/* ============================================================
   SCITOP-LITE · 研途导航精简主题
   ============================================================ */

:root {
    --bg: #fff;
    --accent-color: #708d81;
    --accent-color-darker: color-mix(in srgb, var(--accent-color) 70%, rgba(0, 0, 0));
    --accent-color-light: color-mix(in srgb, var(--accent-color) 35%, #fff);
    --accent-color-faint: color-mix(in srgb, var(--accent-color) 12%, #fff);

    /* 文字色阶 */
    --text-strong: #262626;   /* neutral-800 */
    --text-title: #171717;    /* neutral-900 */
    --text-body: #404040;     /* neutral-700 */
    --text-muted: #737373;    /* mist-500 */
    --text-faint: #a3a3a3;    /* mist-400 */
    --text-fainter: #d4d4d4;  /* mist-300 */

    --border-color: #e7e7e7;
    --hover-bg: #eff2f0;      /* 悬停指示器背景（浅灰绿） */

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-full: 999px;

    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", Helvetica, Arial, sans-serif;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    overflow-x: hidden;
}

body {
    overflow-x: hidden;
    font-family: var(--font-sans);
    background: var(--bg);
    color: var(--text-body);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

a {
    color: inherit;
    text-decoration: none;
}

img {
    display: block;
    max-width: 100%;
}

/* ============================================================
   布局容器：网站列表区自适应加宽，头部等保持原阅读宽度
   ============================================================ */
.container {
    max-width: 62rem;
    margin: 0 auto;
    padding: 3.5rem 1.25rem 4.5rem;
    display: flex;
    flex-direction: column;
    gap: 2.5rem;
}

/* 顶部模块与网站列表同宽（62rem）；页脚保持原单栏宽度 */
.site-header,
.site-footer {
    width: 100%;
    max-width: 62rem;
    margin-inline: auto;
}

@media (max-width: 640px) {
    .container {
        padding-top: 2rem;
        gap: 2rem;
    }
}

/* ============================================================
   站点头部：sticky 圆形头像（视差）+ 站名 + slogan
   ============================================================ */
.site-header {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 1.25rem;
}

/* 顶部右侧内容：站名行 + 搜索 + 分类导航，紧凑纵向排布 */
.header-main {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 0.625rem;
}

.header-titlebar {
    display: flex;
    align-items: baseline;
    flex-wrap: wrap;
    column-gap: 0.75rem;
}

.header-titlebar .site-yiyan {
    margin-left: auto;
    margin-top: 0;
    font-size: 0.75rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 55%;
}

/* sticky 头像按钮（视差） */
.sticky-back-btn-wrapper {
    position: sticky;
    top: 1.25rem;
    z-index: 20;
    width: 56px;
    height: 56px;
    align-self: flex-start;
}

.sticky-back-btn-container {
    width: 100%;
    height: 100%;
}

.parallax {
    width: 100%;
    height: 100%;
    flex-shrink: 0;
}

.parallax-inner {
    width: 100%;
    height: 100%;
    will-change: transform;
    transition: transform .3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.sticky-back-button {
    display: block;
    width: 100%;
    height: 100%;
}

.avatar-circle {
    position: relative;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    overflow: hidden;
    background: var(--accent-color-faint);
    box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.04);
}

.avatar-img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 50%;
    user-select: none;
    transition: transform .3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.avatar-circle:hover .avatar-img {
    transform: scale(1.06);
}

/* 站名与 slogan */
.header-text {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.site-name {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-strong);
    letter-spacing: 0.01em;
    line-height: 1.25;
}

.site-name ruby rt {
    font-size: 0.6875rem;
    font-weight: 400;
    color: var(--text-faint);
    letter-spacing: 0.05em;
}

.site-slogan {
    font-size: 0.8125rem;
    color: var(--text-muted);
}

.site-yiyan {
    font-size: 0.8125rem;
    color: var(--text-faint);
    font-style: italic;
    margin-top: 0.25rem;
}

