@font-face { font-family: "Manrope"; src: url("assets/fonts/manrope-latin-variable.woff2") format("woff2"); font-style: normal; font-weight: 400 800; font-display: swap; }
@font-face { font-family: "Instrument Serif"; src: url("assets/fonts/instrument-serif-latin.woff2") format("woff2"); font-style: normal; font-weight: 400; font-display: swap; }
@font-face { font-family: "Instrument Serif"; src: url("assets/fonts/instrument-serif-italic-latin.woff2") format("woff2"); font-style: italic; font-weight: 400; font-display: swap; }
:root {
  --palette-pink: #e91b63; --palette-blush: #efb4cf; --palette-yellow: #f9e975;
  --palette-lime: #92c43d; --palette-sky: #539ed4; --palette-navy: #222d82;
  --paper: #fafaf7; --white: #fff; --ink: #263449; --muted: #5d647d;
  --blue: var(--palette-navy); --accent: var(--palette-yellow); --line: #e3e8ef; --soft: #f1f6fb;
  --surface-sky: #e8f2fb; --surface-blush: #fae7f0; --surface-yellow: #fff7cf; --surface-lime: #edf5d8;
  --serif: "Instrument Serif", Georgia, "Times New Roman", serif;
  --sans: "Manrope", "Segoe UI", -apple-system, BlinkMacSystemFont, Arial, sans-serif;
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 92px; scrollbar-gutter: stable; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--sans); font-size: 16px; line-height: 1.7; -webkit-font-smoothing: antialiased; }
::selection { background: var(--accent); color: var(--ink); }
a { color: inherit; text-decoration: none; text-underline-offset: 5px; }
a:hover { text-decoration: underline; }
button { font: inherit; cursor: pointer; }
button, a { -webkit-tap-highlight-color: transparent; }
:focus-visible { outline: 3px solid var(--palette-pink); outline-offset: 5px; }
img { display: block; max-width: 100%; height: auto; }
h1, h2, h3, h4, p, figure { margin: 0; }
h1, h2, h3, h4 { color: var(--blue); line-height: 1.15; }
strong { font-weight: 700; }
[hidden] { display: none !important; }
.container { width: min(1248px, calc(100% - 112px)); margin-inline: auto; }
.skip-link { position: fixed; top: -90px; left: 20px; padding: 12px 22px; border-radius: 99px; background: var(--ink); color: white; z-index: 100; }
.skip-link:focus { top: 12px; }
.site-header { position: sticky; top: 0; z-index: 20; background: rgba(250,250,247,.97); border-bottom: 1px solid var(--line); }
.header-inner { display: flex; min-height: 76px; align-items: center; justify-content: space-between; gap: 28px; }
.brand { display: flex; align-items: center; gap: 10px; }
.wordmark { display: inline-flex; align-items: center; font-size: 16px; font-weight: 700; white-space: nowrap; letter-spacing: -.5px; }
.wordmark:hover { text-decoration: none; }
.buddy-button { position: relative; display: grid; place-items: center; flex-shrink: 0; width: 48px; height: 48px; padding: 0; border: 0; border-radius: 50%; background: transparent; color: var(--ink); touch-action: manipulation; }
.buddy-button:disabled { cursor: default; }
.buddy { display: block; width: 48px; height: 48px; overflow: visible; }
.buddy-body { transform-box: fill-box; transform-origin: center 80%; transform: rotate(var(--buddy-tilt, 0deg)); transition: transform .16s ease-out; }
.buddy-pupil { transform: translate(var(--buddy-x, 0px), var(--buddy-y, 0px)); transition: transform .12s ease-out; }
.buddy-eye { transform-box: fill-box; transform-origin: center; }
.buddy-hello { position: absolute; top: calc(100% - 3px); left: 50%; padding: 4px 11px; border: 1px solid var(--ink); border-radius: 99px; background: var(--palette-yellow); color: var(--ink); font-size: 11px; font-weight: 700; line-height: 1.5; pointer-events: none; opacity: 0; transform: translate(-50%, -4px) rotate(-7deg); transition: opacity .15s, transform .15s; }
.is-greeting .buddy-hello { opacity: 1; transform: translate(-50%, 3px) rotate(-7deg); }
