:root {
    --sky-blue: #8ecae6ff;
    --blue-green: #219ebcff;
    --prussian-blue: #023047ff;
    --selective-yellow: #ffb703ff;
    --ut-orange: #fb8500ff;
}

body {
    background-color: var(--sky-blue);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.container {
    max-width: 1200px;
    padding: 20px;
}

h1 {
    color: var(--prussian-blue);
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
    margin-bottom: 2rem !important;
}

.card {
    border: none;
    border-radius: 15px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    margin-bottom: 1.5rem;
    background: white;
    transition: transform 0.2s ease-in-out;
}

.card:hover {
    transform: translateY(-5px);
}

.card-header {
    background-color: var(--prussian-blue);
    color: white;
    border-radius: 15px 15px 0 0 !important;
    padding: 1rem;
}

.card-header h5 {
    margin: 0;
    font-weight: 600;
}

.card-body {
    padding: 1.5rem;
}

.stats {
    font-size: 1.2em;
    color: var(--prussian-blue);
}

.stats p {
    margin-bottom: 1rem;
    padding: 0.5rem;
    border-radius: 8px;
    background-color: rgba(142, 202, 230, 0.1);
}

.stats span {
    font-weight: 600;
    color: var(--blue-green);
}

#borrowReader, #returnReader {
    width: 100%;
    max-width: 400px;
    margin: 0 auto;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.btn {
    padding: 0.6rem 1.2rem;
    font-weight: 600;
    border-radius: 8px;
    transition: all 0.2s ease-in-out;
    margin: 0 5px;
}

.btn-primary {
    background-color: var(--blue-green);
    border-color: var(--blue-green);
}

.btn-primary:hover {
    background-color: var(--prussian-blue);
    border-color: var(--prussian-blue);
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: var(--sky-blue);
    border-color: var(--sky-blue);
    color: var(--prussian-blue);
}

.btn-secondary:hover {
    background-color: var(--prussian-blue);
    border-color: var(--prussian-blue);
    color: white;
}

.btn-success {
    background-color: var(--selective-yellow);
    border-color: var(--selective-yellow);
    color: var(--prussian-blue);
}

.btn-success:hover {
    background-color: var(--ut-orange);
    border-color: var(--ut-orange);
    color: white;
}

.btn-info {
    background-color: var(--sky-blue);
    border-color: var(--sky-blue);
    color: var(--prussian-blue);
}

.btn-info:hover {
    background-color: var(--blue-green);
    border-color: var(--blue-green);
    color: white;
}

.table {
    margin-bottom: 0;
}

.table th {
    background-color: var(--prussian-blue);
    color: white;
    font-weight: 600;
    border: none;
}

.table td {
    vertical-align: middle;
    border-color: rgba(0,0,0,0.05);
}

.table tbody tr:hover {
    background-color: rgba(142, 202, 230, 0.1);
}

@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .btn {
        margin: 5px;
        width: 100%;
    }
    
    .card {
        margin-bottom: 1rem;
    }
    
    .stats {
        font-size: 1.1em;
    }
}

/* Custom scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--sky-blue);
}

::-webkit-scrollbar-thumb {
    background: var(--blue-green);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--prussian-blue);
}