/* ============================================================
   xn_theme_modern — 现代样式层
   在 bootstrap-bbs.css 之后加载，通过 CSS 变量 + 更高特异性覆盖核心样式
   不引入 Tailwind/preflight，不动 Bootstrap 基础类
   v1.2 — 配色优化：改善可见度、暗色对比度、导航渐变、变量统一
   ============================================================ */

/* ----------------------------------------------------------
   1. 设计令牌 — 明色
   ---------------------------------------------------------- */
:root {
    --tm-primary: #6366f1;
    --tm-primary-hover: #4338ca;
    --tm-primary-soft: #e0e7ff;
    --tm-bg: #f5f7fa;
    --tm-bg-card: #ffffff;
    --tm-card-hover: #eef2f7;
    --tm-bg-input: #f8f9fb;
    --tm-text: #0f172a;
    --tm-text-2: #4a5568;
    --tm-text-muted: #8896a6;
    --tm-border: #e2e8f0;
    --tm-border-light: #eef1f5;
    --tm-shadow-sm: 0 1px 3px rgba(0,0,0,.06);
    --tm-shadow: 0 2px 6px rgba(0,0,0,.07), 0 1px 2px rgba(0,0,0,.04);
    --tm-shadow-md: 0 8px 24px rgba(0,0,0,.09), 0 2px 6px rgba(0,0,0,.04);
    --tm-radius: .5rem;
    --tm-radius-lg: .75rem;
    --tm-radius-pill: 9999px;
    --tm-transition: 180ms ease;
    --tm-navbar-h: 56px;
    --color-primary: var(--tm-primary);
}

/* ----------------------------------------------------------
   2. 设计令牌 — 暗色
   ---------------------------------------------------------- */
[data-theme="dark"] {
    --tm-primary: #a5b4fc;
    --tm-primary-hover: #818cf8;
    --tm-primary-soft: rgba(165,180,252,.12);
    --tm-bg: #111827;
    --tm-bg-card: #1f2937;
    --tm-card-hover: #374151;
    --tm-bg-input: #1f2937;
    --tm-text: #f1f5f9;
    --tm-text-2: #d1d5db;
    --tm-text-muted: #9ca3af;
    --tm-border: #374151;
    --tm-border-light: #1f2937;
}

/* ----------------------------------------------------------
   3. 全局与布局
   ---------------------------------------------------------- */
body {
    background: var(--tm-bg);
    color: var(--tm-text);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

a {
    color: var(--tm-primary);
    transition: color var(--tm-transition);
}
a:hover {
    color: var(--tm-primary-hover);
}

.text-grey, .text-muted {
    color: var(--tm-text-muted) !important;
}

.break-all {
    word-break: break-word;
}

#body {
    background: var(--tm-bg);
}

/* ----------------------------------------------------------
   4. 顶部导航
   ---------------------------------------------------------- */
#header.navbar {
    background: linear-gradient(135deg, var(--tm-primary) 0%, var(--tm-primary-hover) 100%) !important;
    box-shadow: var(--tm-shadow);
    min-height: var(--tm-navbar-h);
    backdrop-filter: saturate(180%) blur(8px);
}
#header.navbar > .container {
    min-height: var(--tm-navbar-h);
}
[data-theme="dark"] #header.navbar {
    background: var(--tm-bg-card) !important;
    border-bottom: 1px solid var(--tm-border);
}

#header .navbar-brand {
    color: #fff;
    font-weight: 700;
}
#header .navbar-brand:hover {
    color: rgba(255,255,255,.9);
}

#header .navbar-nav .nav-link {
    color: rgba(255,255,255,.8);
    border-radius: var(--tm-radius);
    padding: .5rem .75rem;
    transition: background var(--tm-transition), color var(--tm-transition);
}
#header .navbar-nav .nav-link:hover {
    color: #fff;
    background: rgba(255,255,255,.15);
}
#header .navbar-nav .nav-link.active,
#header .navbar-nav .nav-item.active .nav-link {
    color: #fff;
    background: rgba(255,255,255,.2);
    font-weight: 600;
}

#header .navbar-toggler {
    border-color: rgba(255,255,255,.3);
}
#header .navbar-toggler-icon {
    filter: brightness(2);
}