.is-greeting .buddy-body { animation: buddy-bob .55s ease-out; }
.is-greeting .buddy-eye-right { animation: buddy-wink .75s ease; }
@keyframes buddy-bob { 0%, 100% { transform: translateY(0) rotate(0); } 40% { transform: translateY(-3px) rotate(-5deg); } 70% { transform: translateY(-1px) rotate(3deg); } }
@keyframes buddy-wink { 0%, 70%, 100% { transform: scaleY(1); } 25%, 50% { transform: scaleY(.08); } }
.click-laser { position: fixed; inset: 0; z-index: 50; display: block; width: 100%; height: 100%; overflow: hidden; pointer-events: none; visibility: hidden; opacity: 0; fill: none; stroke-linecap: round; }
.click-laser.is-active { visibility: visible; animation: laser-flash .46s ease-out both; }
.click-laser [data-laser-eye] path { stroke-dasharray: 1; stroke-dashoffset: 1; }
.click-laser.is-active [data-laser-eye] path { animation: laser-travel .46s ease-out both; }
.laser-glow { stroke: var(--palette-sky); stroke-width: 8; opacity: .2; }
.laser-beam { stroke: var(--palette-sky); stroke-width: 3; }
.laser-core { stroke: white; stroke-width: 1; }
.laser-ring, .laser-spark { stroke: var(--palette-sky); stroke-width: 1.5; }
.laser-dot { fill: var(--palette-yellow); }
.click-laser-impact { transform-box: fill-box; transform-origin: center; opacity: 0; }
.click-laser.is-active .click-laser-impact { animation: laser-impact .37s .08s ease-out both; }
@keyframes laser-travel { 0% { stroke-dashoffset: 1; } 25%, 100% { stroke-dashoffset: 0; } }
@keyframes laser-flash { 0% { opacity: 0; } 12%, 50% { opacity: 1; } 100% { opacity: 0; } }
@keyframes laser-impact { 0% { opacity: 0; transform: scale(.4); } 25% { opacity: 1; } 100% { opacity: 0; transform: scale(1.6); } }
nav { display: flex; align-items: center; gap: 3px; font-size: 12px; font-weight: 600; }
nav a { padding: 11px 12px; transition: color .2s; }
nav a:hover, nav a[aria-current="location"] { color: var(--blue); text-decoration: underline; text-decoration-color: var(--palette-sky); }
nav .nav-contact { display: inline-flex; align-items: center; gap: 12px; padding: 9px 14px; margin-left: 13px; border-radius: 8px; background: var(--palette-yellow); color: var(--blue); }
.nav-contact span { font-size: 17px; line-height: 1; }
nav .nav-contact:hover, nav .nav-contact[aria-current="location"] { background: #f1df62; text-decoration: none; }
.menu-toggle { display: none; align-items: center; gap: 18px; padding: 8px 16px; border: 1px solid var(--line); border-radius: 8px; background: transparent; color: var(--ink); font-size: 13px; }
.menu-toggle span { font-size: 20px; line-height: 1.4; }
.eyebrow { color: var(--muted); font-size: 11px; line-height: 1.6; letter-spacing: 1.4px; font-weight: 600; text-transform: uppercase; }
.hero { display: grid; grid-template-columns: minmax(0, 1fr) 224px; align-items: center; gap: 48px; padding-block: 40px; }
.hero-copy { min-width: 0; }
.korean-name { display: inline-block; margin-left: 16px; font-size: 14px; font-weight: 400; letter-spacing: .5px; color: var(--muted); }
h1 { margin-block: 10px 8px; font-size: 56px; line-height: 1.15; letter-spacing: -.05em; font-weight: 600; }
.hero-role { font-size: 16px; font-weight: 500; line-height: 1.7; }
.portrait-block { padding-bottom: 4px; }
.portrait-frame { display: block; overflow: hidden; border-radius: 12px; background: var(--soft); }
.portrait { width: 100%; aspect-ratio: 3 / 4; object-fit: cover; }
.portrait-block figcaption { margin-top: 10px; color: var(--muted); font-size: 10px; line-height: 1.6; }
.portrait-flip { position: relative; width: 100%; aspect-ratio: 3 / 4; padding: 0; border: 0; overflow: visible; background: transparent; color: inherit; perspective: 1000px; touch-action: manipulation; }
.portrait-flip:disabled { cursor: default; }
