/* ======= Base Layout ======= */
:root {
    --primary-dark: #2C2416;
    --primary-brown: #5D4E37;
    --accent-gold: #C9A961;
    --background-cream: #FAF8F3;
    --background-light: #FFFFFF;
    --text-dark: #3E2723;
    --text-medium: #6D6D6D;
    --text-light: #9E9E9E;
    --border-color: #E8E3DA;
    --shadow-light: rgba(0, 0, 0, 0.08);
    --shadow-medium: rgba(0, 0, 0, 0.12);
}

body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f9f9f9;
}

.container {
    max-width: 1000px;
    margin: 40px auto;
    background: #fff;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

/* ======= Headings ======= */
header {
    background: var(--primary-dark);
    color: var(--background-cream);
    padding: 30px 50px;
    border-bottom: 3px solid var(--accent-gold);
}

header h1 {
    font-family: 'Georgia', serif;
    font-size: 2.8em;
    font-weight: normal;
    letter-spacing: 2px;
    margin-bottom: 15px;
    color: var(--accent-gold);
}

nav {
    display: flex;
    gap: 25px;
    align-items: center;
    flex-wrap: wrap;
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 0.95em;
}

nav a {
    color: var(--background-cream);
    text-decoration: none;
    padding: 8px 18px;
    border: 1px solid transparent;
    border-radius: 2px;
    transition: all 0.3s ease;
    letter-spacing: 0.5px;
}

nav a:hover {
    border-color: var(--accent-gold);
    background: rgba(201, 169, 97, 0.1);
}

nav span {
    margin-left: auto;
    display: flex;
    align-items: center;
    gap: 15px;
    font-size: 0.9em;
}

.btn-link {
    background: none;
    border: none;
    color: var(--background-cream);
    cursor: pointer;
    padding: 0;
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 0.9em;
    text-decoration: underline;
    text-decoration-color: var(--accent-gold);
    transition: all 0.3s ease;
}

.btn-link:hover {
    color: var(--accent-gold);
}

/* ======= Search and Filter ======= */
.search-section {
    background: var(--background-cream);
    padding: 30px;
    border-radius: 3px;
    margin-bottom: 40px;
    border: 1px solid var(--border-color);
}

.search-form {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    align-items: center;
}

.search-form input,
.search-form select {
    padding: 12px 18px;
    border: 1px solid var(--border-color);
    background: var(--background-light);
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 0.95em;
    color: var(--text-dark);
    transition: all 0.3s ease;
}

.search-form input {
    flex: 1;
    min-width: 250px;
}

.search-form input:focus,
.search-form select:focus {
    outline: none;
    border-color: var(--accent-gold);
    background: var(--background-cream);
}

/* ======= Buttons ======= */
.btn {
    background: var(--primary-brown);
    color: var(--background-cream);
    border: none;
    padding: 12px 30px;
    cursor: pointer;
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 0.95em;
    text-decoration: none;
    display: inline-block;
    transition: all 0.3s ease;
    letter-spacing: 0.5px;
    border: 1px solid var(--primary-brown);
}

.btn:hover {
    background: var(--primary-dark);
    border-color: var(--primary-dark);
    box-shadow: 0 4px 15px var(--shadow-medium);
}

.btn-secondary {
    background: transparent;
    color: var(--text-medium);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--background-cream);
    border-color: var(--text-medium);
    color: var(--text-dark);
}

.btn-danger {
    background: #8B4545;
    border-color: #8B4545;
}

.btn-danger:hover {
    background: #6B2F2F;
    border-color: #6B2F2F;
}

.btn-success {
    background: #556B2F;
    border-color: #556B2F;
}

.btn-success:hover {
    background: #3F4F1F;
    border-color: #3F4F1F;
}

/* ======= Forms ======= */
.form-group {
    display: flex;
    flex-direction: column;
    margin-bottom: 15px;
}

input[type="text"],
input[type="number"],
textarea,
select {
    padding: 8px;
    border: 1px solid #ccc;
    border-radius: 5px;
}

/* ======= Book Grid & Card ======= */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-medium);
}

.empty-state h3 {
    font-family: 'Georgia', serif;
    font-size: 1.8em;
    color: var(--primary-dark);
    margin-bottom: 15px;
    font-weight: normal;
}

.empty-state p {
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 1em;
    color: var(--text-light);
}

.book-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 35px;
    margin-top: 30px;
}

.book-card {
    background: var(--background-light);
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.book-card:hover {
    box-shadow: 0 8px 30px var(--shadow-medium);
    transform: translateY(-5px);
    border-color: var(--accent-gold);
}

.book-image {
    width: 100%;
    height: 350px;
    object-fit: cover;
    background: var(--background-cream);
    border-bottom: 1px solid var(--border-color);
}

