/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --danger-color: #dc2626;
    --danger-hover: #b91c1c;
    --bg-color: #f9fafb;
    --card-bg: #ffffff;
    --text-color: #1f2937;
    --text-light: #6b7280;
    --border-color: #e5e7eb;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
header {
    background: var(--card-bg);
    padding: 20px;
    border-radius: 8px;
    box-shadow: var(--shadow);
    margin-bottom: 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

header h1 {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 0;
}

nav {
    display: flex;
    gap: 10px;
}

.nav-btn {
    padding: 10px 20px;
    background: transparent;
    border: 2px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    font-size: 1rem;
    color: var(--text-color);
    transition: all 0.2s;
}

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

.nav-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* Views */
.view {
    display: none;
}

.view.active {
    display: block;
}

.view-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 15px;
}

.view-header h2 {
    font-size: 1.75rem;
}

.filters {
    display: flex;
    gap: 10px;
}

.filters select,
.filters input {
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
}

.filters input {
    min-width: 200px;
}

/* Books Grid */
.books-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.book-card {
    background: var(--card-bg);
    border-radius: 8px;
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: transform 0.2s, box-shadow 0.2s;
}

.book-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.book-cover {
    width: 100%;
    height: 300px;
    overflow: hidden;
    background: var(--border-color);
}

.book-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.book-info {
    padding: 15px;
}

.book-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 5px;
    color: var(--text-color);
}

.book-author {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 10px;
}

.book-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
    font-size: 0.85rem;
}

.book-status {
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
}

.status-to_read {
    background: #e0e7ff;
    color: #4338ca;
}

.status-reading {
    background: #fef3c7;
    color: #92400e;
}

.status-finished {
    background: #d1fae5;
    color: #065f46;
}

.status-dropped {
    background: #fee2e2;
    color: #991b1b;
}

.book-rating {
    color: #fbbf24;
}

.book-actions {
    display: flex;
    gap: 8px;
}

/* Buttons */
.btn {
    padding: 8px 16px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: background-color 0.2s;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

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

.btn-sm {
    padding: 6px 12px;
    font-size: 0.85rem;
}

.btn-danger {
    background: var(--danger-color);
    color: white;
}

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

/* Forms */
.form-group {
    margin-bottom: 20px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
    color: var(--text-color);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    font-family: inherit;
}

.form-group textarea {
    resize: vertical;
}

/* Tabs */
.add-book-tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    border-bottom: 2px solid var(--border-color);
}

.tab-btn {
    padding: 10px 20px;
    background: transparent;
    border: none;
    border-bottom: 2px solid transparent;
    cursor: pointer;
    font-size: 1rem;
    color: var(--text-light);
    margin-bottom: -2px;
    transition: color 0.2s;
}

.tab-btn:hover {
    color: var(--text-color);
}

.tab-btn.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* Search */
#search-form {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

#search-form input {
    flex: 1;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
}

.search-results {
    display: grid;
    gap: 15px;
}

.search-result {
    display: flex;
    gap: 15px;
    background: var(--card-bg);
    padding: 15px;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.search-result img {
    width: 80px;
    height: 120px;
    object-fit: cover;
    border-radius: 4px;
}

.search-result-info {
    flex: 1;
}

.search-result-info h4 {
    margin-bottom: 5px;
}

.search-result-info .meta {
    color: var(--text-light);
    font-size: 0.9rem;
    margin: 5px 0;
}

/* Import/Export */
.import-section,
.export-section {
    background: var(--card-bg);
    padding: 20px;
    border-radius: 8px;
    box-shadow: var(--shadow);
    margin-bottom: 20px;
}

.import-section h3,
.export-section h3 {
    margin-bottom: 10px;
}

.import-section p,
.export-section p {
    color: var(--text-light);
    margin-bottom: 15px;
}

.import-section input[type="file"] {
    margin-bottom: 10px;
}

.import-result {
    margin-top: 15px;
    padding: 15px;
    border-radius: 6px;
}

.import-result .success {
    background: #d1fae5;
    color: #065f46;
}

.import-result .error {
    background: #fee2e2;
    color: #991b1b;
}

.import-result ul {
    margin-top: 10px;
    margin-left: 20px;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    overflow: auto;
}

.modal.hidden {
    display: none;
}

.modal:not(.hidden) {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--card-bg);
    margin: 20px;
    padding: 30px;
    border-radius: 8px;
    max-width: 800px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    position: relative;
}

.close-modal {
    position: absolute;
    right: 20px;
    top: 20px;
    font-size: 2rem;
    font-weight: bold;
    color: var(--text-light);
    cursor: pointer;
    line-height: 1;
}

.close-modal:hover {
    color: var(--text-color);
}

.book-detail-content {
    display: flex;
    gap: 30px;
}

.book-detail-cover {
    flex-shrink: 0;
}

.book-detail-cover img {
    width: 200px;
    height: 300px;
    object-fit: cover;
    border-radius: 4px;
}

.book-detail-info {
    flex: 1;
}

.book-detail-info h2 {
    margin-bottom: 10px;
}

.book-detail-author {
    color: var(--text-light);
    font-size: 1.1rem;
    margin-bottom: 15px;
}

.book-description {
    margin: 20px 0;
    padding: 15px;
    background: var(--bg-color);
    border-radius: 6px;
}

/* Utilities */
.hidden {
    display: none !important;
}

.loading {
    text-align: center;
    padding: 40px;
    color: var(--text-light);
}

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-light);
}

.error {
    padding: 15px;
    background: #fee2e2;
    color: #991b1b;
    border-radius: 6px;
    margin: 15px 0;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }

    header {
        flex-direction: column;
        align-items: flex-start;
    }

    nav {
        width: 100%;
        margin-top: 15px;
    }

    .nav-btn {
        flex: 1;
    }

    .books-grid {
        grid-template-columns: 1fr;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .book-detail-content {
        flex-direction: column;
    }

    .book-detail-cover {
        text-align: center;
    }
}