/* ============================================================================
   Sistema de Matrículas — Estilos personalizados
   Complementa Bootstrap 4 con tokens de diseño consistentes.
   ============================================================================ */

:root {
    --color-primary: #0d6e3b;
    --color-primary-dark: #0a5530;
    --color-primary-light: #2d8b5a;
    --color-secondary: #f59e0b;
    --color-bg: #f4f7f5;
    --color-surface: #ffffff;
    --color-text: #1f2937;
    --color-text-muted: #6b7280;
    --color-border: #e5e7eb;
    --color-success: #16a34a;
    --color-error: #dc2626;
    --color-warning: #d97706;
    --color-info: #0284c7;

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;

    --shadow-sm: 0 1px 2px rgba(0,0,0,.05);
    --shadow-md: 0 4px 12px rgba(0,0,0,.08);
    --shadow-lg: 0 12px 32px rgba(0,0,0,.12);

    --space-1: 4px;
    --space-2: 8px;
    --space-3: 16px;
    --space-4: 24px;
    --space-5: 32px;
    --space-6: 48px;
}

* { box-sizing: border-box; }

body {
    background: var(--color-bg);
    color: var(--color-text);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.55;
}

a { color: var(--color-primary); text-decoration: none; }
a:hover { color: var(--color-primary-dark); text-decoration: underline; }

.app-shell {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ------ Navbar ------ */
.app-navbar {
    background: var(--color-primary);
    color: #fff;
    padding: 12px 24px;
    box-shadow: var(--shadow-sm);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
}
.app-navbar .brand {
    display: flex;
    align-items: center;
    gap: 12px;
    color: #fff;
    font-weight: 600;
    font-size: 1.05rem;
}
.app-navbar .brand img { height: 36px; }
.app-navbar .nav-actions { display: flex; gap: 16px; align-items: center; }
.app-navbar .nav-actions a {
    color: #fff;
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    transition: background .15s;
}
.app-navbar .nav-actions a:hover { background: rgba(255,255,255,.15); text-decoration: none; }

/* ------ Containers ------ */
.app-main {
    flex: 1;
    padding: var(--space-5) 0;
}
.app-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-3);
}

/* ------ Sidebar ------ */
.app-sidebar {
    background: var(--color-surface);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    padding: 12px 0;
}
.app-sidebar a {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 16px;
    color: var(--color-text);
    border-left: 3px solid transparent;
    transition: all .15s;
}
.app-sidebar a:hover {
    background: var(--color-bg);
    border-left-color: var(--color-primary-light);
    text-decoration: none;
}
.app-sidebar a.active {
    background: rgba(13,110,59,.08);
    border-left-color: var(--color-primary);
    color: var(--color-primary-dark);
    font-weight: 600;
}

/* ------ Cards ------ */
.app-card {
    background: var(--color-surface);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    padding: var(--space-4);
    margin-bottom: var(--space-4);
}
.app-card h2, .app-card h3 { margin-top: 0; }
.app-card-title {
    margin: 0 0 var(--space-3);
    padding-bottom: var(--space-2);
    border-bottom: 1px solid var(--color-border);
    color: var(--color-primary-dark);
    font-size: 1.25rem;
}

/* ------ KPI ------ */
.kpi-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: var(--space-3);
    margin-bottom: var(--space-4);
}
.kpi {
    background: var(--color-surface);
    border-radius: var(--radius-md);
    padding: var(--space-3);
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--color-primary);
}
.kpi .label { color: var(--color-text-muted); font-size: .85rem; text-transform: uppercase; letter-spacing: .5px; }
.kpi .value { font-size: 1.8rem; font-weight: 700; color: var(--color-primary-dark); margin-top: 4px; }

/* ------ Forms ------ */
.form-group label { font-weight: 600; color: var(--color-text); }
.form-control {
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
}
.form-control:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(13,110,59,.15);
}
.form-error { color: var(--color-error); font-size: .85rem; margin-top: 4px; display: block; }

/* ------ Buttons ------ */
.btn { border-radius: var(--radius-sm); font-weight: 600; padding: 8px 18px; }
.btn-primary {
    background: var(--color-primary);
    border-color: var(--color-primary);
}
.btn-primary:hover {
    background: var(--color-primary-dark);
    border-color: var(--color-primary-dark);
}
.btn-secondary {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    color: var(--color-text);
}
.btn-secondary:hover { background: var(--color-bg); }

/* ------ Alerts ------ */
.flash-stack {
    position: fixed;
    top: 16px;
    right: 16px;
    z-index: 9999;
    max-width: 360px;
    width: calc(100% - 32px);
}
.flash {
    padding: 12px 16px;
    border-radius: var(--radius-md);
    margin-bottom: 10px;
    box-shadow: var(--shadow-md);
    background: #fff;
    border-left: 4px solid var(--color-info);
    animation: slideIn .3s ease;
}
.flash-success { border-left-color: var(--color-success); }
.flash-error   { border-left-color: var(--color-error); }
.flash-info    { border-left-color: var(--color-info); }
@keyframes slideIn { from { opacity: 0; transform: translateX(20px); } to { opacity: 1; transform: none; } }

/* ------ Tables ------ */
.app-table {
    width: 100%;
    background: var(--color-surface);
    border-radius: var(--radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}
.app-table th {
    background: var(--color-primary);
    color: #fff;
    text-align: left;
    padding: 10px 14px;
    font-weight: 600;
}
.app-table td { padding: 10px 14px; border-bottom: 1px solid var(--color-border); }
.app-table tr:last-child td { border-bottom: 0; }
.app-table tr:hover td { background: var(--color-bg); }

/* ------ Search results card ------ */
.student-card {
    display: grid;
    grid-template-columns: 200px 1fr;
    gap: var(--space-4);
    background: var(--color-surface);
    border-radius: var(--radius-md);
    padding: var(--space-4);
    box-shadow: var(--shadow-md);
}
.student-card img {
    width: 100%;
    border-radius: var(--radius-md);
    object-fit: cover;
    aspect-ratio: 1;
    background: var(--color-bg);
}
@media (max-width: 640px) {
    .student-card { grid-template-columns: 1fr; }
}

/* ------ Hero ------ */
.hero {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    color: #fff;
    padding: var(--space-6) var(--space-4);
    border-radius: var(--radius-lg);
    text-align: center;
    margin-bottom: var(--space-4);
}
.hero h1 { font-size: 2rem; margin: 0 0 8px; }
.hero p { margin: 0; opacity: .9; }

/* ------ Status badges ------ */
.badge { display: inline-block; padding: 3px 10px; border-radius: 999px; font-size: .75rem; font-weight: 600; }
.badge-success { background: #dcfce7; color: #166534; }
.badge-warning { background: #fef3c7; color: #92400e; }
.badge-danger  { background: #fee2e2; color: #991b1b; }
.badge-info    { background: #dbeafe; color: #1e40af; }

/* ------ Footer ------ */
.app-footer {
    background: var(--color-surface);
    color: var(--color-text-muted);
    padding: var(--space-3);
    text-align: center;
    border-top: 1px solid var(--color-border);
}