.portrait-card { position: absolute; inset: 0; display: block; border-radius: inherit; transform-style: preserve-3d; transition: transform .65s cubic-bezier(.2,.65,.3,1); }
.portrait-face { position: absolute; inset: 0; display: block; overflow: hidden; border-radius: inherit; background: var(--soft); -webkit-backface-visibility: hidden; backface-visibility: hidden; }
.portrait-face .portrait { height: 100%; }
.portrait-back { transform: rotateY(180deg); }
.portrait-flip[aria-pressed="true"] .portrait-card { transform: rotateY(180deg); }
.intro, .affiliation { max-width: 640px; color: var(--muted); font-size: 15px; line-height: 1.85; }
.intro { margin-top: 14px; }
.affiliation { margin-top: 5px; font-size: 13px; }
.affiliation a, .timeline a { text-decoration: underline; text-decoration-color: var(--palette-sky); }
.hero-actions { display: flex; align-items: center; flex-wrap: wrap; gap: 18px 26px; margin-top: 18px; }
.button { display: inline-flex; align-items: center; justify-content: space-between; gap: 18px; min-height: 44px; padding: 11px 18px; border: 1px solid var(--blue); border-radius: 8px; font-size: 13px; font-weight: 600; line-height: 1.5; transition: background .2s, color .2s; }
.button > span { flex-shrink: 0; font-size: 19px; font-weight: 400; line-height: 1; }
.button-primary { color: var(--blue); background: transparent; }
.button:hover, .button:focus-visible { color: var(--blue); background: var(--soft); text-decoration: none; }
.text-link { display: inline-flex; align-items: center; gap: 12px; font-size: 12px; font-weight: 600; line-height: 1.5; }
.text-link > span { flex-shrink: 0; font-size: 17px; font-weight: 400; line-height: 1; }
.text-link:hover { color: var(--blue); text-decoration: underline; text-decoration-color: var(--palette-sky); }
.research-tags { display: flex; flex-wrap: wrap; gap: 6px 18px; margin-top: 16px; color: var(--muted); font-size: 11px; }
.research-tags span { display: inline-flex; align-items: center; gap: 7px; }
.research-tags span::before { content: ""; width: 6px; height: 6px; flex-shrink: 0; border-radius: 50%; background: var(--palette-sky); }
.research-tags span:nth-child(2)::before { background: var(--palette-pink); }
.research-tags span:nth-child(3)::before { background: var(--palette-lime); }
.section { padding-block: 56px; }
#research { padding-top: 32px; border-top: 1px solid var(--line); }
#about { padding-bottom: 28px; }
#publications { --section-accent: var(--palette-pink); }
#about { --section-accent: var(--palette-lime); }
#projects { --section-accent: var(--palette-yellow); }
.projects-section { padding-top: 28px; border-top: 1px solid var(--line); }
.projects-section > .section-heading { margin-bottom: 20px; }
.projects-section > .research-projects { margin-top: 0; }
.section-heading { display: flex; align-items: flex-end; justify-content: space-between; gap: 24px; margin-bottom: 28px; }
.section-heading h2 { padding-left: 12px; border-left: 4px solid var(--section-accent, var(--palette-sky)); }
h2 { font-size: 32px; letter-spacing: -.035em; font-weight: 600; line-height: 1.2; }
.research-feature { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); gap: 18px 28px; padding-block: 24px; border-bottom: 1px solid var(--line); }
.research-feature:first-of-type { padding-top: 0; }
.research-image { display: flex; align-items: center; justify-content: center; min-width: 0; }
.research-image img { width: 100%; height: auto; background: white; border-radius: 4px; }
.research-description { display: flex; flex-direction: column; align-items: flex-start; min-width: 0; }
.project-meta { display: flex; align-items: center; justify-content: space-between; gap: 16px; width: 100%; color: var(--muted); font-size: 10px; font-weight: 600; letter-spacing: .6px; text-transform: uppercase; margin-bottom: 14px; }
