body {
    font-family: 'Inter', sans-serif;
    background-color: #f5f7fa;
}

.navbar {
    height: 64px;
    box-shadow: 0 1px 0 rgba(0, 0, 0, .06);
}

/* Remove default Bootstrap caret */
.nav-link.dropdown-toggle::after {
    display: none;
}

/* Custom arrow */
.user-caret {
    font-size: 12px;
    color: #6c757d;
    margin-left: 6px;
}

.search-box {
    max-width: 720px;
    margin: auto;
}

/* ---------- CATEGORY SIDEBAR ---------- */
.category-sidebar {
    background: #ffffff;
    border-radius: 12px;
    padding: 16px;
    box-shadow: 0 1px 2px rgba(0, 0, 0, .04);
    position: sticky;
    top: 90px;
}

.category-sidebar h6 {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 12px;
}

.category-list,
.sub-category {
    list-style: none;
    padding: 0;
    margin: 0;
}

.category-list>li {
    margin-bottom: 10px;
}

.category-list a {
    font-size: 14px;
    font-weight: 500;
    color: #1f2937;
    text-decoration: none;
}

.category-list a:hover {
    color: #0d6efd;
}

.sub-category {
    padding-left: 14px;
    margin-top: 6px;
}

.sub-category a {
    font-size: 13px;
    font-weight: 400;
    color: #6b7280;
}

/* ---------- BOOK TILE ---------- */
.book-tile {
    cursor: pointer;
    transition: transform .25s ease;
}

.book-tile:hover {
    transform: translateY(-6px);
}

.book-cover-wrap {
    position: relative;
    aspect-ratio: 2 / 3;
    border-radius: 16px;
    overflow: hidden;
    background: #e5e7eb;
    box-shadow:
        0 10px 25px rgba(0, 0, 0, .12),
        0 2px 6px rgba(0, 0, 0, .08);
}

.book-cover-wrap img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform .4s ease;
}

.book-tile:hover img {
    transform: scale(1.05);
}

.book-badge {
    position: absolute;
    top: 12px;
    left: 12px;
    background: rgba(255, 255, 255, .95);
    color: #166534;
    font-size: 12px;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: 999px;
    z-index: 2;
}

/* ---------- OVERLAY ---------- */
.book-overlay {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    padding: 22px 16px 20px;

    background: linear-gradient(to top,
            rgba(0, 0, 0, .92),
            rgba(0, 0, 0, .65),
            rgba(0, 0, 0, .25),
            transparent);

    color: #fff;
}

.overlay-title {
    font-size: 15px;
    font-weight: 600;
    line-height: 1.35;
    margin-bottom: 4px;

    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.overlay-author {
    font-size: 13px;
    opacity: .9;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* ---------- FOOTER ---------- */
footer {
    background: #0f172a;
    color: #cbd5e1;
}

footer h6 {
    font-size: 14px;
    font-weight: 600;
    color: #f8fafc;
    margin-bottom: 12px;
}

footer a {
    color: #94a3b8;
    text-decoration: none;
    font-size: 14px;
}

footer a:hover {
    color: #e2e8f0;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, .08);
    margin-top: 24px;
    padding-top: 16px;
    font-size: 13px;
    color: #94a3b8;
}