:root {
    --primary: #1e3a8a;
    --primary-light: #3b82f6;
    --primary-dark: #172554;
    --accent: #0ea5e9;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --bg-body: #f8fafc;
    --bg-card: #ffffff;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --border: #e2e8f0;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-body);
    color: var(--text-main);
    line-height: 1.5;
}

/* Navbar */
.navbar {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
    color: #ffffff;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.navbar .brand {
    font-size: 1.35rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    letter-spacing: -0.025em;
}

.nav-links {
    display: flex;
    gap: 1.25rem;
    list-style: none;
}

.nav-links a {
    color: #cbd5e1;
    text-decoration: none;
    font-weight: 500;
    padding: 0.4rem 0.8rem;
    border-radius: 6px;
    transition: all 0.2s ease;
}

.nav-links a:hover, .nav-links a.active {
    color: #ffffff;
    background: rgba(255, 255, 255, 0.15);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1.5rem;
}

/* Stat Cards */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1.25rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.25rem 1.5rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.stat-card .label {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.stat-card .value {
    font-size: 2rem;
    font-weight: 700;
    margin-top: 0.25rem;
    color: var(--text-main);
}

.stat-card .icon-pill {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

.icon-blue { background: #eff6ff; color: #2563eb; }
.icon-green { background: #ecfdf5; color: #059669; }
.icon-amber { background: #fffbeb; color: #d97706; }
.icon-purple { background: #f5f3ff; color: #7c3aed; }

/* Content Cards */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.5rem;
    margin-bottom: 2rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.25rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border);
}

.card-title {
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--text-main);
}

/* Tables */
.table-responsive {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.925rem;
}

th, td {
    padding: 0.75rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

th {
    background: #f1f5f9;
    color: var(--text-muted);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.75rem;
    letter-spacing: 0.05em;
}

tr:hover td {
    background: #f8fafc;
}

/* Badges */
.badge {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    padding: 0.25rem 0.65rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-present { background: #dcfce7; color: #15803d; }
.badge-late { background: #fef3c7; color: #b45309; }
.badge-halfday { background: #e0f2fe; color: #0369a1; }
.badge-absent { background: #fee2e2; color: #b91c1c; }
.badge-mode { background: #f1f5f9; color: #475569; border: 1px solid #cbd5e1; }

/* Buttons & Inputs */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    background: var(--primary);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    font-size: 0.875rem;
    font-weight: 500;
    text-decoration: none;
    border: none;
    cursor: pointer;
    transition: background 0.15s;
}

.btn:hover {
    background: var(--primary-light);
}

.btn-secondary {
    background: #e2e8f0;
    color: #334155;
}
.btn-secondary:hover {
    background: #cbd5e1;
}

.input-control {
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 0.875rem;
    color: var(--text-main);
    outline: none;
}
.input-control:focus {
    border-color: var(--primary-light);
}

/* Form layout */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 1rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
}

.form-group label {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-muted);
}