/* ----------------------------------------------------------
   5. 卡片
   ---------------------------------------------------------- */
.card {
    background: var(--tm-bg-card);
    border: 1px solid var(--tm-border);
    border-radius: var(--tm-radius-lg);
    box-shadow: var(--tm-shadow);
    margin-bottom: 1.25rem;
    transition: box-shadow var(--tm-transition), transform var(--tm-transition);
}
.card > .card-header {
    background: transparent !important;
    background-image: none !important;
    border-bottom: 1px solid var(--tm-border);
    color: var(--tm-text);
    font-size: .9375rem;
    font-weight: 600;
    padding: .875rem 1.25rem;
}
.card > .card-body {
    padding: 1.25rem;
}
.card > .card-footer {
    background: var(--tm-bg);
    border-top: 1px solid var(--tm-border);
    padding: .75rem 1.25rem;
}
.card-title {
    font-weight: 600;
    color: var(--tm-text);
}
[data-theme="dark"] .card {
    border-color: var(--tm-border);
}
.card-threadlist,
.card-thread,
.card-postlist,
.card-site-info,
.card-forum-info,
.card-user-info,
.card-mod-info {
    overflow: hidden;
}

/* ----------------------------------------------------------
   6. 帖子列表
   ---------------------------------------------------------- */
.threadlist {
    list-style: none;
    padding: 0;
    margin: 0;
}
.threadlist > .media,
.threadlist > li.media {
    padding: .875rem 1.25rem;
    border-bottom: 1px solid var(--tm-border-light);
    border-left: 3px solid transparent;
    transition: background var(--tm-transition), border-color var(--tm-transition);
}
.threadlist > .media:hover,
.threadlist > li.media:hover {
    background: var(--tm-card-hover);
    border-left-color: var(--tm-primary);
}
.threadlist > .media:last-child,
.threadlist > li.media:last-child {
    border-bottom: none;
}

.thread .subject {
    font-size: 1rem;
    font-weight: 500;
    color: var(--tm-text);
}
.thread .subject a {
    color: var(--tm-text);
    text-decoration: none;
}
.thread .subject a:hover {
    color: var(--tm-primary);
}

.thread .username,
.thread .username a {
    color: var(--tm-text-2);
    font-size: .8125rem;
}
.thread .date,
.thread .text-muted {
    color: var(--tm-text-muted);
    font-size: .8125rem;
}

.thread .icon {
    color: var(--tm-text-muted);
    margin-right: .25rem;
}
.thread .icon-top-1,
.thread .icon-top-2 {
    color: var(--tm-primary);
}
.thread .icon-lock {
    color: var(--tm-text-muted);
}
.thread .badge {
    font-weight: 500;
    font-size: .75rem;
}

/* ----------------------------------------------------------
   7. 回复列表
   ---------------------------------------------------------- */
.postlist {
    list-style: none;
    padding: 0;
    margin: 0;
}
.postlist > .media,
.postlist > li.media {
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--tm-border-light);
}
.postlist > .media:last-child,
.postlist > li.media:last-child {
    border-bottom: none;
}

.post .username a {
    color: var(--tm-text-2);
    font-weight: 500;
}
.post .date {
    color: var(--tm-text-muted);
    font-size: .8125rem;
}
.post .floor {
    color: var(--tm-text-muted);
    font-size: .75rem;
}

/* ----------------------------------------------------------
   8. 消息内容
   ---------------------------------------------------------- */
.post .message,
.message {
    color: var(--tm-text);
    font-size: .9375rem;
    line-height: 1.75;
}
.post .message img,
.message img {
    border-radius: var(--tm-radius);
    max-width: 100%;
    border: 1px solid var(--tm-border);
}
.post .message blockquote,
.message blockquote {
    border-left: 3px solid var(--tm-primary);
    background: var(--tm-primary-soft);
    padding: .75rem 1rem !important;
    border-radius: 0 var(--tm-radius) var(--tm-radius) 0;
    color: var(--tm-text-2);
    font-size: .875rem;
    background-image: none;
}
.post .message pre,
.message pre {
    background: var(--tm-bg);
    border: 1px solid var(--tm-border);
    border-radius: var(--tm-radius);
    padding: 1rem;
    overflow-x: auto;
    font-size: .8125rem;
}
.post .message code,
.message code {
    background: var(--tm-primary-soft);
    color: var(--tm-primary);
    padding: .125rem .375rem;
    border-radius: .25rem;
    font-size: .8125rem;
}
.post .message pre code,
.message pre code {
    background: transparent;
    color: inherit;
    padding: 0;
}
.post .message a,
.message a {
    color: var(--tm-primary);
}
.media .newpost {
    background: var(--tm-primary);
    color: #fff;
    font-size: .75rem;
    padding: .125rem .5rem;
    border-radius: var(--tm-radius-pill);
}