/* ============================================================
   搜索框：极简底线式
   ============================================================ */
.search-wrap {
    position: relative;
    border-bottom: 1px solid var(--border-color);
    transition: border-color .3s ease;
}

.search-wrap:focus-within {
    border-color: var(--accent-color);
}

.search-input {
    width: 100%;
    padding: 0.5rem 2.25rem 0.5rem 0;
    border: none;
    background: transparent;
    font-family: var(--font-sans);
    font-size: 0.9375rem;
    color: var(--text-strong);
    outline: none;
}

.search-input::placeholder {
    color: var(--text-fainter);
}

.search-icon {
    position: absolute;
    right: 0.25rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-fainter);
    border: none;
    background: transparent;
    padding: 0.25rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    cursor: pointer;
    transition: color .3s ease;
}

.search-icon:hover {
    color: var(--accent-color);
}

.search-wrap:focus-within .search-icon {
    color: var(--accent-color);
}

/* 搜索栏：输入框 + 右侧搜索目的菜单 */
.search-bar {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.search-bar .search-wrap {
    flex: 1;
    min-width: 0;
}

/* 搜索目的菜单（下拉） */
.search-menu {
    position: relative;
    flex-shrink: 0;
}

.search-menu-btn {
    display: flex;
    align-items: center;
    gap: 0.375rem;
    font-size: 0.75rem;
    font-family: var(--font-sans);
    color: var(--text-muted);
    padding: 0.25rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    background: transparent;
    cursor: pointer;
    white-space: nowrap;
    transition: all .25s ease;
}

.search-menu-btn:hover {
    color: var(--accent-color);
    border-color: var(--accent-color);
}

.search-menu-chevron {
    transition: transform .25s ease;
}

.search-menu.open .search-menu-chevron {
    transform: rotate(180deg);
}

.search-menu-dropdown {
    position: absolute;
    top: calc(100% + 0.5rem);
    right: 0;
    min-width: 13rem;
    background: var(--bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08);
    padding: 0.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.125rem;
    z-index: 30;
}

/* 覆盖 display:flex，确保 hidden 属性真正隐藏菜单 */
.search-menu-dropdown[hidden] {
    display: none;
}

.search-menu-group {
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--text-fainter);
    padding: 0.5rem 0.625rem 0.25rem;
}

.search-menu-group:first-child {
    padding-top: 0.25rem;
}

.search-menu-item {
    text-align: left;
    font-size: 0.8125rem;
    font-family: var(--font-sans);
    color: var(--text-body);
    padding: 0.375rem 0.625rem;
    border: none;
    background: transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    white-space: nowrap;
    transition: all .2s ease;
}

.search-menu-item:hover {
    color: var(--accent-color);
    background: var(--accent-color-faint);
}

.search-menu-item.active {
    color: var(--accent-color);
    background: var(--accent-color-faint);
}

/* ============================================================
   分类导航：胶囊小标签
   ============================================================ */
.cat-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 0.375rem;
}

.cat-nav a {
    font-size: 0.75rem;
    color: var(--text-muted);
    padding: 0.2rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    transition: all .25s ease;
}

.cat-nav a:hover {
    color: var(--accent-color);
    border-color: var(--accent-color);
    background: var(--accent-color-faint);
}

/* ============================================================
   内容分组：大分类标题
   ============================================================ */
.site-main {
    display: flex;
    flex-direction: column;
    gap: 3rem;
}

.content-group {
    display: flex;
    flex-direction: column;
    gap: 1.75rem;
    scroll-margin-top: 5rem;
}

.group-title {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 0.8125rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    color: var(--text-muted);
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border-color);
}

/* 回到顶部按钮：移入小标题栏时淡入显示 */
.back-top-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    font-size: 0.6875rem;
    font-family: var(--font-sans);
    font-weight: 500;
    text-transform: none;
    letter-spacing: 0.02em;
    color: var(--text-faint);
    background: transparent;
    border: 1px solid transparent;
    border-radius: 999px;
    padding: 0.2rem 0.6rem;
    cursor: pointer;
    opacity: 0;
    transform: translateY(3px);
    transition: opacity .25s ease, color .25s ease, border-color .25s ease, transform .25s ease;
}