.research-description h3 { font-size: clamp(26px, 2.5vw, 30px); letter-spacing: -.035em; font-weight: 500; line-height: 1.2; }
.research-description > p { color: var(--muted); font-size: 13px; line-height: 1.85; margin-block: 12px; }
.topic-list { display: flex; flex-wrap: wrap; gap: 5px 16px; margin-bottom: 16px; }
.topic-list span { font-size: 11px; color: var(--muted); }
.research-description .text-link { margin-top: auto; }
.research-video { grid-column: 1 / -1; }
.research-video summary { display: flex; align-items: center; gap: 12px; min-height: 44px; padding-block: 8px; color: var(--ink); list-style: none; cursor: pointer; font-size: 13px; font-weight: 600; }
.research-video summary::-webkit-details-marker { display: none; }
.research-video summary:hover { color: var(--blue); }
.research-video summary:focus-visible { outline-offset: -5px; }
.video-play { color: var(--blue); font-size: 10px; }
.video-duration { color: var(--muted); font-size: 11px; font-weight: 400; }
.video-toggle { margin-left: auto; font-size: 23px; font-weight: 400; transition: transform .2s; }
.research-video[open] .video-toggle { transform: rotate(45deg); }
.video-frame { margin-block: 8px 0; }
.video-frame video { display: block; width: 100%; height: auto; aspect-ratio: 16 / 9; border-radius: 8px; background: #161c50; }
.video-link { margin-top: 12px; color: var(--muted); font-size: 11px; text-align: right; }
.video-link a { display: inline-block; padding-block: 5px; }
.video-link span { margin-left: 8px; }
.publications-section { border-top: 1px solid var(--line); }
.publication-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding-bottom: 16px; border-bottom: 1px solid var(--line); }
.filters { display: flex; flex-wrap: wrap; gap: 7px; }
.filter-button { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 40px; padding: 8px 14px; background: transparent; border: 1px solid var(--line); color: var(--muted); font-size: 12px; border-radius: 999px; transition: background .2s, border-color .2s, color .2s; }
.filter-button:hover { background: var(--soft); border-color: var(--palette-sky); color: var(--blue); }
.filter-button.is-active { background: transparent; border-color: var(--blue); color: var(--blue); font-weight: 600; }
.filter-button.is-active:hover { background: var(--soft); }
.filter-button span { display: inline-flex; align-items: center; justify-content: center; min-width: 22px; height: 22px; padding-inline: 6px; border-radius: 999px; background: var(--soft); color: var(--blue); font-size: 10px; font-weight: 700; line-height: 1; font-variant-numeric: tabular-nums; }
.filter-button.is-active span { background: var(--surface-sky); }
#publication-count { color: var(--muted); font-size: 11px; white-space: nowrap; }
.publication { display: grid; grid-template-columns: 64px minmax(0, 1fr); gap: 24px; padding-block: 20px; border-bottom: 1px solid var(--line); }
.publication:last-child { border-bottom: 0; padding-bottom: 0; }
.publication-year { color: var(--muted); font-size: 20px; line-height: 1.4; font-weight: 500; letter-spacing: -.5px; }
.venue { color: var(--muted); font-size: 10px; letter-spacing: .5px; line-height: 1.7; margin-bottom: 6px; text-transform: uppercase; }
.publication h3 { font-size: 20px; font-weight: 500; letter-spacing: -.55px; line-height: 1.45; max-width: 970px; text-wrap: pretty; }
.authors { font-size: 12px; color: var(--muted); margin-top: 8px; }
.authors strong { color: var(--ink); font-weight: 700; }
.paper-links { display: flex; flex-wrap: wrap; gap: 6px 20px; margin-top: 8px; font-size: 11px; font-weight: 600; }
.paper-links a { display: inline-flex; align-items: center; gap: 8px; min-height: 32px; padding-block: 4px; color: var(--blue); }
.paper-links a:hover { text-decoration: underline; text-decoration-color: var(--palette-sky); }
