/* ==========================================================================
 * about.css — 自我介绍页
 * 主题：默认浅色，深色由 <html data-theme="dark"> 激活（切换逻辑见 js/theme.js）
 * ========================================================================== */

/* ---- 主题变量（默认浅色） ---- */
:root {
    color-scheme: light;           /* 滚动条 / 表单控件跟随主题 */
    --bg: #eef0f4;
    --surface: #ffffff;
    --surface-2: #f2f4f8;
    --text: #1c1e21;
    --text-secondary: #5d6470;
    --border: rgba(15, 23, 42, 0.08);

    --navbar-bg: #ffffff;
    --navbar-text: #3a3f47;
    --navbar-border: rgba(0, 0, 0, 0.12);
    --accent: #2563eb;

    --footer-text: #6b7280;
    --footer-link: #2563eb;
    --footer-link-hover: #1d4ed8;

    --shadow-card: 0 4px 12px rgba(15, 23, 42, 0.1);
}

/* ---- 深色主题 ---- */
:root[data-theme="dark"] {
    color-scheme: dark;

    --bg: #121212;
    --surface: #1e1e24;
    --surface-2: #27272e;
    --text: #e8e8ec;
    --text-secondary: #a0a6b0;
    --border: rgba(255, 255, 255, 0.09);

    --navbar-bg: #17171c;
    --navbar-text: #d6d9de;
    --navbar-border: rgba(255, 255, 255, 0.16);
    --accent: #6ea8fe;

    --footer-text: #9aa0a8;
    --footer-link: #8ab4f8;
    --footer-link-hover: #a8c8fb;

    --shadow-card: 0 4px 12px rgba(0, 0, 0, 0.35);
}

/* 主题切换平滑过渡 */
body,
nav,
.navbar-brand,
.nav-link,
.navbar-toggler,
.about-title,
.about-card,
.about-hello,
.about-tagline,
.about-bio,
.about-section__title,
.about-tags li,
.about-links a,
footer,
footer a {
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

/* ---- 基础 ---- */
body {
    background-color: var(--bg);
    color: var(--text);
    font-family: 'JetBrainsMono-Medium', 'Consolas', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    /* 抬到粒子画布之上（#particles-js 为 z-index:-1） */
    position: relative;
    z-index: 1;
}

/* ---- 粒子背景 ---- */
#particles-js {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background-color: var(--bg);
}

/* ---- 导航栏（与首页 / 留言板一致的主题导航） ---- */
.site-navbar {
    background: var(--navbar-bg);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.site-navbar .navbar-brand,
.site-navbar .nav-link {
    color: var(--navbar-text);
}

.site-navbar .nav-link:hover,
.site-navbar .nav-link:focus-visible,
.site-navbar .nav-item.active .nav-link {
    color: var(--accent);
}

.site-navbar .navbar-toggler {
    border-color: var(--navbar-border);
}

/* 导航按钮水平居中：菜单区占满剩余宽度，按钮组居中（桌面端） */
.site-navbar .navbar-collapse {
    flex-grow: 1;
    justify-content: center;
}

.site-navbar .navbar-nav {
    align-items: center;
}

.site-navbar .navbar-toggler-icon {
    background-color: var(--navbar-text);
    -webkit-mask: url("data:image/svg+xml,%3csvg viewBox='0 0 30 30' xmlns='http://www.w3.org/2000/svg'%3e%3cpath stroke='rgba(0,0,0,0.5)' stroke-width='2' stroke-linecap='round' stroke-miterlimit='10' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e") center / contain no-repeat;
    mask: url("data:image/svg+xml,%3csvg viewBox='0 0 30 30' xmlns='http://www.w3.org/2000/svg'%3e%3cpath stroke='rgba(0,0,0,0.5)' stroke-width='2' stroke-linecap='round' stroke-miterlimit='10' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e") center / contain no-repeat;
}

.logo {
    max-height: 30px;
    width: auto;
    margin: 0 10px;
}

/* ---- 页面标题 ---- */
.about-title {
    margin: 40px auto 0;
    color: var(--text);
    text-align: center;
    font-size: 2.5rem;
    font-style: italic;
    font-weight: bold;
}

/* ---- 主体容器 ---- */
.about-page {
    max-width: 880px;
    margin: 0 auto;
    padding: 0 16px;
}

/* ---- 简介卡：头像 + 姓名 + 正文 ---- */
.about-card {
    margin-top: 28px;
    padding: 32px;
    background: var(--surface);
    border-radius: 12px;
    box-shadow: var(--shadow-card);
}

.about-profile {
    display: flex;
    align-items: center;
    gap: 28px;
}

/* 圆形裁剪 + object-fit：日后换成非正方形照片也不会变形 */
.about-avatar {
    flex: 0 0 auto;
    width: 140px;
    height: 140px;
    border-radius: 50%;
    object-fit: cover;
    background: var(--surface-2);
    border: 3px solid var(--border);
}