/* 引用高亮覆盖 */
li.quote {
    background-color: var(--tm-primary-soft);
    background-image: none;
}

/* ----------------------------------------------------------
   9. 头像
   ---------------------------------------------------------- */
.avatar-1,
.avatar-3,
.avatar-4,
.avatar-5 {
    border-radius: var(--tm-radius);
}
.img-circle {
    border-radius: 50%;
}

/* ----------------------------------------------------------
   10. 按钮
   ---------------------------------------------------------- */
.btn {
    border-radius: var(--tm-radius);
    transition: all var(--tm-transition);
    font-weight: 500;
    padding: .5rem 1.25rem;
}
.btn-primary {
    background: var(--tm-primary);
    border-color: var(--tm-primary);
    color: #fff;
}
.btn-primary:hover,
.btn-primary:focus {
    background: var(--tm-primary-hover);
    border-color: var(--tm-primary-hover);
    box-shadow: 0 0 0 .2rem rgba(99,102,241,.25);
}
.btn-secondary {
    background: var(--tm-bg);
    border-color: var(--tm-border);
    color: var(--tm-text);
}
.btn-secondary:hover {
    background: var(--tm-card-hover);
    border-color: var(--tm-text-muted);
}
.btn-danger {
    background: #ef4444;
    border-color: #ef4444;
    color: #fff;
}
.btn-danger:hover {
    background: #dc2626;
    border-color: #dc2626;
}
.btn-link {
    color: var(--tm-primary);
}

/* ----------------------------------------------------------
   11. 表单
   ---------------------------------------------------------- */
.form-control,
.custom-select {
    border-radius: var(--tm-radius);
    border-color: var(--tm-border);
    background: var(--tm-bg-input);
    color: var(--tm-text);
    transition: border-color var(--tm-transition), box-shadow var(--tm-transition);
}
.form-control:focus,
.custom-select:focus {
    border-color: var(--tm-primary);
    box-shadow: 0 0 0 .2rem rgba(99,102,241,.15);
}
[data-theme="dark"] .form-control,
[data-theme="dark"] .custom-select {
    background: var(--tm-bg-input);
    border-color: var(--tm-border);
    color: var(--tm-text);
}
.input-group-text {
    background: var(--tm-bg);
    border-color: var(--tm-border);
    color: var(--tm-text-2);
}

/* ----------------------------------------------------------
   12. 面包屑 / 分页 / 标签
   ---------------------------------------------------------- */
.breadcrumb {
    background: var(--tm-bg-card) !important;
    border: 1px solid var(--tm-border);
    border-radius: var(--tm-radius);
    box-shadow: var(--tm-shadow-sm);
    padding: .625rem 1rem;
}
.breadcrumb:hover {
    background: var(--tm-card-hover) !important;
}
.breadcrumb-item a {
    color: var(--tm-primary);
}
.breadcrumb-item a:hover {
    color: var(--tm-primary-hover);
}
.breadcrumb-item.active {
    color: var(--tm-text-muted);
}

.pagination .page-link {
    border-radius: var(--tm-radius);
    border-color: var(--tm-border);
    color: var(--tm-primary);
    margin: 0 .125rem;
}
.pagination .page-link:hover {
    background: var(--tm-primary-soft);
}
.pagination .page-item.active .page-link {
    background: var(--tm-primary);
    border-color: var(--tm-primary);
    color: #fff;
}
.pagination .page-item.disabled .page-link {
    color: var(--tm-text-muted);
}

.nav-tabs,
.card-header-tabs {
    border-bottom: 1px solid var(--tm-border);
}
.nav-tabs .nav-link,
.card-header-tabs .nav-link {
    color: var(--tm-text-2);
    border-radius: var(--tm-radius) var(--tm-radius) 0 0;
}
.nav-tabs .nav-link:hover,
.card-header-tabs .nav-link:hover {
    border-color: var(--tm-border) var(--tm-border) transparent;
    color: var(--tm-primary);
}
.nav-tabs .nav-link.active,
.card-header-tabs .nav-link.active {
    color: var(--tm-primary);
    border-color: var(--tm-border) var(--tm-border) var(--tm-bg-card);
    background: var(--tm-bg-card) !important;
    background-image: none !important;
    font-weight: 600;
}