.paper-links span { font-size: 14px; }
.award-label { display: inline-block; background: var(--surface-lime); color: var(--blue); padding: 3px 8px; border-radius: 4px; margin-left: 9px; font-size: 10px; letter-spacing: 0; text-transform: none; vertical-align: middle; }
.background-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; }
.background-details { margin-top: 32px; align-items: start; }
.column-title { border-bottom: 1px solid var(--line); padding-bottom: 12px; font-size: 13px; font-weight: 600; letter-spacing: .3px; }
.awards-block .column-title { border-bottom-color: var(--palette-blush); }
.teaching-block .column-title { border-bottom-color: var(--palette-lime); }
.timeline { list-style: none; margin: 18px 0 0; padding: 0; }
.timeline li { position: relative; margin-left: 4px; padding: 0 0 20px 20px; border-left: 1px solid var(--line); }
.timeline li:last-child { padding-bottom: 0; }
.timeline li::before { content: ""; position: absolute; top: 6px; left: -4px; width: 7px; height: 7px; background: var(--palette-sky); border-radius: 50%; }
.date { color: var(--muted); font-size: 11px; line-height: 1.4; margin-bottom: 8px; }
.timeline h4 { font-size: 19px; font-weight: 500; line-height: 1.4; letter-spacing: -.4px; margin-bottom: 6px; }
.timeline li > p:not(.date) { font-size: 13px; }
.timeline .detail { color: var(--muted); line-height: 1.8; margin-top: 5px; }
.awards-block, .teaching-block { min-width: 0; }
.award-row { display: flex; align-items: center; gap: 20px; padding-block: 16px; border-bottom: 1px solid var(--line); }
.award-row > span:first-child { min-width: 52px; color: var(--muted); font-size: 12px; align-self: flex-start; padding-top: 2px; }
.award-row p { font-size: 14px; }
.award-row p span { display: block; color: var(--muted); font-size: 12px; margin-top: 5px; }
.award-demo-link { display: inline-flex; align-items: center; min-height: 32px; color: var(--blue); font-size: 11px; font-weight: 600; }
.research-projects, .independent-projects, .demo-gallery { margin-top: 32px; }
.demo-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 28px; margin-top: 20px; }
.demo-card { min-width: 0; }
.demo-card video { display: block; width: 100%; height: auto; aspect-ratio: 16 / 9; object-fit: contain; border-radius: 8px; background: #161c50; }
.demo-caption { padding-top: 14px; }
.demo-meta { color: var(--muted); font-size: 10px; line-height: 1.7; margin-bottom: 6px; }
.demo-card h4 { font-size: 22px; font-weight: 500; line-height: 1.4; letter-spacing: -.5px; }
.demo-description { margin-top: 6px; color: var(--muted); font-size: 13px; line-height: 1.8; }
.participating-projects { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; margin-top: 20px; }
.project-entry { padding-bottom: 20px; border-bottom: 1px solid var(--line); }
.project-entry h4 { font-size: 20px; font-weight: 500; line-height: 1.4; letter-spacing: -.4px; }
.project-entry .date { margin-bottom: 8px; }
.project-role { margin-top: 6px; color: var(--ink); font-size: 12px; }
.project-entry .detail { margin-top: 10px; color: var(--muted); font-size: 13px; line-height: 1.8; }
.funding-entry { display: grid; grid-template-columns: 85px minmax(0,1fr); gap: 24px; padding-block: 20px; border-bottom: 1px solid var(--line); }
.funding-year { align-self: start; justify-self: start; min-width: 75px; padding: 12px 8px; border-radius: 8px; background: var(--palette-yellow); color: var(--blue); font-size: 24px; line-height: 1.3; letter-spacing: -.5px; text-align: center; }
.funding-year span { display: block; margin-top: 9px; color: var(--muted); font: 10px var(--sans); letter-spacing: 0; }
.funding-program { font-size: 13px; font-weight: 700; line-height: 1.6; }
.funding-program span { display: block; color: var(--muted); font-size: 11px; font-weight: 400; margin-top: 4px; }
