/* A quiet, notebook-like portfolio. All five pages share these primitives. */
:root {
    color-scheme: light;
    --ink: #30302e;
    --muted: #73736e;
    --line: #e9e9e5;
    --soft: #f7f7f5;
    --paper: #fff;
    --container: 1000px;
    --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", "Microsoft YaHei", sans-serif;
    --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 35px; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--font); font-size: 16px; line-height: 1.8; -webkit-font-smoothing: antialiased; }
[hidden] { display: none !important; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; }
a, button { -webkit-tap-highlight-color: transparent; }
button, a { touch-action: manipulation; }
a:focus-visible, button:focus-visible { outline: 2px solid #575752; outline-offset: 4px; border-radius: 3px; }
::selection { color: #232321; background: #e5e5df; }
h1, h2, h3, p, figure { margin: 0; }
h1, h2, h3 { line-height: 1.5; text-wrap: pretty; }
h1 { font-weight: 700; }
h2, h3, strong { font-weight: 600; }
img { display: block; max-width: 100%; height: auto; }
svg.icon { width: 18px; height: 18px; flex: 0 0 18px; display: inline-block; vertical-align: -3px; }
.container { width: min(var(--container), calc(100% - 64px)); margin-inline: auto; }
.skip-link { position: fixed; top: -70px; left: 24px; padding: 9px 17px; background: white; border: 1px solid var(--ink); z-index: 20; }
.skip-link:focus { top: 20px; }

/* Measurement marks stay outside the reading surface. */
.drawing-frame { position: fixed; inset: 0; pointer-events: none; z-index: -1; color: #aaa9a2; }
.drawing-frame::before, .drawing-frame::after { content: ""; position: absolute; top: 0; bottom: 0; width: 1px; background: #f0f0ed; }
.drawing-frame::before { left: calc(50% - var(--container) / 2 - 45px); }
.drawing-frame::after { right: calc(50% - var(--container) / 2 - 45px); }
.ruler { position: absolute; font: 8px/1 var(--mono); }
.ruler-top { left: calc(50% - var(--container) / 2); width: var(--container); top: 0; height: 15px; display: flex; justify-content: space-between; background: repeating-linear-gradient(90deg, #deded8 0 1px, transparent 1px 10px) bottom/100% 4px no-repeat; }
.ruler-top span { padding-top: 2px; }
.ruler-left { top: 92px; bottom: 32px; left: calc(50% - var(--container) / 2 - 59px); width: 14px; display: flex; flex-direction: column; justify-content: space-between; background: repeating-linear-gradient(180deg, #e0e0db 0 1px, transparent 1px 10px) right/4px 100% no-repeat; }
.ruler-left span { writing-mode: vertical-rl; transform: rotate(180deg); }
.margin-caption { position: absolute; right: calc(50% - var(--container) / 2 - 68px); bottom: 38px; writing-mode: vertical-rl; font: 8px/1 var(--mono); letter-spacing: .16em; }

/* Header: a breadcrumb on the left, quiet document tabs on the right. */
.site-header { padding-top: 20px; }
.nav-shell { position: relative; min-height: 62px; display: flex; align-items: center; justify-content: space-between; gap: 17px; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 10px; white-space: nowrap; font-size: 14px; }
.brand > .icon { width: 17px; height: 17px; }
.brand-separator { color: #c9c9c3; margin-inline: 1px; }
.brand-page { color: var(--muted); font-size: 13px; }
.nav-menu { display: flex; align-items: center; gap: 5px; margin: 0 0 0 auto; padding: 0; list-style: none; }
.nav-link { display: inline-flex; align-items: center; gap: 5px; padding: 5px 8px; font-size: 13px; color: var(--muted); border-radius: 4px; }
.nav-link .icon { width: 15px; height: 15px; flex-basis: 15px; }
.nav-link:hover { background: var(--soft); color: var(--ink); }
.nav-link.active { background: #f0f0ed; color: #343431; }
.nav-toggle { display: none; }
.language-toggle { display: inline-flex; align-items: center; justify-content: center; gap: 5px; flex: 0 0 auto; padding: 5px 8px; min-height: 36px; border: 1px solid var(--line); border-radius: 4px; background: white; color: #8a8a82; font-size: 12px; cursor: pointer; }
.language-toggle:hover { background: var(--soft); }
.language-toggle[data-language="zh"] [lang="zh-CN"], .language-toggle[data-language="en"] [lang="en"] { color: var(--ink); font-weight: 600; }
.language-divider { color: #c7c7bf; }
html[lang="en"] .title-en, html[lang="en"] .identity-title > span { display: none; }
html[lang="en"] .page-label { letter-spacing: .04em; }
html[lang="en"] .card h3 { line-height: 1.6; }

