:root {
    --bg-page: #f7f9fc;
    --bg-panel: #ffffff;
    --bg-soft: #f1f4f9;
    --border: #dfe6ef;
    --border-strong: #c3cfdd;
    --text-main: #1f2937;
    --text-secondary: #4b5563;
    --text-muted: #94a3b8;
    --accent: #2b50c7;
    --accent-light: #d7e4ff;
    --accent-soft: #f1f5ff;
    --radius-lg: 22px;
    --radius-md: 16px;
    --radius-sm: 10px;
    --shadow-md: 0 22px 44px rgba(15, 30, 64, 0.08);
    --shadow-sm: 0 12px 24px rgba(15, 30, 64, 0.06);
    --transition: all 0.25s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: "Inter", "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--bg-page);
    color: var(--text-main);
    line-height: 1.7;
    min-height: 100vh;
}

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

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

ol, ul {
    list-style: none;
}

.page-shell {
    display: grid;
    grid-template-columns: minmax(260px, 320px) 1fr;
    max-width: 1280px;
    margin: 0 auto;
    gap: 36px;
    padding: 40px clamp(24px, 4vw, 48px) 80px;
}

.profile-sidebar {
    position: sticky;
    top: 40px;
    align-self: start;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.profile-card {
    background: var(--bg-panel);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    padding: 32px 28px;
    display: grid;
    gap: 18px;
}

.avatar-frame {
    width: 140px;
    height: 140px;
    border-radius: 50%;
    overflow: hidden;
    border: 3px solid var(--accent-light);
    margin: 0 auto;
}

.avatar {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.profile-name {
    text-align: center;
    font-size: 1.6rem;
    font-weight: 700;
}

.profile-role {
    text-align: center;
    color: var(--accent);
    font-size: 1rem;
}

.profile-bio {
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.profile-meta {
    display: grid;
    gap: 12px;
    font-size: 0.95rem;
}

.profile-meta li {
    display: flex;
    gap: 10px;
    align-items: center;
    color: var(--text-secondary);
}

.profile-meta i {
    color: var(--accent);
}

.profile-meta a {
    color: var(--accent);
    font-weight: 600;
}

.profile-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.action-link {
    flex: 1;
    min-width: 110px;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    background: var(--accent);
    color: #ffffff;
    text-align: center;
    font-size: 0.9rem;
    font-weight: 600;
    transition: var(--transition);
}

.action-link:nth-of-type(2) {
    background: var(--bg-soft);
    color: var(--accent);
    border: 1px solid var(--accent-light);
}

.action-link:hover {
    transform: translateY(-3px);
}

.content-area {
    display: grid;
    gap: 32px;
}

.top-bar {
    position: sticky;
    top: 0;
    z-index: 10;
    background: linear-gradient(180deg, rgba(247, 249, 252, 0.94), rgba(247, 249, 252, 0.85));
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

.top-nav ul {
    display: flex;
    flex-wrap: wrap;
    gap: 12px 18px;
    padding: 16px;
    justify-content: center;
}

.top-nav a {
    font-size: 0.9rem;
    color: var(--text-secondary);
    transition: var(--transition);
}

.top-nav a:hover {
    color: var(--accent);
}

.section-block {
    background: var(--bg-panel);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    padding: clamp(28px, 4vw, 40px);
    display: grid;
    gap: 16px;
}

.section-heading {
    display: flex;
    gap: 12px;
    align-items: center;
    flex-wrap: wrap;
}

.section-title {
    font-size: 1.6rem;
    font-weight: 700;
}

.section-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    letter-spacing: 0.08rem;
    padding: 6px 14px;
    border-radius: 999px;
    background: var(--accent-soft);
    color: #0fb4f5;
}

.section-description {
    color: var(--text-secondary);
    font-size: 0.98rem;
}

.section-description a {
    color: var(--accent);
    font-weight: 600;
}

.section-description a:hover {
    text-decoration: underline;
}

.item-list {
    display: grid;
    gap: 18px;
    font-size: 0.97rem;
    color: var(--text-secondary);
}

.item-list li {
    display: grid;
    gap: 6px;
}

.item-heading {
    font-weight: 600;
    color: var(--text-main);
}

.item-meta {
    font-size: 0.88rem;
    color: var(--text-muted);
}

.item-meta a {
    color: var(--accent);
    font-weight: 600;
}

.item-description {
    font-size: 0.95rem;
}

.item-list.bullets {
    gap: 10px;
}

.item-list.bullets li {
    position: relative;
    padding-left: 18px;
}

.item-list.bullets li::before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--accent);
}

.timeline-list {
    display: grid;
    gap: 22px;
    border-left: 2px solid var(--border);
    padding-left: 24px;
}

.timeline-list li {
    position: relative;
    display: grid;
    gap: 6px;
}

.timeline-list li::before {
    content: "";
    position: absolute;
    left: -31px;
    top: 6px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 0 5px var(--accent-light);
}

.timeline-title {
    font-weight: 600;
}

.timeline-meta {
    font-size: 0.88rem;
    color: var(--text-muted);
}

.timeline-description {
    color: var(--text-secondary);
    font-size: 0.96rem;
}

.timeline-description a {
    color: var(--accent);
    font-weight: 600;
}

.timeline-description a:hover {
    text-decoration: underline;
}

.timeline-bullets {
    display: grid;
    gap: 6px;
    padding-left: 18px;
    list-style: disc;
}

.contact-grid {
    display: grid;
    gap: 16px;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.contact-card {
    display: flex;
    gap: 14px;
    align-items: center;
    padding: 16px 18px;
    border-radius: var(--radius-md);
    background: var(--bg-soft);
    border: 1px solid var(--accent-light);
    color: var(--text-secondary);
}

.contact-card i {
    font-size: 1.2rem;
    color: var(--accent);
}

.contact-label {
    display: block;
    font-size: 0.82rem;
    letter-spacing: 0.12rem;
    text-transform: uppercase;
    color: var(--text-muted);
}

.contact-card a {
    color: var(--accent);
    font-weight: 600;
}

.site-footer {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

.back-to-top {
    position: fixed;
    bottom: 28px;
    right: 28px;
    width: 48px;
    height: 48px;
    border-radius: 14px;
    background: var(--accent);
    color: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: var(--shadow-sm);
    transform: translateY(20px);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 20;
}

.back-to-top.visible {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-4px);
}

@media (max-width: 1024px) {
    .page-shell {
        grid-template-columns: 1fr;
        gap: 28px;
    }

    .profile-sidebar {
        position: static;
        justify-content: center;
    }

    .profile-card {
        max-width: 360px;
        margin: 0 auto;
    }

    .profile-actions {
        justify-content: center;
    }
}

@media (max-width: 640px) {
    .top-nav ul {
        justify-content: flex-start;
        overflow-x: auto;
        scrollbar-width: none;
    }

    .top-nav ul::-webkit-scrollbar {
        display: none;
    }

    .action-link {
        flex: 1 1 45%;
        min-width: unset;
    }

    .profile-card {
        text-align: center;
    }

    .profile-meta li {
        justify-content: center;
    }
}