.about-headline {
    min-width: 0;
}

.about-hello {
    margin: 0 0 8px;
    color: var(--text);
    font-size: 1.75rem;
    font-weight: bold;
}

.about-tagline {
    margin: 0;
    color: var(--text-secondary);
    font-size: 1rem;
    letter-spacing: 0.05em;
}

.about-bio {
    margin-top: 28px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
}

.about-bio p {
    margin: 0 0 16px;
    color: var(--text);
    font-size: 1rem;
    line-height: 1.9;
}

.about-bio p:last-child {
    margin-bottom: 0;
    color: var(--text-secondary);
}

/* ---- 兴趣 / 找到我 分区 ---- */
.about-section {
    margin-top: 36px;
}

.about-section__title {
    margin-bottom: 16px;
    color: var(--text);
    font-size: 1.25rem;
    font-weight: bold;
}

.about-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 0;
    padding: 0;
    list-style: none;
}

.about-tags li {
    padding: 7px 16px;
    color: var(--text);
    font-size: 0.9rem;
    background: var(--surface-2);
    border: 1px solid var(--border);
    border-radius: 999px;
}

.about-links {
    display: flex;
    flex-wrap: wrap;
    gap: 12px 24px;
}

.about-links a {
    position: relative;
    color: var(--accent);
    font-size: 1rem;
    text-decoration: none;
}

.about-links a::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -3px;
    width: 100%;
    height: 1px;
    background: currentColor;
    transform: scaleX(0);
    transform-origin: left center;
    transition: transform 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}

.about-links a:hover::after,
.about-links a:focus-visible::after {
    transform: scaleX(1);
}

/* ---- 页脚 ---- */
footer {
    color: var(--footer-text);
}

footer a {
    color: var(--footer-link);
}

footer a:hover,
footer a:focus {
    color: var(--footer-link-hover);
}

footer .language-switcher {
    margin-top: 10px;
    text-align: center;
    display: flex;
    justify-content: center;
    gap: 10px;
}

footer .language-switcher button {
    transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

footer .language-switcher button:hover {
    transform: translateY(-2px);
}

/* ---- 语言切换的淡入淡出（js/aboutlang.js 添加这两个类） ---- */
.fade-out {
    animation: fadeOut 0.4s cubic-bezier(0.7, 0, 0.84, 0) forwards;
}

.fade-in {
    animation: fadeIn 0.5s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes fadeOut {
    from { opacity: 1; }
    to   { opacity: 0; }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* ---- 页面加载动画（非线性缓动） ---- */
.about-title {
    animation: riseFadeIn 0.7s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.about-card {
    animation: zoomFadeIn 0.7s cubic-bezier(0.34, 1.56, 0.64, 1) 0.15s both;
}

.about-section {
    animation: riseFadeIn 0.7s cubic-bezier(0.16, 1, 0.3, 1) both;
}

/* <section> 同级中：1 = 简介卡，2 / 3 = 兴趣与找到我，依次延后入场 */
.about-section:nth-of-type(2) { animation-delay: 0.3s; }
.about-section:nth-of-type(3) { animation-delay: 0.4s; }

@keyframes riseFadeIn {
    from { opacity: 0; transform: translateY(24px); }
    to   { opacity: 1; transform: translateY(0); }
}

@keyframes zoomFadeIn {
    from { opacity: 0; transform: scale(0.96); }
    to   { opacity: 1; transform: scale(1); }
}

/* 尊重"减少动态效果"偏好 */
@media (prefers-reduced-motion: reduce) {
    .about-title,
    .about-card,
    .about-section {
        animation: none !important;
        opacity: 1 !important;
        transform: none !important;
    }

    .fade-out,
    .fade-in {
        animation: none !important;
    }
}

/* ---- 小屏适配 ---- */
@media (max-width: 768px) {
    .about-page {
        padding: 0 12px;
    }

    .about-title {
        font-size: 2rem;
    }

    .about-card {
        padding: 24px 20px;
    }

    /* 头像与姓名改为上下堆叠 */
    .about-profile {
        flex-direction: column;
        text-align: center;
        gap: 18px;
    }

    .about-avatar {
        width: 120px;
        height: 120px;
    }

    .about-links {
        flex-direction: column;
        gap: 12px;
    }
}

/* 折叠断点（<992px）：移动端/平板菜单项居中 */
@media (max-width: 991.98px) {
    .site-navbar .navbar-collapse {
        justify-content: center;
    }

    .site-navbar .navbar-nav {
        align-items: center;
        text-align: center;
    }

    .site-navbar .navbar-nav .nav-link {
        text-align: center;
    }
}