.group-title:hover .back-top-btn {
    opacity: 1;
    transform: translateY(0);
}

.back-top-btn:hover {
    color: var(--accent-color);
    border-color: var(--border-color);
}

.sub-group {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.sub-title {
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--text-faint);
    letter-spacing: 0.1em;
    padding-left: 0.25rem;
}

/* ============================================================
   核心特效：悬停弹性指示器（HoverListIndicator）
   ============================================================ */
.hover-list {
    position: relative;
    z-index: 0;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.75rem;
    min-width: 0;
}

/* 网站列表 2~4 列自适应 */
@media (min-width: 768px) {
    .hover-list {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

@media (min-width: 992px) {
    .hover-list {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
}

.hover-indicator {
    position: absolute;
    top: 0;
    left: 0;
    width: 0;
    height: 0;
    z-index: -1;
    border-radius: var(--radius-md);
    background: var(--hover-bg);
    opacity: 0;
    pointer-events: none;
    will-change: transform, width, height, opacity;
    transition:
        transform .48s cubic-bezier(.25, 1.22, .45, 1.04),
        width .4s cubic-bezier(.25, 1, .3, 1),
        height .4s cubic-bezier(.25, 1, .3, 1),
        opacity .25s ease-out;
}

.hover-item {
    position: relative;
    z-index: 1;
    min-width: 0;
    display: flex;
    align-items: center;
    gap: 0.875rem;
    padding: 0.5rem 0.75rem;
    border-radius: var(--radius-md);
    opacity: 1;
    transition: opacity .25s ease-out;
}

/* 悬停一项时，其余项变暗 50%*/
@media (hover: hover) {
    .hover-list:has(.hover-item:hover) .hover-item:not(:hover) {
        opacity: .5;
    }
}

.item-logo {
    width: 30px;
    height: 30px;
    flex-shrink: 0;
    border-radius: var(--radius-sm);
    object-fit: contain;
    background: #f7f7f7;
    padding: 3px;
    border: 1px solid #f0f0f0;
    transition: transform .3s cubic-bezier(.34, 1.56, .64, 1);
}

.hover-item:hover .item-logo {
    transform: scale(1.12);
}

.item-info {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 0.125rem;
}

.item-title {
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-strong);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    transition: color .3s ease;
}

.hover-item:hover .item-title {
    color: var(--text-title);
}

.item-desc {
    font-size: 0.8125rem;
    color: var(--text-muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.item-arrow {
    flex-shrink: 0;
    color: var(--text-faint);
    opacity: 0;
    transform: translate(-4px, 4px);
    transition: all .25s ease;
}

.hover-item:hover .item-arrow {
    opacity: 1;
    transform: translate(0, 0);
    color: var(--accent-color);
}

/* ============================================================
   搜索无结果提示
   ============================================================ */
.search-empty {
    text-align: center;
    color: var(--text-faint);
    font-size: 0.9375rem;
    padding: 3rem 0;
}

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    font-size: 0.8125rem;
    color: var(--text-faint);
    text-align: center;
}

.footer-copyright a {
    color: var(--accent-color);
    border-bottom: 1px solid transparent;
    transition: border-color .25s ease;
}

.footer-copyright a:hover {
    border-color: var(--accent-color);
}

/* ============================================================
   返回顶部按钮
   ============================================================ */
.go-top {
    position: fixed;
    right: 1.75rem;
    bottom: 1.75rem;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--bg);
    border: 1px solid var(--border-color);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    cursor: pointer;
    opacity: 0;
    pointer-events: none;
    transition: all .3s ease;
    z-index: 50;
}

.go-top.show {
    opacity: 1;
    pointer-events: auto;
}

.go-top:hover {
    color: var(--accent-color);
    border-color: var(--accent-color);
    transform: translateY(-2px);
}

