align: center;
    font-weight: 700;
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-sm) 0;
    font-size: var(--font-size-xl);
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
}

.btn-acceder {
    background-color: var(--color-primary);
    color: var(--color-white);
    margin-bottom: 10px;
}

.btn-acceder:hover,
.btn-acceder:focus {
    background-color: var(--color-primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 123, 255, 0.3);
}

.btn-acceder:active {
    transform: translateY(0);
}

.btn-regresar {
    background-color: var(--color-secondary);
    color: var(--color-text);
}

.btn-regresar:hover,
.btn-regresar:focus {
    background-color: var(--color-secondary-dark);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(255, 193, 7, 0.3);
}

.btn-regresar:active {
    transform: translateY(0);
}

/* ========================================
   9. MEDIA QUERIES - RESPONSIVIDAD
   ======================================== */

/* Tablets (pantallas medianas) */
@media (max-width: 768px) {
    :root {
        --font-size-2xl: 1.6rem;
        --font-size-lg: 1rem;
        --font-size-xl: 1.05rem;
        --spacing-3xl: 35px;
        --spacing-2xl: 30px;
    }
    
    .card-login {
        max-width: 500px;
        padding: var(--spacing-3xl) var(--spacing-2xl);
    }
}

/* Móviles grandes */
@media (max-width: 576px) {
    :root {
        --font-size-2xl: 1.5rem;
        --font-size-lg: 0.95rem;
        --font-size-xl: 1rem;
        --spacing-3xl: 30px;
        --spacing-2xl: 25px;
        --spacing-xl: 20px;
        --spacing-lg: 18px;
    }
    
    body {
        padding: 0.5rem;
    }
    
    .card-login {
        padding: var(--spacing-2xl) var(--spacing-lg);
        border-radius: var(--spacing-md);
    }
    
    .titulo-login {
        margin-bottom: var(--spacing-xl);
    }
}

/* Móviles pequeños */
@media (max-width: 380px) {
    :root {
        --font-size-2xl: 1.4rem;
        --font-size-lg: 0.9rem;
        --font-size-xl: 0.95rem;
        --spacing-3xl: 25px;
        --spacing-2xl: 20px;
    }
    
    .card-login {
        padding: var(--spacing-lg) var(--spacing-md);
    }
    
    .btn-acceder,
    .btn-regresar {
        padding: 10px 0;
    }
}

/* ========================================
   10. ACCESIBILIDAD
   ======================================== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Mejora del contraste para modo de alto contraste */
@media (prefers-contrast: high) {
    .card-login {
        border-width: 3px;
    }
    
    .form-control {
        border-width: 2px;
    }
    
    .btn-acceder,
    .btn-regresar {
        border: 2px solid currentColor;
    }
}

/* ========================================
   11. ESTADOS DE CARGA Y ERROR
   ======================================== */
.form-control.is-invalid {
    border-color: #dc3545;
}

.form-control.is-invalid:focus {
    box-shadow: 0 0 0 0.25rem rgba(220, 53, 69, 0.25);
}

.form-control:disabled {
    background-color: #e9ecef;
    opacity: 0.6;
    cursor: not-allowed;
}

/* ========================================
   12. UTILIDADES
   ======================================== */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}