:root {
    --color-heading: #15181d;
    --color-body: #39424e;
    --color-muted: #596574;
    --color-accent: #1f6faf;
    --color-accent-dark: #155686;
    --color-focus: #0b5f8a;
    --color-paper: #f7f8fa;
    --color-surface: #ffffff;
    --color-tint: #f0f3f6;
    --color-border: #dde3e8;
    --font-body: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    --nav-height: 68px;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--color-paper);
    color: var(--color-body);
    font-family: var(--font-body);
    font-size: 16px;
    font-weight: 400;
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
}

a {
    color: var(--color-accent);
    text-decoration-thickness: 1px;
    text-underline-offset: 0.2em;
}

a:hover {
    color: var(--color-accent-dark);
}

:focus-visible {
    border-radius: 2px;
    outline: 3px solid var(--color-focus);
    outline-offset: 4px;
}

.skip-link {
    position: fixed;
    top: 12px;
    left: 12px;
    z-index: 1100;
    padding: 0.65rem 1rem;
    background: var(--color-heading);
    color: #fff;
    transform: translateY(-150%);
    transition: transform 160ms ease-out;
}

.skip-link:focus {
    color: #fff;
    transform: translateY(0);
}

.site-container {
    width: min(100% - 48px, 1080px);
    padding-right: 0;
    padding-left: 0;
}

.site-nav {
    min-height: var(--nav-height);
    border-bottom: 1px solid var(--color-border);
    background: var(--color-paper);
}

.navbar-brand {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    color: var(--color-heading);
    font-size: 1.05rem;
    font-weight: 650;
    letter-spacing: -0.01em;
}

.navbar-brand:hover,
.navbar-brand:focus {
    color: var(--color-accent-dark);
}

.site-nav .nav-link {
    position: relative;
    min-height: 44px;
    margin-left: 1.5rem;
    padding: 0.75rem 0.1rem;
    color: var(--color-muted);
    font-size: 0.82rem;
    font-weight: 650;
    letter-spacing: 0.055em;
    text-transform: uppercase;
}

.site-nav .nav-link::after {
    position: absolute;
    right: 0;
    bottom: 0.45rem;
    left: 0;
    height: 2px;
    background: var(--color-accent);
    content: "";
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 180ms ease-out;
}

.site-nav .nav-link:hover,
.site-nav .nav-link.active {
    color: var(--color-heading);
}

.site-nav .nav-link:hover::after,
.site-nav .nav-link.active::after {
    transform: scaleX(1);
}

.navbar-toggler {
    display: inline-flex;
    align-items: center;
    min-width: 44px;
    min-height: 44px;
    gap: 0.35rem;
    border: 1px solid var(--color-border);
    color: var(--color-heading);
    font-size: 0.78rem;
    font-weight: 650;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}

h1,
h2,
h3 {
    color: var(--color-heading);
    font-family: var(--font-body);
}

h1,
h2 {
    font-weight: 700;
    letter-spacing: -0.025em;
}

.profile-intro {
    display: grid;
    grid-template-columns: 260px minmax(0, 1fr);
    align-items: start;
    width: min(100% - 48px, 1080px);
    gap: clamp(3rem, 7vw, 5.5rem);
    margin: 0 auto;
    padding: calc(var(--nav-height) + 5.5rem) 0 6rem;
    scroll-margin-top: var(--nav-height);
}

.portrait-wrap {
    margin: 0;
}

.portrait-wrap img {
    display: block;
    width: 100%;
    height: auto;
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    object-fit: contain;
}

.profile-intro__body {
    max-width: 700px;
}

.profile-intro h1 {
    margin: -0.15em 0 0;
    font-size: clamp(2.5rem, 5vw, 4rem);
    line-height: 1.08;
}

.profile-name-zh {
    margin: 0.45rem 0 0;
    color: var(--color-heading);
    font-size: 1.3rem;
    font-weight: 600;
}

.profile-role {
    margin: 1.15rem 0 1.7rem;
    color: var(--color-accent-dark);
    font-size: 0.9rem;
    font-weight: 650;
    letter-spacing: 0.07em;
    text-transform: uppercase;
}

.profile-bio,
.prose p {
    max-width: 70ch;
}

.profile-bio {
    margin: 0 0 0.85rem;
    font-size: 1.02rem;
}

.profile-bio-zh {
    color: var(--color-muted);
}

.prose {
    max-width: 70ch;
}

.profile-intro .prose {
    margin-top: 2rem;
    padding-top: 1.75rem;
    border-top: 1px solid var(--color-border);
}

.prose h2 {
    margin: 0 0 1rem;
    font-size: 1.25rem;
    line-height: 1.35;
}

.prose p {
    margin: 0 0 1rem;
}

.prose p:last-child {
    margin-bottom: 0;
}

.section {
    padding: 5.5rem 0;
    scroll-margin-top: var(--nav-height);
}

.section-tinted {
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
    background: var(--color-tint);
}

