.container {margin-bottom: .5rem;}

.knowledge-center {
    padding: 60px 0;
    background-color: #222533;
    min-height: 80vh;
}

.page-header {
    text-align: center;
    margin-bottom: 40px;
}
.page-title {
    color: #FFFFFF;
    font-size: 0.25rem;
    font-weight: 600;
    margin-bottom: 15px;
}
.page-description {
    color: #CCCCCC;
    font-size: 0.25rem;
    max-width: 600px;
    margin: 0 auto;
}

.breadcrumb-nav {
    background: transparent;
    padding: 0;
    margin-bottom: 30px;
}
.breadcrumb-nav .breadcrumb {
    background: rgba(255,255,255,0.1);
    border-radius: 8px;
    padding: 12px 20px;
}
.breadcrumb-nav .breadcrumb > li + li:before {
    content: "/";
    color: #00A2FF;
}
.breadcrumb-nav .breadcrumb a {
    color: #00A2FF;
    text-decoration: none;
}
.breadcrumb-nav .breadcrumb .active {
    color: #FFFFFF;
}

.search-filter-area {
    background: rgba(255,255,255,0.05);
    border-radius: 12px;
    padding: 25px;
    margin-bottom: 40px;
}
.search-input-group {
    position: relative;
    margin-bottom: 20px;
}
.search-input {
    width: 100%;
    padding: 15px 50px 15px 20px;
    border: 2px solid #404556;
    border-radius: 8px;
    background: #2a2e3f;
    color: #FFFFFF;
    font-size: 16px;
}
.search-input:focus {
    border-color: #00A2FF;
    outline: none;
}
.search-btn {
    position: absolute;
    right: 10px;
    top: 50%;
    transform: translateY(-50%);
    background: #00A2FF;
    border: none;
    padding: 8px 12px;
    border-radius: 6px;
    color: white;
    cursor: pointer;
}

.filter-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 20px;
}


.filter-tag {
    padding: 8px 15px;
    background: #33384a;
    border: 1px solid #404556;
    border-radius: 20px;
    color: #E0E0E0;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 14px;
}
.filter-tag a{
    color: #E0E0E0;
}

.filter-tag:hover, .filter-tag.active{
    background: #00A2FF;
    border-color: #00A2FF;
    color: #FFFFFF;
}
.filter-tag a:hover{
    color: #FFFFFF;
}
.filter-tag a{
    text-decoration: none;
}

.sort-options {
    display: flex;
    align-items: center;
    gap: 15px;
}
.sort-label {
    color: #CCCCCC;
    font-weight: 500;
}
.sort-select {
    padding: 8px 12px;
    background: #2a2e3f;
    border: 1px solid #404556;
    border-radius: 6px;
    color: #FFFFFF;
}

.content-layout {
    display: flex;
    gap: 25px;
}

.sidebar-nav {
    flex: 0 0 200px;
    background: rgba(255,255,255,0.05);
    border-radius: 12px;
    padding: 20px;
    height: fit-content;
    position: sticky;
    top: 20px;
}
.nav-title {
    color: #FFFFFF;
    font-size: 0.2rem;
    font-weight: 600;
    margin-bottom: 20px;
    border-bottom: 2px solid #00A2FF;
    padding-bottom: 10px;
    text-align: center;
}
.nav-tree {
    list-style: none;
    padding: 0;
    margin: 0;
    text-align: center;
}
.nav-tree li {
    margin-bottom: 8px;
}
.nav-tree a {
    color: #CCCCCC;
    text-decoration: none;
    padding: 8px 0;
    display: block;
    transition: color 0.3s ease;
}
.nav-tree a:hover, .nav-tree a.active {
    color: #00A2FF;
}