/* Title + introduction: intentionally human-sized, with an unframed ink portrait. */
.hero { padding-top: 51px; }
.page-heading { margin-bottom: 35px; }
.page-label { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; color: var(--muted); font-size: 12px; letter-spacing: .1em; }
.page-title { color: #292927; font-size: 40px; letter-spacing: -.035em; line-height: 1.35; }
.title-en { margin-left: 16px; color: #aaa9a2; font-size: 25px; font-weight: 400; letter-spacing: -.025em; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1fr) 275px; gap: 64px; align-items: center; }
.identity-title { font-size: 25px; line-height: 1.5; letter-spacing: -.03em; }
.identity-title span { display: block; margin-top: 2px; color: var(--muted); font-size: 14px; font-weight: 400; letter-spacing: 0; }
.hero-lede { max-width: 570px; margin-top: 15px; font-size: 15px; line-height: 1.9; }
.hero-meta { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 14px; }
.mini-tag, .tag, .status, .featured-repo-points span { display: inline-block; width: fit-content; padding: 1px 7px; border-radius: 3px; background: #f0f0ed; color: #62625b; font-size: 12px; line-height: 1.7; font-weight: 400; }
.actions { display: flex; gap: 9px; flex-wrap: wrap; margin-top: 21px; }
.button { display: inline-flex; justify-content: center; align-items: center; gap: 7px; padding: 5px 12px; min-height: 36px; background: white; border: 1px solid #deded9; border-radius: 4px; font-size: 13px; line-height: 1.6; box-shadow: 0 1px 2px #24242008; transition: background .15s, border-color .15s; }
.button .icon { width: 15px; height: 15px; flex-basis: 15px; }
.button:hover { background: var(--soft); border-color: #bdbdb5; }
.button-primary { font-weight: 500; }
.hero-socials { display: flex; flex-wrap: wrap; gap: 8px 18px; margin-top: 17px; }
.social-button { display: inline-flex; align-items: center; gap: 5px; color: #66665f; font-size: 13px; border-bottom: 1px solid transparent; }
.social-button .icon { width: 15px; height: 15px; flex-basis: 15px; }
.social-button:hover { color: var(--ink); border-bottom-color: #c8c8c2; }
.portrait-card { align-self: end; width: 100%; }
.portrait-card img { width: 245px; height: 305px; object-fit: contain; margin-inline: auto; }
.portrait-card figcaption { color: #999990; font-size: 10px; text-align: center; letter-spacing: .025em; margin-top: 5px; }

/* Compact database views with hairlines, monochrome labels and subtle depth. */
.section { padding-top: 45px; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 28px; margin-bottom: 15px; }
.section-kicker { display: none; }
.section-title { font-size: 22px; letter-spacing: -.025em; }
.section-note { max-width: 450px; color: var(--muted); font-size: 12px; line-height: 1.7; text-align: right; }
.section-heading .button { padding: 3px 8px; min-height: 30px; font-size: 12px; }
.database-toolbar, .filters, .page-index { display: flex; align-items: center; flex-wrap: wrap; gap: 3px 17px; border-bottom: 1px solid var(--line); margin-bottom: 15px; }
.database-toolbar > *, .filter-btn, .page-index a { display: inline-flex; align-items: center; gap: 5px; min-height: 40px; padding: 5px 2px; border: 0; border-bottom: 2px solid transparent; background: none; color: var(--muted); font-size: 13px; line-height: 1.6; cursor: pointer; }
.database-toolbar > span { cursor: default; }
.database-toolbar .current, .filter-btn.active { border-bottom-color: #53534e; color: var(--ink); }
.database-toolbar a:hover, .filter-btn:hover, .page-index a:hover { color: #222; background: var(--soft); }
.database-toolbar .icon, .filter-btn .icon, .page-index .icon { width: 15px; height: 15px; flex-basis: 15px; }
.card-grid, .stats-grid, .feature-grid, .timeline, .project-grid, .book-grid, .repo-grid, .works-grid { display: grid; gap: 14px; }
.card-grid, .repo-grid-three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.stats-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; }
.feature-grid, .timeline, .project-grid, .book-grid, .repo-grid, .works-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.repo-grid-three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.card, .stat-card, .feature-card, .timeline-card, .project-card, .book-card, .repo-card, .work-link-card, .featured-repo, .internship-card, .pub-item { min-width: 0; background: #fff; border: 1px solid var(--line); border-radius: 5px; box-shadow: 0 1px 3px #25251b07, 0 2px 8px #25251b03; }
.card { position: relative; padding: 16px; }
.card-icon { display: inline-flex; float: left; margin: 2px 8px 0 0; color: #606058; }
.card h3 { font-size: 14px; }
.card p { margin-top: 8px; font-size: 13px; line-height: 1.8; color: #71716a; }
.stat-card { padding: 14px 16px; }
.stat-number { font-size: 28px; font-weight: 600; line-height: 1.3; letter-spacing: -.05em; }
.stat-unit { font-size: 12px; font-weight: 400; color: var(--muted); letter-spacing: 0; margin-left: 2px; }
.stat-label { margin-top: 4px; font-size: 12px; color: var(--muted); }
.feature-card { padding: 20px; }
.feature-card h3 { margin: 10px 0 7px; font-size: 16px; }
.feature-card h3 .icon { margin-right: 7px; }
.feature-card p, .timeline-card p, .book-card p { font-size: 14px; line-height: 1.85; color: #73736b; }
.inline-link { display: inline-flex; align-items: center; gap: 8px; margin-top: 14px; font-size: 13px; text-decoration: underline; text-decoration-color: #d8d8d1; text-underline-offset: 4px; }
.inline-link:hover { text-decoration-color: currentColor; }
.timeline-card { padding: 18px; }
.timeline-date, .project-meta, .book-label, .repo-name, .repo-stat, .work-platform { font-size: 12px; color: var(--muted); }
.timeline-date { display: block; font-family: var(--mono); letter-spacing: -.02em; }
.timeline-card h3 { margin: 9px 0 7px; font-size: 14px; }

