:root {
    --primary: #1B3A6B;
    --primary-rgb: 27, 58, 107;
    --primary-dark: #12294D;
    --primary-light: #2E5490;
    --secondary: #2E5490;
    --gold: #C9A227;
    --gold-rgb: 201, 162, 39;
    --gold-light: #E0BB4D;
    --success: #16A34A;
    --warning: #F59E0B;
    --danger: #DC2626;
    --bg: #F7F5F0;
    --card-bg: #FFFFFF;
    --text: #1E2A38;
    --text-muted: #5B6B7F;
    --border: #E5E0D5;
    --sidebar-bg: #0F2440;
    --sidebar-text: #C7D2DE;
    --sidebar-active: #C9A227;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
    --radius: 0.75rem;
}

[data-theme="dark"] {
    --bg: #10151F;
    --card-bg: #1A2436;
    --text: #E3E8EF;
    --text-muted: #93A0B4;
    --border: #2C3A50;
    --sidebar-bg: #0A1830;
    --sidebar-text: #93A0B4;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.4), 0 1px 2px rgba(0, 0, 0, 0.3);
}

* { box-sizing: border-box; }

body {
    background: var(--bg);
    color: var(--text);
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    font-size: 0.9375rem;
    transition: background-color 0.2s ease, color 0.2s ease;
}

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

.card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    color: var(--text);
}

.card-header {
    background: transparent;
    border-bottom: 1px solid var(--border);
    font-weight: 600;
}

/* Layout shell */
.app-shell { display: flex; min-height: 100vh; }

.sidebar {
    width: 260px;
    flex-shrink: 0;
    background: var(--sidebar-bg);
    color: var(--sidebar-text);
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    overflow-y: auto;
    z-index: 1030;
    transition: transform 0.25s ease;
    display: flex;
    flex-direction: column;
}

.sidebar-brand {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    gap: 0;
    padding: 1.25rem 1.25rem;
    color: #fff;
    font-weight: 700;
    font-size: 1.15rem;
    letter-spacing: 0.02em;
    border-bottom: 1px solid rgba(255,255,255,0.08);
}

.sidebar-brand .logo-dot { color: var(--gold); }

.sidebar-brand-subtitle {
    display: block;
    font-size: 0.7rem;
    font-weight: 400;
    letter-spacing: 0.03em;
    color: var(--sidebar-text);
    margin-top: 0.2rem;
}

.sidebar-logo-img { height: 136px; width: 136px; object-fit: contain; flex-shrink: 0; }

.login-logo-img { height: 108px; width: 108px; object-fit: contain; }

.sidebar-nav { padding: 0.75rem 0.75rem; flex-grow: 1; }

.sidebar-footer {
    padding: 0.9rem 1rem;
    border-top: 1px solid rgba(255,255,255,0.08);
    text-align: left;
    font-size: 0.7rem;
    line-height: 1.5;
    color: rgba(199, 210, 222, 0.55);
    flex-shrink: 0;
}

.sidebar-footer .sidebar-footer-version { color: var(--gold); font-weight: 600; }

.sidebar-nav-label {
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: rgba(199, 210, 222, 0.5);
    padding: 0.9rem 0.9rem 0.35rem;
}

.sidebar-nav .nav-link {
    color: var(--sidebar-text);
    padding: 0.6rem 0.9rem;
    border-radius: 0.5rem;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.7rem;
    margin-bottom: 0.15rem;
    transition: background-color 0.15s ease, color 0.15s ease;
}

.sidebar-nav .nav-link i { width: 1.1rem; text-align: center; }

.sidebar-nav .nav-link:hover { background: rgba(255,255,255,0.07); color: #fff; }

.sidebar-nav .nav-link.active {
    background: var(--sidebar-active);
    color: var(--primary-dark);
    font-weight: 600;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
}

.main-content {
    margin-left: 260px;
    flex-grow: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
}

.topbar {
    background: var(--card-bg);
    border-bottom: 3px solid var(--gold);
    padding: 0.75rem 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 1020;
}

.page-body { padding: 1.5rem; flex-grow: 1; }

.sidebar-toggle-btn { display: none; }

@media (max-width: 991.98px) {
    .sidebar { transform: translateX(-100%); }
    .sidebar.show { transform: translateX(0); }
    .main-content { margin-left: 0; }
    .sidebar-toggle-btn { display: inline-flex; }
    .sidebar-backdrop {
        display: none;
        position: fixed;
        inset: 0;
        background: rgba(0,0,0,0.4);
        z-index: 1025;
    }
    .sidebar-backdrop.show { display: block; }
}

/* Stat cards */
.stat-card {
    border-radius: var(--radius);
    padding: 1.25rem;
    color: #fff;
    box-shadow: var(--shadow);
}

.stat-card .stat-value { font-size: 1.75rem; font-weight: 700; }
.stat-card .stat-label { font-size: 0.85rem; opacity: 0.9; }
.stat-card .stat-icon { font-size: 1.75rem; opacity: 0.85; }

