body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 20px;
    background-color: #f5f5f5;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

h1, h2, h3 {
    color: #2c3e50;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

th, td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

th {
    background-color: #3498db;
    color: white;
}

tr:hover {
    background-color: #f5f5f5;
}

.button {
    display: inline-block;
    padding: 10px 15px;
    background: #3498db;
    color: white;
    text-decoration: none;
    border-radius: 4px;
    border: none;
    cursor: pointer;
    margin: 5px 0;
}

.button:hover {
    background: #2980b9;
}

.button-danger {
    background: #e74c3c;
}

.button-danger:hover {
    background: #c0392b;
}

.button-success {
    background: #2ecc71;
}

.button-success:hover {
    background: #27ae60;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}

.form-group input, .form-group select {
    width: 100%;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
    box-sizing: border-box;
}

.alert {
    padding: 10px 15px;
    border-radius: 4px;
    margin: 10px 0;
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-danger {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.nav {
    margin: 20px 0;
    padding: 10px 0;
    border-bottom: 1px solid #eee;
}

.nav a {
    margin-right: 15px;
    text-decoration: none;
    color: #3498db;
}

.nav a:hover {
    text-decoration: underline;
}

/* Dashboard Styles */
.dashboard {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 20px;
    margin: 40px 0;
}

.dashboard-button {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 200px;
    height: 200px;
    background-color: #3498db;
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-size: 20px;
    font-weight: bold;
    text-align: center;
    padding: 20px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    transition: transform 0.2s, background-color 0.2s;
}

.dashboard-button:hover {
    transform: translateY(-5px);
    background-color: #2980b9;
}

.dashboard-button i {
    font-size: 48px;
    margin-bottom: 15px;
}

/* Overlay Styles */
.overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.7);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.overlay-content {
    background-color: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 0 20px rgba(0,0,0,0.3);
    max-width: 500px;
    width: 90%;
    text-align: center;
}

.overlay-buttons {
    margin-top: 20px;
    display: flex;
    justify-content: center;
    gap: 15px;
}

.overlay-button {
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
    min-width: 100px;
}

.confirm-button {
    background-color: #2ecc71;
    color: white;
}

.cancel-button {
    background-color: #e74c3c;
    color: white;
}

.close-button {
    background-color: #3498db;
    color: white;
}

.result-icon {
    font-size: 48px;
    margin-bottom: 15px;
}

.success {
    color: #2ecc71;
}

.error {
    color: #e74c3c;
}

/* Book Form Styles */
.book-form { 
    background-color: #f9f9f9; 
    padding: 20px; 
    border-radius: 8px; 
    margin: 20px 0; 
}

.book-found { 
    background-color: #e6ffe6; 
    padding: 15px; 
    border-radius: 8px; 
    margin: 15px 0; 
}

/* Vorhandene Styles bleiben erhalten */

/* Responsive Design */
@media (max-width: 768px) {
    /* Allgemeine Anpassungen */
    body {
        padding: 10px;
        font-size: 14px;
    }
    
    .container {
        padding: 15px;
    }
    
    h1 {
        font-size: 24px;
    }
    
    /* Navigation */
    .nav {
        display: flex;
        flex-direction: column;
        padding: 5px 0;
    }
    
    .nav a {
        margin: 5px 0;
        padding: 8px;
        background-color: #f0f0f0;
        border-radius: 4px;
        text-align: center;
    }
    
    /* Dashboard */
    .dashboard {
        gap: 10px;
    }
    
    .dashboard-button {
        width: calc(50% - 10px);
        height: 150px;
        font-size: 16px;
        padding: 15px;
    }
    
    /* Tabellen */
    table {
        display: block;
        overflow-x: auto;
    }
    
    /* Formulare */
    .form-group input, .form-group select {
        padding: 10px;
    }
    
    /* Overlays */
    .overlay-content {
        width: 95%;
        padding: 15px;
    }
    
    .overlay-button {
        padding: 8px 15px;
        font-size: 14px;
    }
    
    /* Buchformulare */
    .book-form, .book-found {
        padding: 15px;
    }
}

@media (max-width: 480px) {
    /* Kleine Bildschirme */
    .dashboard-button {
        width: 100%;
        height: 130px;
        font-size: 15px;
    }
    
    /* Navigation */
    .nav a {
        font-size: 14px;
    }
    
    /* Tabellen */
    th, td {
        padding: 8px;
        font-size: 13px;
    }
    
    /* Overlays */
    .overlay-content {
        padding: 10px;
    }
    
    .overlay-buttons {
        flex-direction: column;
        gap: 10px;
    }
    
    .overlay-button {
        width: 100%;
        margin: 2px 0;
    }
    
    /* Formulargruppen */
    .form-group {
        margin-bottom: 10px;
    }
    
    /* Dashboard */
    .dashboard {
        margin: 20px 0;
    }
    
    /* Bestand-Tabelle Fußzeile */
    table tfoot tr td {
        font-size: 12px;
    }
}

/* Scrollbar für Tabellen auf mobilen Geräten */
.table-container {
    overflow-x: auto;
    margin-bottom: 20px;
}


/* Vorhandene Styles... */

/* Mobile Overlay-Optimierung */
@media (max-width: 768px) {
    .overlay-content {
        width: 95%;
        padding: 15px;
    }
    
    .overlay-buttons {
        flex-direction: column;
    }
    
    .overlay-button {
        width: 100%;
        margin-bottom: 10px;
    }
    
    #saleBookDetails, #priceResultMessage {
        font-size: 14px;
    }
    
    .dashboard-button {
        width: 45%;
        margin: 5px;
    }
}

@media (max-width: 480px) {
    .dashboard-button {
        width: 100%;
    }
    
    .overlay-content {
        padding: 10px;
    }
    
    .form-group input {
        padding: 12px;
        font-size: 16px;
    }
}