:root {
    --primary-color: #004D40;
    --primary-light: #00695C;
    --secondary-color: #FFC107;
    --bg-color: #F8F9FA;
    --surface-color: #FFFFFF;
    --text-main: #212529;
    --text-muted: #6C757D;
    --border-color: #DEE2E6;
    --border-radius: 4px;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    line-height: 1.5;
}

.navbar {
    background-color: var(--primary-color) !important;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.navbar-brand {
    font-weight: 700;
    letter-spacing: -0.5px;
}

.card {
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    transition: transform 0.2s;
}

.btn-primary {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    border-radius: var(--border-radius);
    font-weight: 600;
}

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

.table {
    background-color: var(--surface-color);
    border-radius: var(--border-radius);
    overflow: hidden;
}

.table th {
    background-color: #F1F3F5;
    text-transform: uppercase;
    font-size: 0.75rem;
    letter-spacing: 0.05em;
    font-weight: 700;
    color: var(--text-muted);
    border-bottom: 2px solid var(--border-color);
}

.attendance-toggle {
    cursor: pointer;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
    transition: all 0.2s;
}

.attendance-toggle.present {
    background-color: #E8F5E9;
    color: #2E7D32;
    border: 1px solid #A5D6A7;
}

.attendance-toggle.absent {
    background-color: #FFEBEE;
    color: #C62828;
    border: 1px solid #EF9A9A;
}

.stats-card {
    border-left: 4px solid var(--primary-color);
}

.stats-card h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0;
}

.stats-card p {
    color: var(--text-muted);
    font-size: 0.875rem;
    margin: 0;
}