.funding-details h4 { font-size: 21px; font-weight: 500; line-height: 1.45; letter-spacing: -.5px; margin-top: 12px; overflow-wrap: anywhere; }
.funding-funder { color: var(--muted); font-size: 12px; margin-top: 10px; }
.product-project { display: grid; grid-template-columns: minmax(0,1fr) 30%; padding-block: 20px; border-bottom: 1px solid var(--line); }
.product-main { min-width: 0; padding-right: 28px; }
.product-heading { display: flex; align-items: center; gap: 16px; }
.product-icon { width: 64px; height: 64px; flex-shrink: 0; border-radius: 12px; }
.product-heading .eyebrow { font-size: 9px; letter-spacing: 1px; margin-bottom: 7px; }
.product-heading h4 { font-size: 30px; font-weight: 500; letter-spacing: -1px; }
.product-heading h4 span { display: inline-block; margin-left: 11px; color: var(--muted); font-size: 13px; font-weight: 400; letter-spacing: 0; }
.product-summary { color: var(--muted); font-size: 13px; line-height: 1.9; margin-top: 14px; max-width: 680px; }
.product-roles { display: flex; flex-wrap: wrap; gap: 6px 16px; list-style: none; margin: 12px 0 0; padding: 0; }
.product-roles li { color: var(--muted); font-size: 11px; }
.product-links { display: flex; align-items: center; flex-wrap: wrap; gap: 12px 24px; margin-top: 16px; }
.product-release { color: var(--muted); font-size: 10px; }
.product-impact { display: flex; align-items: center; justify-content: center; padding: 20px; border-radius: 12px; background: var(--blue); color: white; text-align: center; }
.product-impact strong { display: block; color: var(--palette-yellow); font-size: 42px; font-weight: 500; line-height: 1.1; letter-spacing: -.05em; }
.product-impact span { display: block; margin-top: 10px; color: white; font-size: 12px; }
.product-impact small { display: block; margin-top: 10px; font-size: 10px; color: #c7d4eb; }
.teaching-block .column-title { display: flex; justify-content: space-between; align-items: baseline; gap: 20px; }
.teaching-block .column-title span { color: var(--muted); font-size: 11px; font-weight: 400; letter-spacing: 0; }
.teaching-courses { margin: 0; padding: 0; list-style: none; }
.teaching-courses li { display: grid; grid-template-columns: 80px minmax(0, 1fr); align-items: baseline; gap: 16px; padding-block: 16px; border-bottom: 1px solid var(--line); }
.teaching-courses span { color: var(--muted); font-size: 11px; }
.teaching-courses strong { font-size: 15px; font-weight: 500; line-height: 1.5; letter-spacing: -.3px; }
.course-code { margin-top: 5px; color: var(--muted); font-size: 11px; line-height: 1.5; }
.skills-line { display: flex; align-items: baseline; flex-wrap: wrap; gap: 12px 28px; border-top: 1px solid var(--line); padding-top: 18px; margin-top: 28px; }
.skills-line p { font-size: 13px; color: var(--muted); }
.contact-section { border-top: 1px solid #d7e6f3; background: var(--surface-sky); }
.contact-inner { display: flex; align-items: flex-end; justify-content: space-between; gap: 40px; padding-block: 32px; }
.contact-email { display: inline-flex; align-items: center; gap: 16px; min-height: 44px; margin-top: 12px; color: var(--blue); font-size: 17px; }
.contact-email span { flex-shrink: 0; font-size: 20px; }
.contact-email:hover { text-decoration: underline; text-decoration-color: var(--palette-sky); }
.contact-links { min-width: 205px; display: flex; flex-direction: column; gap: 10px; padding-bottom: 4px; }
.contact-links a { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding-block: 6px; font-size: 12px; }
.contact-links a:hover { color: var(--blue); text-decoration: underline; text-decoration-color: var(--palette-sky); }
.contact-links span { font-size: 18px; line-height: 1; }
.site-footer { display: flex; justify-content: space-between; align-items: center; gap: 20px; padding-block: 18px; color: var(--muted); font-size: 10px; }