.book-image-placeholder {
    width: 100%;
    height: 350px;
    background: linear-gradient(135deg, var(--primary-brown) 0%, var(--primary-dark) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent-gold);
    font-size: 4em;
    border-bottom: 1px solid var(--border-color);
}

.book-card-content {
    padding: 25px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.book-title {
    font-family: 'Georgia', serif;
    font-size: 1.3em;
    color: var(--primary-dark);
    margin-bottom: 10px;
    font-weight: normal;
    line-height: 1.3;
}

.book-author {
    color: var(--text-medium);
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 0.95em;
    margin-bottom: 8px;
    font-style: italic;
}

.book-genre {
    color: var(--text-light);
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 0.85em;
    margin-bottom: 15px;
}

.book-price {
    font-family: 'Georgia', serif;
    font-size: 1.6em;
    color: var(--accent-gold);
    margin: 15px 0;
}

.book-inventory {
    color: var(--text-light);
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 0.9em;
    margin-bottom: 15px;
}

.book-inventory.low {
    color: #8B4545;
    font-weight: 600;
}

.book-card .btn {
    margin-top: auto;
    text-align: center;
}

/* ======= Tables ======= */
.cart-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 30px;
    font-family: 'Segoe UI', Tahoma, sans-serif;
}

.cart-table th {
    background: var(--primary-dark);
    color: var(--background-cream);
    padding: 15px;
    text-align: left;
    font-weight: normal;
    letter-spacing: 0.5px;
    font-size: 0.95em;
}

.cart-table td {
    padding: 18px 15px;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-dark);
}

.cart-table tr:hover {
    background: var(--background-cream);
}

/* ======= Forms ======= */
.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-dark);
    font-weight: 600;
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 0.95em;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    background: var(--background-light);
    font-family: 'Segoe UI', Tahoma, sans-serif;
    font-size: 0.95em;
    color: var(--text-dark);
    transition: all 0.3s ease;
}

.form-group textarea {
    min-height: 120px;
    resize: vertical;
    font-family: 'Georgia', serif;
    line-height: 1.8;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--accent-gold);
    background: var(--background-cream);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
}

.admin-section {
    margin-bottom: 50px;
    padding: 35px;
    background: var(--background-cream);
    border: 1px solid var(--border-color);
}

.admin-section h3 {
    font-family: 'Georgia', serif;
    font-size: 1.8em;
    color: var(--primary-dark);
    margin-bottom: 25px;
    font-weight: normal;
}


/* ======= Responsive Design ======= */
@media (max-width: 1024px) {
    main {
        padding: 40px 30px;
    }
}

@media (max-width: 768px) {
    header {
        padding: 25px 30px;
    }

    header h1 {
        font-size: 2em;
    }

    main {
        padding: 30px 20px;
    }

    .page-title {
        font-size: 2em;
    }

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

    .search-form {
        flex-direction: column;
    }

    .search-form input,
    .search-form select {
        width: 100%;
    }

    .book-grid {
        grid-template-columns: 1fr;
        gap: 25px;
    }

    .cart-table {
        font-size: 0.9em;
    }

    .cart-table th,
    .cart-table td {
        padding: 12px 10px;
    }
}

/* ======= Login + Register ========= */

.auth-container {
    max-width: 480px;
    margin: 60px auto;
    padding: 50px;
    background: var(--background-light);
    border: 1px solid var(--border-color);
    box-shadow: 0 10px 40px var(--shadow-light);
}

.auth-container h2 {
    font-family: 'Georgia', serif;
    font-size: 2em;
    color: var(--primary-dark);
    margin-bottom: 30px;
    font-weight: normal;
    text-align: center;
}

.auth-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.auth-form .btn {
    width: 100%;
    padding: 14px;
    font-size: 1em;
}

.auth-links {
    text-align: center;
    margin-top: 25px;
    font-family: 'Segoe UI', Tahoma, sans-serif;
}

.auth-links a {
    color: var(--accent-gold);
    text-decoration: none;
    border-bottom: 1px solid var(--accent-gold);
}

.auth-links a:hover {
    color: var(--primary-dark);
    border-color: var(--primary-dark);
}

.password-requirements {
    font-size: 0.85em;
    color: var(--text-light);
    font-family: 'Segoe UI', Tahoma, sans-serif;
    line-height: 1.6;
    margin-top: 8px;
}

.error-message {
    color: #8B4545;
    font-size: 0.9em;
    margin-top: 5px;
    font-family: 'Segoe UI', Tahoma, sans-serif;
}

/* ======= Optional: messages ======= */
.success-message { color: green; }
.error-message { color: red; }