/* Inner pages use the same title scale, with no oversized hero panels. */
.page-hero { padding-top: 48px; }
.page-hero-panel { position: relative; padding-bottom: 28px; }
.page-lede { max-width: 785px; margin-top: 15px; font-size: 15px; color: #6a6a63; }
.quick-stats { display: flex; flex-wrap: wrap; gap: 5px 18px; margin-top: 16px; }
.quick-stat { font-size: 12px; color: #73736b; }
.quick-stat::before { content: "·"; margin-right: 8px; color: #a9a99f; }
.sheet-number { position: absolute; right: 0; top: 4px; color: #99998f; font: 11px/1.5 var(--mono); }
.illustrated { padding-right: 184px; }
.page-illustration { position: absolute; right: 8px; top: 30px; width: 145px; height: 110px; object-fit: contain; }
.page-index { margin-bottom: 0; gap: 21px; }
.page-hero + .section { padding-top: 29px; }

/* Publications */
.filters { margin-bottom: 28px; }
.collection-group + .collection-group { margin-top: 31px; }
.group-title { font-size: 16px; margin-bottom: 12px; }
.pub-list { display: grid; gap: 12px; }
.pub-item { display: grid; grid-template-columns: minmax(0, 1fr) 170px; gap: 23px; padding: 20px 21px; }
.pub-item > div:first-child { position: relative; padding-left: 29px; }
.pub-item > div:first-child > .icon { position: absolute; left: 0; top: 4px; color: #84847b; }
.pub-title { font-size: 15px; line-height: 1.75; margin-bottom: 7px; }
.pub-title-translation { display: block; margin-top: 5px; color: var(--muted); font-size: 13px; font-weight: 400; line-height: 1.75; letter-spacing: 0; }
.pub-authors { font-size: 13px; color: #696960; }
.pub-venue { font-size: 13px; color: #707068; margin-top: 3px; }
.pub-note { font-size: 12px; color: #74746a; margin-top: 5px; }
.pub-side { display: flex; flex-direction: column; align-items: flex-start; justify-content: center; gap: 7px; border-left: 1px solid #f0f0ec; padding-left: 18px; }
.status-award { background: #f1f1e9; color: #6a6b54; }
.status-review { background: #f2f2ef; color: #78796d; }

/* Research cards and books */
.project-card { position: relative; padding: 21px; }
.project-card > .icon { color: #727269; margin-right: 7px; }
.project-no { color: #99998e; font: 11px/1.5 var(--mono); }
.project-card h2 { font-size: 16px; margin: 12px 0 9px; }
.project-meta { line-height: 1.9; }
.project-card ul, .compact-list { margin: 14px 0 0; padding-left: 20px; font-size: 14px; color: #6a6a62; }
.project-card li, .compact-list li { padding-left: 2px; margin-bottom: 5px; line-height: 1.9; }
li::marker { color: #a0a096; }
.book-card { padding: 20px; }
.book-card > .icon { color: #6c6c61; margin-right: 8px; }
.book-label { vertical-align: 1px; }
.book-card h3 { margin: 12px 0 8px; font-size: 16px; }