.site-footer a { padding-block: 8px; }
.site-footer a span { margin-left: 12px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
@media (max-width: 1100px) {
  .demo-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .container { width: calc(100% - 80px); }
  .hero { gap: 40px; }
  h1 { font-size: 50px; }
  .hero-actions { gap: 17px; }
  .background-grid { gap: 36px; }
  .contact-inner { gap: 28px; }
  .contact-links { min-width: 180px; }
}
@media (max-width: 780px) {
  html { scroll-padding-top: 84px; }
  .container { width: calc(100% - 48px); }
  .header-inner { min-height: 68px; flex-wrap: wrap; gap: 0; }
  .menu-toggle:not([hidden]) { display: inline-flex; }
  nav { width: 100%; flex-wrap: wrap; gap: 6px; padding-block: 3px 16px; }
  .js nav { display: none; }
  .js nav.is-open { display: flex; }
  nav .nav-contact { margin-left: 0; }
  .hero { grid-template-columns: minmax(0,1fr) 184px; gap: 28px; padding-block: 32px; }
  h1 { font-size: 46px; }
  .portrait-block { display: block; padding: 0; }
  .portrait-frame { width: 100%; }
  .portrait-block figcaption { margin-top: 13px; font-size: 10px; }
  .intro { max-width: 650px; }
  .korean-name { font-size: 13px; margin-left: 12px; }
  .hero-actions { gap: 22px; }
  .section { padding-block: 44px; }
  #about { padding-bottom: 24px; }
  .projects-section { padding-top: 24px; }
  .section-heading { gap: 20px; margin-bottom: 24px; }
  .research-feature { grid-template-columns: 1fr; gap: 18px; }
  .research-description h3 { font-size: 28px; }
  .research-description > p { max-width: 560px; }
  .project-meta { margin-bottom: 12px; }
  .publication { grid-template-columns: 64px minmax(0,1fr); gap: 18px; }
  .publication h3 { font-size: 18px; }
  .background-grid { gap: 28px; }
  .funding-entry { gap: 18px; grid-template-columns: 75px minmax(0,1fr); }
  .funding-details h4 { font-size: 21px; }
  .product-project { grid-template-columns: minmax(0,1fr) 27%; }
  .product-heading { gap: 16px; }
  .product-icon { width: 60px; height: 60px; }
  .product-heading h4 { font-size: 30px; }
  .product-impact { padding-inline: 15px; }
  .product-impact strong { font-size: clamp(30px, 4.6vw, 36px); }
  .background-details { grid-template-columns: 1fr; gap: 28px; }
  .contact-inner { flex-direction: column; align-items: stretch; padding-block: 32px; gap: 24px; }
  .contact-links { flex-direction: row; flex-wrap: wrap; gap: 8px; min-width: 0; }
  .contact-links a { gap: 12px; min-height: 40px; }
}
@media (max-width: 580px) {
  .container { width: calc(100% - 40px); }
  .wordmark { font-size: 14px; gap: 9px; }
  .header-inner { min-height: 64px; }
  nav { gap: 4px; font-size: 11px; }
  nav a { padding: 10px 13px; }
  nav .nav-contact { padding-left: 15px; gap: 12px; }
  h1 { font-size: clamp(36px, 10vw, 44px); }
  .hero { grid-template-columns: 1fr; gap: 22px; padding-block: 28px 32px; }
  .portrait-block { display: flex; align-items: center; }
  .portrait-frame { width: 144px; flex-shrink: 0; }
  .portrait-block { gap: 20px; }
  .portrait-block figcaption { margin: 0; font-size: 10px; }
  .intro { font-size: 14px; line-height: 1.85; }
  .affiliation { font-size: 12px; }
  .hero-actions { gap: 20px; }
  .section { padding-block: 36px; }
  .projects-section { padding-top: 24px; }
  #research { padding-top: 28px; }
  .section-heading { align-items: flex-start; flex-direction: column; gap: 18px; margin-bottom: 22px; }
  h2 { font-size: 28px; }
  .research-feature { padding-block: 20px; }
  .research-description h3 { font-size: 26px; }
  .research-description > p { font-size: 12px; }
  .project-meta { font-size: 9px; margin-bottom: 12px; }
  .publication-toolbar { align-items: flex-start; flex-direction: column; gap: 12px; padding-bottom: 14px; }
  .filter-button { padding-inline: 12px; }
