/**
 * Document Center — Minimal Style
 * Chỉ hiển thị: ảnh bìa + tên document
 * Responsive: 3 cột desktop, 2 cột tablet, 2 cột mobile
 */

/* ========================================
   Variables
   ======================================== */
:root {
    --dc-primary: #1a2b3c;
    --dc-text: #333333;
    --dc-text-light: #888888;
    --dc-border: #e0e0e0;
    --dc-container: 1100px;
}

/* ========================================
   Container
   ======================================== */
.dcenter-container {
    width: 100%;
    max-width: var(--dc-container);
    margin: 0 auto;
    padding: 0 1.25rem;
}

@media (min-width: 768px) {
    .dcenter-container {
        padding: 0 2.5rem;
    }
}

/* ========================================
   Hero
   ======================================== */
.dcenter-hero {
    padding: 2.5rem 0 2rem;
}

.dcenter-breadcrumb {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 0.8125rem;
    color: #aaa;
    margin-bottom: 1.25rem;
}

.dcenter-breadcrumb a {
    color: #aaa;
    text-decoration: none;
}

.dcenter-breadcrumb a:hover {
    color: var(--dc-text);
}

.dcenter-hero__title {
    font-size: 1.125rem;
    font-weight: 400;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--dc-text-light);
    text-align: center;
    margin: 0 0 1rem;
}

.dcenter-hero__divider {
    width: 40px;
    height: 2px;
    background: var(--dc-text);
    margin: 0 auto;
}

/* ========================================
   Body
   ======================================== */
.dcenter-body {
    padding: 2rem 0 4rem;
}

/* ========================================
   Section
   ======================================== */
.dcenter-section {
    margin-bottom: 1rem;
}

.dcenter-section__label {
    font-size: 0.8125rem;
    font-weight: 500;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--dc-text-light);
    text-align: center;
    margin: 0 0 2rem;
}

/* Divider giữa các section */
.dcenter-divider {
    border: none;
    border-top: 1px solid var(--dc-border);
    max-width: 100%;
    margin: 2.5rem 0 2.5rem;
}

/* ========================================
   Grid
   ======================================== */
.dcenter-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem 1.5rem;
}

@media (min-width: 640px) {
    .dcenter-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 2.5rem 2rem;
    }
}

@media (min-width: 1024px) {
    .dcenter-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 3rem 2.5rem;
    }
}

/* ========================================
   Document Item
   ======================================== */
.dcenter-item {
    display: block;
    text-align: center;
    text-decoration: none;
    color: inherit;
}

/* Ảnh bìa */
.dcenter-item__cover {
    aspect-ratio: 210 / 297;  /* tỷ lệ A4 */
    overflow: hidden;
    border-radius: 2px;
    margin-bottom: 0.875rem;
    box-shadow:
        0 1px 4px rgba(0, 0, 0, 0.06),
        0 0 0 0.5px rgba(0, 0, 0, 0.08);
    transition: box-shadow 0.3s ease, transform 0.3s ease;
    background: #f5f5f5;
}

.dcenter-item:hover .dcenter-item__cover {
    box-shadow:
        0 8px 24px rgba(0, 0, 0, 0.1),
        0 0 0 0.5px rgba(0, 0, 0, 0.08);
    transform: translateY(-3px);
}

.dcenter-item__img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.dcenter-item__placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #ccc;
}

/* Tên document */
.dcenter-item__title {
    font-size: 0.8125rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    line-height: 1.45;
    color: var(--dc-text);
    margin: 0 0 0.125rem;
}

.dcenter-item:hover .dcenter-item__title {
    color: var(--dc-primary);
}

/* Subtitle (tuỳ chọn — excerpt) */
.dcenter-item__sub {
    font-size: 0.75rem;
    color: var(--dc-text-light);
    letter-spacing: 0.02em;
    text-transform: uppercase;
    line-height: 1.4;
    margin: 0;
}

/* ========================================
   Empty State
   ======================================== */
.dcenter-empty {
    text-align: center;
    padding: 4rem 2rem;
    color: var(--dc-text-light);
    font-size: 0.875rem;
}

/* ========================================
   Accessibility
   ======================================== */
@media (prefers-reduced-motion: reduce) {
    .dcenter-item__cover {
        transition: none;
    }
    .dcenter-item:hover .dcenter-item__cover {
        transform: none;
    }
}

.dcenter-item:focus-visible {
    outline: 2px solid var(--dc-primary);
    outline-offset: 4px;
    border-radius: 2px;
}