/* ================================================= */
/* 1. KHAI BÁO BIẾN VÀ CƠ SỞ */
/* ================================================= */

:root {
    /* Màu sắc đặc trưng theo mẫu */
    --custom-blue: #004c97;      /* Màu xanh đậm của logo */
    --custom-green: #009245;     /* Màu xanh lá cây của menu Active */
    --custom-dark-green: #00773b; /* Màu xanh lá cây đậm của thanh tìm kiếm và Footer */
    --custom-pink: #f7a6a4;      /* Màu hồng của banner */
    --custom-text-color: #333;
}

body {
    font-family: Arial, sans-serif;
    color: var(--custom-text-color);
}

/* Các lớp màu dùng xuyên suốt */
.custom-blue-text {
    color: var(--custom-blue) !important;
}

.custom-green-bg {
    background-color: var(--custom-green) !important;
}

.custom-dark-green-bg {
    background-color: var(--custom-dark-green) !important;
}

.custom-green-text {
    color: var(--custom-green) !important;
    font-weight: bold;
}

/* ================================================= */
/* 2. HEADER & NAVBAR */
/* ================================================= */

/* Định dạng tiêu đề logo */
.small-title {
    font-size: 0.75rem; 
}

.large-title {
    font-size: 1.25rem; 
    line-height: 1;
}

/* Định dạng liên kết menu */
.nav-link {
    color: var(--custom-text-color) !important;
    padding: 0.5rem 1rem;
    transition: color 0.3s;
}

.nav-link:hover {
    color: var(--custom-green) !important;
}

/* Nút/Mục đang Active */
.nav-link.active.custom-green-bg {
    padding: 0.375rem 0.75rem !important; 
    color: white !important;
}

/* Thanh tìm kiếm dưới Navbar */
.search-bar-wrapper .search-box input {
    width: 300px;
}

.search-bar-wrapper .btn-outline-light {
    border-color: white !important;
}


/* ================================================= */
/* 3. BANNER (Chỉ Trang Chủ) */
/* ================================================= */

.custom-carousel-height {
    height: 350px; 
}

.custom-pink-bg {
    background-color: var(--custom-pink);
    display: flex;
    align-items: center;
    justify-content: center;
}

.custom-welcome-text {
    font-size: 3rem;
    text-shadow: 2px 2px #fff, -2px -2px var(--custom-blue);
    position: absolute; 
    left: 10%;
    top: 50%;
    transform: translateY(-50%);
}

.custom-year {
    font-weight: bold;
    font-size: 1.5rem !important;
}


/* ================================================= */
/* 4. NỘI DUNG CHÍNH (Trang Chủ) */
/* ================================================= */

.custom-search-section-border-color {
    border: 3px solid var(--custom-dark-green) !important;
}

.custom-nav-tabs .nav-link {
    background-color: #f8f9fa; 
    border: 1px solid #ccc;
    border-bottom: none;
    border-radius: 0;
    margin-right: 5px;
    color: var(--custom-text-color);
}

.custom-nav-tabs .nav-link.active {
    background-color: #fff; 
    border-top: 3px solid var(--custom-green); 
    color: var(--custom-green);
    font-weight: bold;
}

.btn.custom-green-bg {
    background-color: var(--custom-dark-green) !important;
}

.book-cover {
    transition: transform 0.3s;
    box-shadow: 2px 2px 5px rgba(0, 0, 0, 0.2);
}

.book-cover:hover {
    transform: translateY(-5px); 
}

/* ================================================= */
/* 5. TRANG HỆ THỐNG THƯ VIỆN & GIỚI THIỆU */
/* ================================================= */

.custom-library-card {
    transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
    border: 1px solid #ddd;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1); 
}

.custom-library-card:hover {
    transform: translateY(-5px); 
    border-color: var(--custom-green); 
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.custom-library-card .card-img-top {
    height: 150px; 
    object-fit: cover;
}

/* ================================================= */
/* 6. TRANG NỘI QUY */
/* ================================================= */

.custom-rule-card {
    border-radius: 10px;
    overflow: hidden; 
    border: 1px solid #ddd;
}

.custom-rule-header {
    font-size: 1.1rem;
    padding: 1rem 1.25rem;
}

.custom-borrow-header {
    background-color: #f0f8ff !important; 
    color: var(--custom-blue) !important;
    border-bottom: 3px solid var(--custom-blue);
}

.rule-list .list-group-item {
    border-left: 3px solid transparent;
    transition: background-color 0.3s, border-left 0.3s;
}

.rule-list .list-group-item:hover {
    background-color: #f7fff7; 
    border-left-color: var(--custom-green);
}

.rule-danger {
    background-color: #fff8f8; 
    color: #cc0000; 
}

.rule-danger:hover {
    background-color: #ffeaea;
    border-left-color: #cc0000;
}

/* ================================================= */
/* 7. TRANG FAQs */
/* ================================================= */

.custom-accordion-faq .accordion-item {
    border: 1px solid #ddd;
    border-radius: 8px !important;
    overflow: hidden;
    transition: box-shadow 0.3s;
}

.custom-accordion-faq .accordion-item:hover {
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.custom-accordion-button {
    background-color: #f7fff7 !important; 
    color: var(--custom-blue) !important; 
    font-weight: bold;
    font-size: 1.05rem;
    padding: 1rem 1.25rem;
    border: none;
    transition: background-color 0.3s;
}

.custom-accordion-button:not(.collapsed) {
    background-color: var(--custom-green) !important; 
    color: white !important;
}

.accordion-button:not(.collapsed)::after {
    filter: brightness(0) invert(1); 
}

/* ================================================= */
/* 8. FOOTER VÀ NÚT NỔI */
/* ================================================= */

.custom-footer-heading {
    text-transform: uppercase;
    font-size: 1rem;
    padding-bottom: 5px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.3); 
}

.footer-links a {
    color: white;
    text-decoration: none;
    display: block;
    padding: 5px 0;
    transition: color 0.3s, padding-left 0.3s;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-links a:hover {
    color: #ffd700; 
    padding-left: 5px; 
}

.custom-access-box-border {
    border: 2px solid rgba(255, 255, 255, 0.7) !important;
}

.custom-counter-number {
    letter-spacing: 5px; 
    font-family: monospace; 
    color: #ffd700; 
}

.custom-horizontal-line {
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    opacity: 1; 
}

.social-icon-box {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    width: 35px;
    height: 35px;
    border-radius: 5px;
    color: white;
    font-size: 1.2rem;
    margin-right: 8px;
    text-decoration: none;
    transition: opacity 0.3s;
}

.custom-facebook-bg { background-color: #3b5998; }
.custom-youtube-bg { background-color: #ff0000; }
.custom-tiktok-bg { background-color: #000000; }
.custom-zalo-bg { 
    background-color: #0080ff; 
    padding: 5px;
}

.scroll-to-top-btn {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 45px;
    height: 45px;
    /* ... (CSS còn lại) ... */
}

.floating-zalo-btn {
    position: fixed;
    bottom: 20px;
    right: 70px;
    width: 45px;
    height: 45px;
    /* ... (CSS còn lại) ... */
}