/* Practice: dates in the margin, structured narratives in restrained panels. */
.internship-list { display: grid; gap: 16px; }
.internship-card { display: grid; grid-template-columns: 170px minmax(0, 1fr); gap: 25px; padding: 24px; }
.internship-aside { border-right: 1px solid #efefeb; padding-right: 15px; }
.internship-aside .timeline-date { font-size: 12px; }
.internship-index { display: flex; align-items: center; gap: 8px; color: #b0b0a5; font: 12px/1 var(--mono); margin-top: 16px; }
.internship-org { color: #78786e; font-size: 13px; margin-bottom: 5px; }
.internship-content h2 { font-size: 17px; }
.internship-project { margin-top: 16px; }
.internship-project h3 { font-size: 14px; margin-bottom: 4px; }
.internship-project p { color: #737369; font-size: 14px; line-height: 1.95; }
.internship-content > .compact-list { margin-top: 12px; }

/* Community works */
.featured-repo { display: grid; grid-template-columns: 250px minmax(0, 1fr); gap: 28px; padding: 26px; margin-bottom: 16px; }
.featured-repo-visual { display: flex; flex-direction: column; align-items: center; justify-content: center; padding-right: 25px; border-right: 1px solid var(--line); }
.featured-repo-logo { width: 100%; height: 138px; object-fit: contain; margin-bottom: 21px; }
.featured-repo-visual-actions { display: flex; flex-direction: column; gap: 8px; width: 100%; }
.featured-repo-copy h3 { margin: 10px 0; font-size: 20px; line-height: 1.65; letter-spacing: -.025em; }
.featured-repo-copy > p:not(.repo-name) { color: #73736a; font-size: 14px; line-height: 1.9; margin-top: 8px; }
.featured-repo-points { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 14px; }
.featured-repo-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 17px; }
.repo-card { display: flex; flex-direction: column; padding: 18px; }
.repo-name { overflow-wrap: anywhere; font-family: var(--mono); font-size: 11px; line-height: 1.75; }
.repo-card h3 { font-size: 15px; margin: 10px 0 7px; }
.repo-card h3 .icon { margin-right: 5px; width: 14px; height: 14px; }
.repo-card > p:not(.repo-name) { color: #73736a; font-size: 13px; line-height: 1.85; }
.repo-stat { margin-top: auto; padding-top: 15px; font-size: 11px; }
a.repo-card, a.work-link-card { transition: border-color .15s, background .15s; }
a.repo-card:hover, a.work-link-card:hover { border-color: #c6c6bc; background: #fcfcfa; }
.work-link-card { display: block; position: relative; padding: 18px 41px 18px 18px; }
.work-link-card h3 { font-size: 14px; margin-top: 7px; }
.work-link-card p { font-size: 13px; color: #707068; margin-top: 5px; }
.work-platform { display: inline-block; padding: 1px 5px; border-radius: 2px; background: #f2f2ee; font-size: 11px; }
.work-arrow { position: absolute; right: 15px; top: 17px; font-size: 16px; color: #96968b; }

/* Footer is part of the document, not another banner. */
.site-footer { margin-top: 60px; padding-bottom: 31px; }
.footer-shell { border-top: 1px solid var(--line); padding-top: 21px; display: flex; align-items: center; justify-content: space-between; gap: 23px; }
.footer-name { color: #707068; font-size: 12px; }
.footer-note { color: #a0a095; font-size: 11px; margin-top: 2px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 17px; font-size: 12px; color: #73736b; }
.footer-links a:hover { color: var(--ink); text-decoration: underline; }