  .publication { grid-template-columns: 1fr; gap: 8px; padding-block: 18px; }
  .publication-year { font-size: 18px; }
  .venue { font-size: 9px; }
  .publication h3 { font-size: 17px; line-height: 1.5; }
  .authors { font-size: 11px; line-height: 1.85; }
  .award-label { margin-left: 0; margin-top: 5px; margin-right: 5px; font-size: 9px; }
  .paper-links { margin-top: 10px; }
  .background-grid { grid-template-columns: 1fr; gap: 28px; }
  .timeline h4 { font-size: 18px; }
  .background-details { margin-top: 28px; }
  .award-row { gap: 18px; padding-block: 15px; }
  .award-row > span:first-child { min-width: 44px; font-size: 10px; }
  .award-row p { font-size: 12px; }
  .award-row p span { font-size: 10px; }
  .research-projects, .independent-projects, .demo-gallery { margin-top: 28px; }
  .demo-grid { grid-template-columns: 1fr; gap: 24px; margin-top: 16px; }
  .demo-description { font-size: 12px; }
  .demo-card .paper-links a, .award-demo-link { min-height: 44px; }
  .participating-projects { grid-template-columns: 1fr; gap: 14px; }
  .funding-entry { grid-template-columns: 1fr; gap: 16px; }
  .funding-year { display: flex; align-items: baseline; gap: 13px; }
  .funding-year span { margin-top: 0; }
  .funding-details h4 { font-size: 20px; }
  .funding-funder { font-size: 11px; }
  .product-project { grid-template-columns: 1fr; gap: 20px; }
  .product-main { padding-right: 0; }
  .product-heading { gap: 15px; }
  .product-heading h4 { font-size: 30px; }
  .product-heading h4 span { font-size: 11px; margin-left: 6px; }
  .product-heading .eyebrow { font-size: 8px; }
  .product-icon { width: 56px; height: 56px; }
  .product-summary { font-size: 12px; }
  .product-impact { padding: 18px; }
  .product-impact p { display: flex; align-items: baseline; justify-content: center; flex-wrap: wrap; gap: 14px; }
  .product-impact strong { font-size: clamp(30px, 4.6vw, 36px); }
  .product-impact span { margin-top: 0; }
  .product-impact small { flex-basis: 100%; margin-top: 0; }
  .teaching-courses li { grid-template-columns: 70px minmax(0, 1fr); gap: 12px; }
  .teaching-courses strong { font-size: 14px; }
  .skills-line { gap: 10px; margin-top: 24px; }
  .skills-line .eyebrow { width: 100%; }
  .skills-line p { font-size: 12px; }
  .contact-inner { padding-block: 28px; gap: 22px; }
  .contact-email { max-width: 100%; font-size: 15px; }
  .site-footer { flex-wrap: wrap; font-size: 9px; gap: 8px 20px; padding-block: 16px; }
  .site-footer > p:nth-child(2) { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .click-laser { display: none !important; }
  .buddy-body, .buddy-pupil { transform: none !important; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}
@media print {
  .site-header, .hero-actions, .research-tags, .publication-toolbar, .contact-section, .site-footer, .paper-links, .section-heading > a, .research-video, .demo-card video, .award-demo-link, .click-laser { display: none !important; }
  body { background: white; font-size: 11pt; }
  .container { width: 100%; }
  .hero { grid-template-columns: minmax(0,1fr) 110px; gap: 30px; padding-block: 10px 25px; }
  h1 { font-size: 30pt; }
  .portrait-frame { width: 100%; border-radius: 0; }
  .portrait-card { transform: none !important; }
  .portrait-back { display: none !important; }
  .section { padding-block: 30px; }
  #research { padding-top: 30px; }
  h2 { font-size: 27pt; }
  .section-heading { margin-bottom: 25px; }
  .publication, .research-feature, .timeline li, .award-row, .funding-entry, .product-project, .demo-card { break-inside: avoid; }
  .research-description { padding: 20px; }
  .research-description h3 { font-size: 20pt; }
  .research-image { min-height: 0; padding: 20px; }
  .publication { padding-block: 18px; }
  .publication[hidden] { display: grid !important; }
}