/* Language Academy - Estilos Principales */

:root {
    --primary: #667eea;
    --secondary: #764ba2;
    --success: #28a745;
    --danger: #dc3545;
    --warning: #ffc107;
    --info: #17a2b8;
    --light: #f8f9fa;
    --dark: #343a40;
    --white: #ffffff;
    --gray: #6c757d;
    --gray-light: #f5f7fa;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 5px 20px rgba(0, 0, 0, 0.15);
    --border-radius: 8px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--gray-light);
    color: var(--dark);
    line-height: 1.6;
}

/* Tipografía */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    color: var(--dark);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.75rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1rem; }

p {
    margin-bottom: 1rem;
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--secondary);
    text-decoration: underline;
}

/* Botones */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
    font-size: 1rem;
    text-decoration: none;
    user-select: none;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: var(--white);
}

.btn-primary:hover:not(:disabled) {
    opacity: 0.9;
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background-color: var(--gray);
    color: var(--white);
}

.btn-secondary:hover:not(:disabled) {
    filter: brightness(0.9);
}

.btn-success {
    background-color: var(--success);
    color: var(--white);
}

.btn-success:hover:not(:disabled) {
    filter: brightness(0.9);
}

.btn-danger {
    background-color: var(--danger);
    color: var(--white);
}

.btn-danger:hover:not(:disabled) {
    filter: brightness(0.9);
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

.btn-block {
    width: 100%;
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--dark);
}

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-family: inherit;
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-control.is-invalid {
    border-color: var(--danger);
}

.invalid-feedback {
    display: block;
    color: var(--danger);
    font-size: 0.875rem;
    margin-top: 0.25rem;
}

textarea.form-control {
    resize: vertical;
    min-height: 120px;
}

/* Alertas */
.alert {
    padding: 1rem 1.25rem;
    margin-bottom: 1.5rem;
    border-radius: var(--border-radius);
    border-left: 4px solid;
}

.alert-primary {
    background-color: #e7f0ff;
    border-color: var(--primary);
    color: var(--primary);
}

.alert-success {
    background-color: #d4edda;
    border-color: var(--success);
    color: #155724;
}

.alert-danger {
    background-color: #f8d7da;
    border-color: var(--danger);
    color: #721c24;
}

.alert-warning {
    background-color: #fff3cd;
    border-color: var(--warning);
    color: #856404;
}

.alert-info {
    background-color: #d1ecf1;
    border-color: var(--info);
    color: #0c5460;
}

/* Cards */
.card {
    background-color: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.card-header {
    padding: 1.25rem;
    background-color: var(--gray-light);
    border-bottom: 1px solid #e0e0e0;
}

.card-body {
    padding: 1.25rem;
}

.card-footer {
    padding: 1.25rem;
    background-color: var(--gray-light);
    border-top: 1px solid #e0e0e0;
}

/* Grid */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.row {
    display: flex;
    flex-wrap: wrap;
    margin: 0 -0.5rem;
}

.col {
    padding: 0 0.5rem;
    flex: 1;
    min-width: 250px;
}

.col-12 { flex: 0 0 100%; }
.col-6 { flex: 0 0 50%; }
.col-4 { flex: 0 0 33.333%; }
.col-3 { flex: 0 0 25%; }

@media (max-width: 768px) {
    .col,
    .col-6,
    .col-4,
    .col-3 {
        flex: 0 0 100%;
    }
}

/* Navbar */
.navbar {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: var(--white);
    padding: 1rem 0;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.navbar-brand {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--white);
    text-decoration: none;
}

.navbar-nav {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.navbar-nav a {
    color: var(--white);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

.navbar-nav a:hover {
    opacity: 0.8;
}

/* Tablas */
.table {
    width: 100%;
    border-collapse: collapse;
    background-color: var(--white);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
}

.table thead {
    background-color: var(--gray-light);
}

.table th,
.table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid #e0e0e0;
}

.table th {
    font-weight: 600;
    color: var(--dark);
}

.table tbody tr:hover {
    background-color: #f9f9f9;
}

/* Badges */
.badge {
    display: inline-block;
    padding: 0.35rem 0.65rem;
    border-radius: 999px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-primary {
    background-color: #e7f0ff;
    color: var(--primary);
}

.badge-success {
    background-color: #d4edda;
    color: #155724;
}

.badge-danger {
    background-color: #f8d7da;
    color: #721c24;
}

.badge-warning {
    background-color: #fff3cd;
    color: #856404;
}

.badge-info {
    background-color: #d1ecf1;
    color: #0c5460;
}

/* Progress Bar */
.progress {
    width: 100%;
    height: 8px;
    background-color: #e0e0e0;
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 0.5rem;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    transition: width 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 0.75rem;
    font-weight: 600;
}

/* Modales */
.modal {
    display: none;
    position: fixed;
    z-index: 999;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    animation: fadeIn 0.3s;
}

.modal.show {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background-color: var(--white);
    padding: 2rem;
    border-radius: var(--border-radius);
    max-width: 600px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    animation: slideIn 0.3s;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    border-bottom: 1px solid #e0e0e0;
    padding-bottom: 1rem;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--gray);
}

.modal-close:hover {
    color: var(--dark);
}

/* Animaciones */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideIn {
    from {
        transform: translateY(-50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/* Spinner de carga */
.spinner {
    display: inline-block;
    width: 40px;
    height: 40px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Responsive */
@media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.5rem; }
    h3 { font-size: 1.25rem; }

    .navbar-nav {
        gap: 1rem;
        font-size: 0.875rem;
    }

    .container {
        padding: 0 0.5rem;
    }

    .modal-content {
        padding: 1.5rem;
    }
}

/* Utilidades */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mt-5 { margin-top: 3rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }
.mb-5 { margin-bottom: 3rem; }

.p-1 { padding: 0.5rem; }
.p-2 { padding: 1rem; }
.p-3 { padding: 1.5rem; }
.p-4 { padding: 2rem; }
.p-5 { padding: 3rem; }

.d-none { display: none; }
.d-inline { display: inline; }
.d-inline-block { display: inline-block; }
.d-block { display: block; }
.d-flex { display: flex; }
.d-grid { display: grid; }

.flex-center {
    display: flex;
    align-items: center;
    justify-content: center;
}

.flex-between {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.w-100 { width: 100%; }
.h-100 { height: 100%; }

.hidden { visibility: hidden; }
.invisible { opacity: 0; }