@media (max-width: 1200px) {
    .drawing-frame::before { left: 17px; }
    .drawing-frame::after { right: 17px; }
    .ruler-left { left: 3px; }
    .margin-caption { right: 5px; }
    .ruler-top { left: 32px; width: calc(100% - 64px); }
}
@media (max-width: 1080px) {
    .language-toggle { margin-left: auto; }
    .nav-toggle { display: flex; flex-direction: column; justify-content: center; gap: 4px; width: 38px; height: 38px; padding: 9px; border: 1px solid var(--line); background: white; border-radius: 4px; cursor: pointer; }
    .bar { display: block; width: 16px; height: 1px; background: #55554c; }
    .nav-menu { display: none; position: absolute; top: 57px; right: 0; width: 240px; padding: 9px; background: white; border: 1px solid var(--line); border-radius: 5px; box-shadow: 0 6px 20px #2222110d; z-index: 10; }
    .nav-menu.active { display: flex; flex-direction: column; align-items: stretch; }
    .nav-link { display: flex; padding: 12px; font-size: 14px; }
    .hero-grid { grid-template-columns: minmax(0, 1fr) 240px; gap: 35px; }
    .portrait-card img { width: 215px; height: 280px; }
    .section-note { max-width: 300px; }
}
@media (max-width: 640px) {
    .brand-page, .brand-separator { display: none; }
    .container { width: calc(100% - 48px); }
    .site-header { padding-top: 14px; }
    .drawing-frame::before { left: 11px; }
    .drawing-frame::after { right: 11px; }
    .ruler-left, .margin-caption { display: none; }
    .ruler-top { left: 24px; width: calc(100% - 48px); opacity: .65; }
    .ruler-top span:nth-child(even) { visibility: hidden; }
    .hero, .page-hero { padding-top: 32px; }
    .page-heading { margin-bottom: 28px; }
    .page-title { font-size: 34px; }
    .title-en { font-size: 21px; margin-left: 12px; }
    .hero-grid { grid-template-columns: minmax(0, 1fr) 124px; gap: 16px; align-items: start; }
    .hero-grid > div { display: contents; }
    .identity-title { grid-column: 1; align-self: center; font-size: 22px; }
    .identity-title span { font-size: 12px; }
    .portrait-card { grid-column: 2; grid-row: 1; align-self: center; }
    .portrait-card img { width: 120px; height: 150px; }
    .portrait-card figcaption { display: none; }
    .hero-lede, .hero-meta, .actions, .hero-socials { grid-column: 1 / -1; margin-top: 0; }
    .hero-lede { font-size: 14px; }
    .hero-socials { gap: 12px 21px; }
    .section { padding-top: 36px; }
    .section-title { font-size: 20px; }
    .section-heading { flex-wrap: wrap; align-items: center; gap: 5px 14px; margin-bottom: 14px; }
    .section-note { max-width: none; text-align: left; font-size: 12px; }
    .section-heading .button { margin-left: auto; }
    .card-grid, .feature-grid, .timeline, .project-grid, .book-grid, .repo-grid, .repo-grid-three, .works-grid { grid-template-columns: 1fr; gap: 12px; }
    .stats-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .card { padding: 14px 16px; }
    .card p { margin-top: 5px; }
    .stat-card { padding: 13px 15px; }
    .stat-number { font-size: 26px; }
    .database-toolbar, .filters, .page-index { gap: 3px 14px; }
    .filter-btn { font-size: 12px; gap: 4px; }
    .page-index a { font-size: 12px; }
    .page-hero-panel { padding-bottom: 23px; }
    .page-lede { font-size: 14px; margin-top: 12px; }
    .page-label { font-size: 11px; }
    .illustrated { padding-right: 0; }
    .page-illustration { top: -9px; right: 0; width: 52px; height: 35px; opacity: .8; }
    .sheet-number { display: none; }
    .illustrated .page-label { padding-right: 81px; }
    .quick-stats { gap: 4px 14px; margin-top: 14px; }
    .quick-stat { font-size: 11px; }
    .pub-item { grid-template-columns: 1fr; gap: 14px; padding: 17px; }
    .pub-side { flex-direction: row; flex-wrap: wrap; border-left: 0; border-top: 1px solid #f0f0ec; padding: 12px 0 0 29px; }
    .pub-title { font-size: 14px; }
    .internship-card { grid-template-columns: 1fr; gap: 14px; padding: 18px; }
    .internship-aside { display: flex; justify-content: space-between; align-items: center; border-right: 0; border-bottom: 1px solid var(--line); padding: 0 0 12px; }
    .internship-index { margin: 0; }
    .internship-content h2 { font-size: 16px; }
    .featured-repo { grid-template-columns: 1fr; gap: 22px; padding: 21px; }
    .featured-repo-visual { padding: 0 0 21px; border: 0; border-bottom: 1px solid var(--line); }
    .featured-repo-logo { width: 200px; height: 96px; margin-bottom: 17px; }
    .featured-repo-visual-actions { flex-direction: row; justify-content: center; flex-wrap: wrap; }
    .featured-repo-copy h3 { font-size: 19px; }
    .footer-shell { align-items: start; flex-direction: column; gap: 14px; }
    .site-footer { margin-top: 40px; }
}
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after { transition: none !important; animation: none !important; }
}
@media print {
    .drawing-frame, .site-header, .page-index, .filters, .database-toolbar, .skip-link { display: none; }
    .container { width: 100%; }
    .hero, .page-hero { padding-top: 0; }
    .card, .pub-item, .internship-card, .project-card, .book-card { break-inside: avoid; box-shadow: none; }
}