:root {
    --primary-color: #007bff;
    --light-gray: #f8f9fa;
    --medium-gray: #e9ecef;
    --dark-gray: #6c757d;
    --text-color: #212529;
    --white-color: #ffffff;
    --card-shadow: 0 4px 8px rgba(0, 0, 0, 0.05);
    --card-hover-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
    --border-radius: 8px;
}

*, *::before, *::after {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--light-gray);
    color: var(--text-color);
    margin: 0;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: var(--white-color);
    padding: 1rem 2rem;
    border-bottom: 1px solid var(--medium-gray);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.04);
}

h1 {
    text-align: left;
    margin: 0;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary-color);
}

.view-switcher {
    display: flex;
    border: 1px solid var(--medium-gray);
    border-radius: 6px;
}

.view-btn {
    background-color: transparent;
    border: none;
    padding: 0.5rem;
    cursor: pointer;
    color: var(--dark-gray);
    display: flex;
    align-items: center;
    justify-content: center;
}

    .view-btn:first-child {
        border-radius: 6px 0 0 6px;
    }

    .view-btn:last-child {
        border-radius: 0 6px 6px 0;
    }

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

main {
    max-width: 1400px;
    margin: 2rem auto;
    padding: 0 2rem;
}

.controls-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    align-items: end;
    margin-bottom: 2.5rem;
    padding: 2rem;
    background-color: var(--white-color);
    border-radius: var(--border-radius);
    box-shadow: var(--card-shadow);
}

.control-group.wide-control {
    grid-column: span 2;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--dark-gray);
    font-size: 0.9rem;
}

input, select, button {
    font-family: inherit;
    font-size: 1rem;
}

    input[type="number"], select {
        width: 100%;
        padding: 0.5rem 0.75rem;
        border: 1px solid #ced4da;
        border-radius: 6px;
    }

.seed-input-group {
    display: flex;
}

    .seed-input-group input {
        border-radius: 6px 0 0 6px;
        border-right: none;
    }

    .seed-input-group button {
        padding: 0 12px;
        border: 1px solid #ced4da;
        background-color: #f8f9fa;
        cursor: pointer;
        border-radius: 0 6px 6px 0;
    }

.view-container {
    display: none;
}

    .view-container.active {
        display: block;
    }

#table-container {
    background-color: var(--white-color);
    border-radius: var(--border-radius);
    box-shadow: var(--card-shadow);
    overflow: hidden;
}

table {
    width: 100%;
    border-collapse: collapse;
}

th, td {
    padding: 1rem 1.5rem;
    text-align: left;
    border-bottom: 1px solid var(--medium-gray);
}

thead th {
    background-color: var(--light-gray);
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--dark-gray);
}

tbody tr {
    transition: background-color 0.2s ease;
}

    tbody tr:hover {
        background-color: #f0f2f5;
        cursor: pointer;
    }

    tbody tr:last-child td {
        border-bottom: none;
    }

#card-grid-container.active {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.book-card {
    background-color: var(--white-color);
    border-radius: var(--border-radius);
    box-shadow: var(--card-shadow);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    cursor: pointer;
}

    .book-card:hover {
        transform: translateY(-5px);
        box-shadow: var(--card-hover-shadow);
    }

.card-cover-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    background-color: var(--medium-gray);
}

.card-content {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.card-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin: 0 0 0.5rem 0;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.card-author {
    color: var(--dark-gray);
    font-size: 0.9rem;
    margin: 0;
    flex-grow: 1;
}

.modal {
    position: fixed;
    z-index: 1000;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.65);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s, visibility 0.2s;
}

    .modal.visible {
        opacity: 1;
        visibility: visible;
    }

.modal-content {
    background-color: var(--white-color);
    max-width: 580px;
    width: 100%;
    padding: 0;
    border-radius: var(--border-radius);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    transform: scale(0.95);
    transition: transform 0.2s ease;
    position: relative;
}

.modal.visible .modal-content {
    transform: scale(1);
}

.close-btn {
    position: absolute;
    top: 0.75rem;
    right: 1rem;
    font-size: 1.8rem;
    color: #adb5bd;
    cursor: pointer;
    line-height: 1;
    transition: color 0.2s;
    z-index: 10;
}

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

.modal-main-content {
    display: flex;
    padding: 1.5rem;
}

.modal-cover-wrapper {
    flex-shrink: 0;
    width: 130px;
    margin-right: 1.5rem;
}

    .modal-cover-wrapper img {
        width: 100%;
        height: auto;
        border-radius: 4px;
        box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
        display: block;
    }

.modal-details-wrapper {
    flex-grow: 1;
}

    .modal-details-wrapper h3 {
        font-size: 1.3rem;
        margin: 0 0 0.5rem 0;
        line-height: 1.3;
    }

    .modal-details-wrapper p {
        margin: 0.3rem 0;
        font-size: 0.9rem;
        color: #495057;
    }

        .modal-details-wrapper p strong {
            color: var(--text-color);
        }

.modal-reviews-container {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--medium-gray);
    background-color: var(--light-gray);
    max-height: 160px;
    overflow-y: auto;
}

    .modal-reviews-container h4 {
        margin: 0 0 1rem 0;
        font-size: 1rem;
        color: var(--dark-gray);
    }

.review-item {
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

    .review-item strong {
        display: block;
        margin-bottom: 0.25rem;
    }

    .review-item p {
        margin: 0;
        color: #495057;
        line-height: 1.4;
    }