/* ============================================================
   单页 / 404
   ============================================================ */
.page-main {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.page-title {
    font-size: 1.625rem;
    font-weight: 600;
    color: var(--text-strong);
    letter-spacing: 0.01em;
}

.page-content {
    font-size: 0.9375rem;
    line-height: 1.8;
    color: var(--text-body);
}

.page-content a {
    color: var(--accent-color);
    border-bottom: 1px solid var(--accent-color-light);
    transition: border-color .25s ease;
}

.page-content a:hover {
    border-color: var(--accent-color);
}

.page-content h1, .page-content h2, .page-content h3, .page-content h4 {
    color: var(--text-strong);
    margin: 1.5rem 0 0.75rem;
    font-weight: 600;
}

.page-content p {
    margin: 0.75rem 0;
}

.page-content img {
    border-radius: var(--radius-md);
    margin: 1rem 0;
}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 480px) {
    .container {
        padding: 2rem 1rem 4rem;
    }

    .site-header {
        gap: 1rem;
    }

    .sticky-back-btn-wrapper {
        width: 48px;
        height: 48px;
        top: 1rem;
    }

    /* 标题栏改为纵向排列，避免站名/slogan/一言挤在一行 */
    .header-titlebar {
        flex-direction: column;
        align-items: flex-start;
        column-gap: 0;
        row-gap: 0.125rem;
    }

    .header-titlebar .site-yiyan {
        margin-left: 0;
        max-width: 100%;
    }

    .site-name {
        font-size: 1.25rem;
    }

    /* 搜索框占满整行，搜索目的按钮换行右对齐 */
    .search-bar {
        flex-wrap: wrap;
        gap: 0.5rem;
    }

    .search-bar .search-wrap {
        flex-basis: 100%;
    }

    .search-menu {
        margin-left: auto;
    }

    .item-logo {
        width: 26px;
        height: 26px;
    }

    .item-title {
        font-size: 0.875rem;
    }

    .item-desc {
        font-size: 0.75rem;
    }
}

/* 超窄屏：列表改为单列，避免两列过窄导致文字严重截断 */
@media (max-width: 360px) {
    .hover-list {
        grid-template-columns: 1fr;
    }
}

/* 减少动效偏好 */
@media (prefers-reduced-motion: reduce) {
    .hover-indicator {
        transition: none;
    }

    .parallax-inner {
        transition: none;
    }
}

/* ============================================================
   深色模式：跟随系统 prefers-color-scheme，自动实时同步
   ============================================================ */
@media (prefers-color-scheme: dark) {
    :root {
        color-scheme: dark;

        --bg: #1a1a1a;

        /* 鼠尾草绿强调色在深色底上适当提亮 */
        --accent-color: #8aa99c;
        --accent-color-darker: color-mix(in srgb, var(--accent-color) 70%, #fff);
        --accent-color-light: color-mix(in srgb, var(--accent-color) 35%, #1a1a1a);
        --accent-color-faint: color-mix(in srgb, var(--accent-color) 14%, #1a1a1a);

        /* 文字色阶整体反转为浅色系 */
        --text-strong: #e8e8e8;
        --text-title: #f5f5f5;
        --text-body: #c9c9c9;
        --text-muted: #9a9a9a;
        --text-faint: #757575;
        --text-fainter: #6e6e6e;

        --border-color: #2e2e2e;
        --hover-bg: #242424;
    }

    body {
        transition: background-color .3s ease, color .3s ease;
    }

    /* 头像外圈阴影反白 */
    .avatar-circle {
        box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.08);
    }

    /* 网站 logo 占位底：深色块 */
    .item-logo {
        background: #262626;
        border-color: #333333;
    }

    /* 下拉面板与悬浮按钮阴影加深 */
    .search-menu-dropdown {
        box-shadow: 0 12px 32px rgba(0, 0, 0, 0.5);
    }

    .go-top {
        box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4);
    }
}