/* ----------------------------------------------------------
   13. 下拉菜单
   ---------------------------------------------------------- */
.dropdown-menu {
    border-radius: var(--tm-radius);
    border-color: var(--tm-border);
    box-shadow: var(--tm-shadow-md);
    padding: .375rem 0;
}
.dropdown-item {
    color: var(--tm-text);
    padding: .5rem 1.25rem;
    transition: background var(--tm-transition), color var(--tm-transition);
}
.dropdown-item:hover,
.dropdown-item:focus {
    background: var(--tm-primary-soft);
    color: var(--tm-primary);
}

/* ----------------------------------------------------------
   14. 列表组 / 模态
   ---------------------------------------------------------- */
.list-group-item {
    border-color: var(--tm-border-light);
    padding: .75rem 1.25rem;
}
.modal-content {
    border-radius: var(--tm-radius-lg);
    border: none;
    box-shadow: var(--tm-shadow-md);
}
.modal-header {
    border-bottom: 1px solid var(--tm-border);
}
.modal-footer {
    border-top: 1px solid var(--tm-border);
}

/* ----------------------------------------------------------
   15. 侧栏
   ---------------------------------------------------------- */
.aside .btn-block {
    border-radius: var(--tm-radius);
}

/* ----------------------------------------------------------
   16. 底部
   ---------------------------------------------------------- */
#footer {
    background: var(--tm-bg-card) !important;
    border-top: 1px solid var(--tm-border);
    color: var(--tm-text-2) !important;
    padding: 1.5rem 0;
}
[data-theme="dark"] #footer {
    background: var(--tm-bg-card) !important;
}
#footer a {
    color: var(--tm-text-muted);
}
#footer a:hover {
    color: var(--tm-primary);
}

/* ----------------------------------------------------------
   17. 暗色 Bootstrap 硬编码色补丁
   ---------------------------------------------------------- */
[data-theme="dark"] .bg-light {
    background: var(--tm-bg-card) !important;
}
[data-theme="dark"] .bg-white {
    background: var(--tm-bg-card) !important;
}
[data-theme="dark"] .text-dark {
    color: var(--tm-text) !important;
}
[data-theme="dark"] hr {
    border-color: var(--tm-border);
}
[data-theme="dark"] .table {
    color: var(--tm-text);
}
[data-theme="dark"] .table td,
[data-theme="dark"] .table th {
    border-color: var(--tm-border);
}
[data-theme="dark"] .card-header-tabs .nav-link.active {
    background: var(--tm-bg-card);
    color: var(--tm-primary);
    background-image: none;
}

/* ----------------------------------------------------------
   18. 暗色切换按钮
   ---------------------------------------------------------- */
.xn-theme-toggle {
    position: fixed;
    bottom: 1.5rem;
    right: 1.5rem;
    z-index: 1050;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--tm-bg-card);
    border: 1px solid var(--tm-border);
    box-shadow: var(--tm-shadow);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--tm-transition);
    padding: 0;
}
.xn-theme-toggle:hover {
    box-shadow: var(--tm-shadow-md);
    border-color: var(--tm-primary);
}
.xn-theme-toggle svg {
    width: 20px;
    height: 20px;
    fill: none;
    stroke: var(--tm-text-2);
}
.xn-theme-toggle .icon-sun {
    display: none;
}
[data-theme="dark"] .xn-theme-toggle .icon-sun {
    display: block;
}
[data-theme="dark"] .xn-theme-toggle .icon-moon {
    display: none;
}

/* ----------------------------------------------------------
   19. 响应式
   ---------------------------------------------------------- */
@media (max-width: 991.98px) {
    .xn-theme-toggle {
        bottom: 1rem;
        right: 1rem;
        width: 40px;
        height: 40px;
    }
    .threadlist > .media,
    .postlist > .media {
        padding: .75rem;
    }
}

/* ----------------------------------------------------------
   20. 滚动条
   ---------------------------------------------------------- */
::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: var(--tm-bg);
}
::-webkit-scrollbar-thumb {
    background: var(--tm-border);
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: var(--tm-text-muted);
}

/* ----------------------------------------------------------
   21. 选区
   ---------------------------------------------------------- */
::selection {
    background: var(--tm-primary);
    color: #fff;
}