.main-content {
    flex: 1;
}

.knowledge-grid {
    display: grid;
    gap: 20px;
}
.knowledge-item {
    background: rgba(255,255,255,0.05);
    border: 1px solid #404556;
    border-radius: 12px;
    padding: 25px;
    transition: all 0.3s ease;
}
.knowledge-item:hover {
    border-color: #00A2FF;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0, 162, 255, 0.1);
}
.item-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 15px;
}
.item-title {
    color: #FFFFFF;
    font-size: 0.2rem;
    font-weight: 600;
    margin: 0;
    line-height: 1.4;
}
.item-category {
    background: #00A2FF;
    color: #FFFFFF;
    padding: 4px 10px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
}
.item-summary {
    color: #CCCCCC;
    line-height: 1.6;
    margin-bottom: 15px;
}
.item-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 14px;
    color: #999999;
}
.item-date {
    display: flex;
    align-items: center;
    gap: 5px;
}
.item-stats {
    display: flex;
    gap: 15px;
}
.read-more-btn {
    background: #00A2FF;
    color: #FFFFFF;
    border: none;
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    transition: all 0.3s ease;
}
.read-more-btn:hover {
    background: #0099ff;
    transform: translateY(-1px);
}

.pagination-wrapper {
    margin-top: 40px;
    text-align: center;
}
.pagination {
    display: inline-flex;
    background: rgba(255,255,255,0.05);
    border-radius: 8px;
    overflow: hidden;
}
.pagination a, .pagination span {
    padding: 12px 16px;
    color: #CCCCCC;
    text-decoration: none;
    border-right: 1px solid #404556;
    transition: all 0.3s ease;
}
.pagination a:hover, .pagination .current {
    background: #00A2FF;
    color: #FFFFFF;
}
.pagination a:last-child, .pagination span:last-child {
    border-right: none;
}

@media (max-width: 1024px) {
    .page-title { font-size: 1.35rem; }
    .content-layout { flex-direction: column; }
    .sidebar-nav { flex: none; }
}
@media (max-width: 768px) {
    .page-title { font-size: 1.25rem; }
    .search-filter-area { padding: 20px; }
    .knowledge-item { padding: 20px; }
    .filter-tags { gap: 8px; }
    .sort-options { flex-direction: column; align-items: flex-start; }
}
@media (max-width: 480px) {
    .page-title { font-size: 1.1rem; }
    .page-description { font-size: 0.8rem; }
    .nav-title { font-size: 0.9rem; }
    .item-title { font-size: 0.9rem; }
    .knowledge-center { padding: 40px 0; }
    .search-filter-area { padding: 15px; }
    .filter-tags { flex-direction: column; }
}
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
.page-header {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-bottom: 24px;
    text-align: center;
}

.page-title {
    margin: 0;
    color: #E8F2FF;
    font-weight: 700;
    line-height: 1.25;
    letter-spacing: 0.2px;
    /* 视口自适应，不会“拉伸变形”，只是等比缩放字号 */
    font-size: clamp(22px, 3.0vw, 34px);
    max-width: 90ch;         /* 限制行宽以保证排版稳定 */
    transform: none;         /* 禁止任何缩放/变形 */
}

.page-description {
    margin: 0;
    color: #AEB4C0;
    line-height: 1.7;
    font-size: clamp(13.5px, 1.6vw, 16px);
    max-width: 72ch;         /* 较短的理想阅读宽度 */
    opacity: 0.95;
    /* 让换行更均匀/自然，不出现拉伸或溢出 */
    text-wrap: balance;
    word-break: normal;
    overflow-wrap: break-word;
    hyphens: auto;
    -webkit-hyphens: auto;
    transform: none;         /* 禁止变形 */
}

/* 适配大屏：略增字重感，保持居中 */
@media (min-width: 1440px) {
    .page-title { font-size: clamp(24px, 2.2vw, 36px); }
}

/* 适配平板与手机：留白更紧凑，继续居中 */
@media (max-width: 1024px) {
    .page-header { margin-bottom: 20px; }
}
@media (max-width: 768px) {
    .page-title { font-size: clamp(20px, 4.6vw, 26px); }
    .page-description { font-size: clamp(13px, 3.8vw, 14.5px); max-width: 92%; }
}
@media (max-width: 480px) {
    .page-header { gap: 6px; margin-bottom: 16px; }
    .page-title { letter-spacing: 0.1px; }
}