.bg-grad-primary { background: linear-gradient(135deg, #1B3A6B, #2E5490); }
.bg-grad-accent { background: linear-gradient(135deg, #C9A227, #E0BB4D); color: #2A1F00; }
.bg-grad-accent .stat-label { color: #2A1F00; opacity: 0.75; }
.bg-grad-warning { background: linear-gradient(135deg, #F59E0B, #FBBF24); }
.bg-grad-danger { background: linear-gradient(135deg, #DC2626, #F87171); }

.btn-primary { background: var(--primary); border-color: var(--primary); }
.btn-primary:hover { background: var(--primary-dark); border-color: var(--primary-dark); }
.btn-success { background: var(--success); border-color: var(--success); }
.btn-warning { background: var(--warning); border-color: var(--warning); color: #fff; }
.btn-warning:hover { color: #fff; }
.btn-danger { background: var(--danger); border-color: var(--danger); }

.btn-outline-primary { color: var(--primary); border-color: var(--primary); }
.btn-outline-primary:hover { background: var(--primary); border-color: var(--primary); color: #fff; }
.btn-outline-success { color: var(--success); border-color: var(--success); }
.btn-outline-success:hover { background: var(--success); border-color: var(--success); color: #fff; }
.btn-outline-danger { color: var(--danger); border-color: var(--danger); }
.btn-outline-danger:hover { background: var(--danger); border-color: var(--danger); color: #fff; }
.btn-outline-warning { color: #B45309; border-color: var(--warning); }
.btn-outline-warning:hover { background: var(--warning); border-color: var(--warning); color: #fff; }

.text-primary { color: var(--primary) !important; }
.text-success { color: var(--success) !important; }
.text-danger { color: var(--danger) !important; }
.text-warning { color: #B45309 !important; }
.text-info { color: var(--primary-light) !important; }

.nav-pills .nav-link.active { background: var(--primary) !important; color: #fff !important; }

.badge.text-bg-primary { background: var(--primary) !important; }
.badge.text-bg-success { background: var(--success) !important; }
.badge.text-bg-danger { background: var(--danger) !important; }
.badge.text-bg-warning { background: var(--warning) !important; color: #fff !important; }
.badge.text-bg-info { background: var(--primary-light) !important; color: #fff !important; }

.form-check-input:checked { background-color: var(--primary); border-color: var(--primary); }

.table { color: var(--text); }
.table > :not(caption) > * > * { background: transparent; color: var(--text); border-color: var(--border); }

.form-control, .form-select {
    background: var(--card-bg);
    color: var(--text);
    border-color: var(--border);
}
.form-control:focus, .form-select:focus {
    background: var(--card-bg);
    color: var(--text);
    border-color: var(--primary);
    box-shadow: 0 0 0 0.2rem rgba(var(--primary-rgb), 0.15);
}

.modal-content { background: var(--card-bg); color: var(--text); }

.badge-status-present { background: #16A34A; color: #fff; }
.badge-status-absent { background: #F97316; color: #fff; }
.badge-status-late { background: #EAB308; color: #1E293B; }
.badge-status-excused { background: #3B82F6; color: #fff; }

.attendance-row-present { background: rgba(22, 163, 74, 0.14); }
.attendance-row-absent { background: rgba(249, 115, 22, 0.14); }
.attendance-row-late { background: rgba(234, 179, 8, 0.16); }
.attendance-row-excused { background: rgba(59, 130, 246, 0.14); }

.btn-outline-orange { color: #F97316; border-color: #F97316; background: transparent; }
.btn-outline-orange:hover { color: #fff; background: #F97316; border-color: #F97316; }

.avatar-circle {
    width: 40px; height: 40px; border-radius: 50%;
    object-fit: cover; background: var(--border);
}

.login-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #12294D, #C9A227);
}

.login-card {
    width: 100%;
    max-width: 400px;
    border-radius: 1rem;
    box-shadow: 0 20px 40px rgba(0,0,0,0.25);
    background: rgba(255, 255, 255, 0.16);
    border: 1px solid rgba(255, 255, 255, 0.35);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    color: #fff;
}

.login-card .form-label { color: #fff; }
.login-card .login-plus { color: #fff; }
.login-card .text-muted { color: rgba(255, 255, 255, 0.75) !important; }
.login-card .form-control {
    background: rgba(255, 255, 255, 0.12);
    border-color: rgba(255, 255, 255, 0.35);
    color: #fff;
}
.login-card .form-control::placeholder { color: rgba(255, 255, 255, 0.55); }
.login-card .form-control:focus {
    background: rgba(255, 255, 255, 0.2);
    border-color: var(--gold);
    color: #fff;
    box-shadow: 0 0 0 0.2rem rgba(var(--gold-rgb), 0.25);
}

@media print {
    .sidebar, .topbar, .no-print { display: none !important; }
    .main-content { margin-left: 0 !important; }
}