.section-heading {
    margin-bottom: 2.5rem;
}

.section-heading h2,
.profile-contact h2 {
    margin: 0;
    font-size: clamp(1.8rem, 3vw, 2.4rem);
    line-height: 1.25;
}

.section-heading h2 span,
.profile-contact h2 span {
    color: var(--color-muted);
    font-weight: 600;
}

.interest-list,
.education-list {
    max-width: 920px;
    margin: 0;
    padding: 0;
    list-style: none;
}

.interest-row {
    display: grid;
    grid-template-columns: minmax(240px, 0.85fr) minmax(0, 1fr);
    align-items: baseline;
    gap: 2.5rem;
    padding: 1.45rem 0;
    border-top: 1px solid var(--color-border);
}

.interest-row:last-child {
    border-bottom: 1px solid var(--color-border);
}

.interest-row strong {
    color: var(--color-heading);
    font-size: 1rem;
    font-weight: 650;
}

.interest-row > span {
    color: var(--color-muted);
}

.education-row {
    display: grid;
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 2.5rem;
    padding: 1.65rem 0;
    border-top: 1px solid var(--color-border);
}

.education-row:last-child {
    border-bottom: 1px solid var(--color-border);
}

.education-row time {
    color: var(--color-accent-dark);
    font-size: 0.9rem;
    font-weight: 650;
}

.education-row p {
    max-width: 70ch;
    margin: 0;
}

.education-row p:first-child {
    color: var(--color-heading);
    font-weight: 600;
}

.education-row p + p {
    margin-top: 0.3rem;
    color: var(--color-muted);
}

.profile-contact {
    padding: 5.5rem 0 6rem;
    border-top: 1px solid var(--color-border);
    background: var(--color-surface);
    scroll-margin-top: var(--nav-height);
}

.profile-contact h2 {
    margin-bottom: 2rem;
}

.contact-strip {
    display: flex;
    flex-wrap: wrap;
    min-height: 64px;
    gap: 1.5rem;
    padding: 0.75rem 1rem;
    border: 1px solid var(--color-border);
    background: var(--color-surface);
}

.contact-strip a {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    overflow-wrap: anywhere;
    font-weight: 600;
}

.profile-contact > .site-container > p {
    max-width: 70ch;
    margin: 1.5rem 0 0;
}

.profile-contact > .site-container > p + p {
    margin-top: 0.2rem;
    color: var(--color-muted);
}

.site-footer {
    padding: 1.6rem 0;
    border-top: 1px solid var(--color-border);
    background: var(--color-paper);
    color: var(--color-muted);
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
}

.footer-inner p {
    margin: 0;
    font-size: 0.78rem;
}

.footer-meta {
    letter-spacing: 0.03em;
}

.site-footer :focus-visible {
    outline-color: #fff;
    box-shadow: 0 0 0 6px var(--color-focus);
}

.content-error {
    padding: 1rem;
    border-left: 3px solid #a33a3a;
    background: #fff3f3;
    color: #782b2b;
}

@media (max-width: 991.98px) {
    .profile-intro {
        grid-template-columns: 220px minmax(0, 1fr);
        gap: 40px;
    }
}

@media (max-width: 767.98px) {
    :root {
        --nav-height: 64px;
    }

    .site-container,
    .profile-intro {
        width: min(100% - 40px, 1080px);
    }

    .site-nav .navbar-collapse {
        margin: 0.75rem -20px -0.45rem;
        padding: 0.5rem 20px 1rem;
        border-top: 1px solid var(--color-border);
        background: var(--color-paper);
    }

    .site-nav .nav-link {
        margin-left: 0;
        padding: 0.75rem 0;
    }

    .site-nav .nav-link::after {
        right: auto;
        bottom: 0.55rem;
        width: 2rem;
    }

    .profile-intro {
        grid-template-columns: 1fr;
        gap: 2.5rem;
        padding: calc(var(--nav-height) + 3.5rem) 0 4.5rem;
    }

    .portrait-wrap {
        width: min(58vw, 210px);
        margin: 0 auto;
        transform: none;
    }

    .profile-intro h1 {
        font-size: clamp(2.35rem, 12vw, 3.2rem);
    }

    .section,
    .profile-contact {
        padding: 4.25rem 0;
    }

    .section-heading {
        margin-bottom: 2rem;
    }

    .interest-row,
    .education-row {
        grid-template-columns: 1fr;
        gap: 0.5rem;
    }

    .contact-strip {
        flex-direction: column;
        gap: 0.25rem;
    }

    .contact-strip a {
        width: 100%;
    }

    .footer-inner {
        align-items: flex-start;
        flex-direction: column;
        gap: 0.4rem;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        scroll-behavior: auto !important;
        transition-duration: 0.01ms !important;
    }
}