/* ===== PDF查看器样式 ===== */

.pdf-module {
    background: var(--surface-strong);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    margin: 20px 0;
    overflow: hidden;
}

.pdf-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    background: linear-gradient(135deg, var(--primary), var(--primary-2));
    color: white;
}

.pdf-header h2 {
    margin: 0;
    font-size: 1.5em;
    font-weight: 600;
}

.pdf-controls {
    display: flex;
    align-items: center;
    gap: 12px;
}

.pdf-controls .btn {
    background: rgba(255, 255, 255, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: white;
    padding: 8px 12px;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
}

.pdf-controls .btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-1px);
}

.pdf-controls .btn.active {
    background: rgba(255, 255, 255, 0.4);
}

.page-info {
    font-size: 0.9em;
    margin: 0 10px;
}

#pdfPageInput {
    width: 60px;
    text-align: center;
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid rgba(255, 255, 255, 0.5);
    border-radius: 4px;
    padding: 4px;
    color: var(--text);
}

.pdf-content {
    position: relative;
    transition: all 0.3s ease;
}

.pdf-content.fullscreen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 1000;
    background: white;
}

#pdfObject {
    width: 100%;
    min-height: 600px;
    border: none;
}

.pdfjs-viewer {
    width: 100%;
    min-height: 600px;
    background: white;
    overflow: auto;
    -webkit-overflow-scrolling: touch;
    display: flex;
    align-items: flex-start;
    justify-content: center;
    padding: 16px;
    box-sizing: border-box;
}

#pdfJsCanvas {
    max-width: 100%;
    height: auto;
}

.pdf-fallback {
    padding: 40px;
    text-align: center;
    color: var(--text-muted);
}

.pdf-fallback a {
    color: var(--primary);
    text-decoration: none;
}

.pdf-fallback a:hover {
    text-decoration: underline;
}

/* 目录下拉菜单 */
.pdf-toc-dropdown {
    position: relative;
    display: inline-flex;
}

.pdf-toc-menu {
    position: fixed;
    left: 0;
    top: 0;
    width: 380px;
    max-width: min(380px, calc(100vw - 24px));
    max-height: 0;
    overflow: hidden;
    background: var(--surface-strong);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    z-index: 1002;
    transform-origin: top right;
    opacity: 0;
    transform: translateY(-8px) scale(0.98);
    pointer-events: none;
    transition: max-height 300ms ease, opacity 300ms ease, transform 300ms ease;
    -webkit-overflow-scrolling: touch;
}

.pdf-toc-menu .page-num {
    display: none;
}

.pdf-toc-menu.open {
    max-height: var(--pdf-toc-max-height, 70vh);
    overflow: auto;
    opacity: 1;
    transform: translateY(0) scale(1);
    pointer-events: auto;
}

.pdf-toc-menu {
    scrollbar-width: thin;
    scrollbar-color: var(--primary) transparent;
}

.pdf-toc-menu::-webkit-scrollbar {
    width: 10px;
}

.pdf-toc-menu::-webkit-scrollbar-track {
    background: transparent;
}

.pdf-toc-menu::-webkit-scrollbar-thumb {
    background-color: var(--primary);
    border-radius: 999px;
    border: 2px solid transparent;
    background-clip: content-box;
}

.pdf-toc-menu::-webkit-scrollbar-thumb:hover {
    background-color: var(--primary-2);
}

@media (prefers-reduced-motion: reduce) {
    .pdf-toc-menu {
        transition: none;
    }
}

@media (max-width: 768px) {
    .pdf-toc-menu {
        width: min(420px, calc(100vw - 24px));
    }
}

.pdf-dropdown-list {
    list-style: none;
    margin: 0;
    padding: 20px;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
}

.pdf-dropdown-heading {
    grid-column: 1 / -1;
    color: var(--primary);
    font-size: 1.05em;
    font-weight: 600;
    border-bottom: 2px solid var(--primary);
    padding: 4px 0 8px 0;
    margin: 6px 0 2px 0;
}

.pdf-dropdown-separator {
    grid-column: 1 / -1;
    height: 1px;
    background: var(--border);
    opacity: 0.8;
    margin: 6px 0;
}

.pdf-dropdown-item.has-submenu {
    grid-column: 1 / -1;
}

.pdf-dropdown-btn {
    width: 100%;
    text-align: left;
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: var(--surface-muted);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
    border: 1px solid var(--border);
    color: inherit;
}

.pdf-dropdown-btn:hover {
    background: var(--surface);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.pdf-dropdown-btn:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

.pdf-dropdown-btn i {
    color: var(--primary);
    width: 16px;
    text-align: center;
    flex: 0 0 auto;
}

.pdf-dropdown-label {
    flex: 1 1 auto;
    font-weight: 500;
}

.pdf-dropdown-btn.is-active {
    background: var(--surface);
    border-color: var(--primary);
}

.pdf-dropdown-btn.is-selected {
    border-color: var(--primary);
    box-shadow: inset 0 0 0 1px var(--primary), var(--shadow-sm);
}

.pdf-dropdown-btn[disabled],
.pdf-dropdown-btn[aria-disabled="true"] {
    opacity: 0.45;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.pdf-dropdown-item.has-submenu > .pdf-dropdown-btn::after {
    content: "›";
    color: var(--text-muted);
    font-weight: 700;
    margin-left: 8px;
}

.pdf-dropdown-submenu {
    list-style: none;
    margin: 6px 0 0 0;
    padding: 0 0 0 18px;
    display: none;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
}

.pdf-dropdown-item.submenu-open > .pdf-dropdown-submenu {
    display: grid;
}

@media (max-width: 768px) {
    .pdf-dropdown-list {
        grid-template-columns: 1fr;
    }

    .pdf-dropdown-submenu {
        grid-template-columns: 1fr;
    }
}

.toc-loading {
    text-align: center;
    color: var(--text-muted);
    padding: 40px 0;
}

.toc-section {
    margin-bottom: 30px;
}

.toc-section h4 {
    margin: 0 0 16px 0;
    color: var(--primary);
    font-size: 1.1em;
    border-bottom: 2px solid var(--primary);
    padding-bottom: 8px;
}

.toc-items {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.toc-item {
    display: flex;
    align-items: center;
    padding: 12px 16px;
    background: var(--surface-muted);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
    border: 1px solid var(--border);
}

.toc-item:hover {
    background: var(--surface);
    transform: translateX(4px);
    box-shadow: var(--shadow-sm);
}

.toc-item i {
    margin-right: 12px;
    color: var(--primary);
    width: 16px;
    text-align: center;
}

.toc-item span:first-of-type {
    flex: 1;
    font-weight: 500;
}

.page-num {
    background: var(--primary);
    color: white;
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 0.8em;
    font-weight: 600;
}

/* 移动端适配 */
@media (max-width: 768px) {
    .pdf-header {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
    
    .pdf-controls {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    #pdfObject {
        min-height: 400px;
    }
    
    .page-info {
        order: -1;
        width: 100%;
        text-align: center;
        margin-bottom: 10px;
    }
}

/* 暗色模式支持 */
@media (prefers-color-scheme: dark) {
    .pdf-module {
        background: #2d3748;
    }
    
    .toc-item {
        background: #4a5568;
        border-color: #4a5568;
    }
    
    .toc-item:hover {
        background: #4a5568;
    }
}