/* ==========================================================================
   Design tokens — white editorial
   ========================================================================== */
:root {
  --paper: #fdfdfb;
  --paper-tint: #f6f5f0;
  --ink: #1a2238;
  --ink-soft: #4a5168;
  --ink-dim: #8b8fa0;
  --hairline: rgba(26, 34, 56, 0.12);
  --hairline-soft: rgba(26, 34, 56, 0.07);
  --navy: #1e2c56;
  --gold: #b8860b;
  --gold-soft: rgba(184, 134, 11, 0.09);
  --radius: 4px;
  --serif: "Fraunces", "Noto Serif JP", Georgia, serif;
  --sans: "Inter", "Noto Sans JP", -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Sans", sans-serif;
  --maxw: 1120px;
  --maxw-wide: 1320px;
  --header-h: 72px;
}

* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html {
  scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 12px);
  -webkit-text-size-adjust: 100%; text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.85;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 28px; }
.container-wide { max-width: var(--maxw-wide); margin: 0 auto; padding: 0 28px; }

a { color: inherit; text-decoration: none; }
h1, h2, h3 { margin: 0; font-weight: 600; }
img { max-width: 100%; display: block; }

button {
  -webkit-appearance: none; appearance: none;
  font-family: inherit; color: inherit;
  border-radius: 0; margin: 0; padding: 0;
  background: none; border: none;
}

::selection { background: var(--navy); color: #fff; }
::-webkit-selection { background: var(--navy); color: #fff; }

:focus-visible { outline: 2px solid var(--gold); outline-offset: 3px; }

/* ---------- language switching ---------- */
html[data-lang="ja"] .en { display: none !important; }
html[data-lang="en"] .ja { display: none !important; }

/* ---------- scroll progress ---------- */
.progress-bar {
  position: fixed; top: 0; left: 0; height: 2px; width: 0%;
  background: var(--gold); z-index: 1000;
}

/* ==========================================================================
   Header
   ========================================================================== */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  height: var(--header-h);
  display: flex; align-items: center;
  background: rgba(253, 253, 251, 0.88);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}
.site-header.is-scrolled {
  border-bottom-color: var(--hairline-soft);
  box-shadow: 0 8px 24px rgba(26, 34, 56, 0.05);
}

.nav { display: flex; align-items: center; justify-content: space-between; width: 100%; gap: 1.5rem; }

.wordmark {
  font-family: var(--serif);
  font-size: 1.22rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.nav-links { display: flex; gap: 1.9rem; list-style: none; margin: 0; padding: 0; }
.nav-link {
  font-size: 0.85rem; font-weight: 500; letter-spacing: 0.04em;
  color: var(--ink-soft); position: relative; padding: 4px 0;
  transition: color 0.25s ease;
}
.nav-link::after {
  content: ""; position: absolute; left: 0; bottom: 0; height: 1px; width: 0%;
  background: var(--gold); transition: width 0.25s ease;
}
.nav-link:hover, .nav-link.is-current { color: var(--ink); }
.nav-link:hover::after, .nav-link.is-current::after { width: 100%; }

.nav-mobile-only { display: none; }

.lang-switch { display: flex; align-items: center; gap: 0.45rem; flex-shrink: 0; }
.lang-btn {
  background: none; border: none; padding: 2px 1px; cursor: pointer;
  font-family: var(--sans); font-size: 0.82rem; font-weight: 500;
  color: var(--ink-dim); letter-spacing: 0.03em;
  border-bottom: 1px solid transparent; transition: color 0.25s ease;
}
.lang-btn.is-active { color: var(--ink); border-bottom-color: var(--gold); }
.lang-btn:hover { color: var(--ink); }
.lang-sep { color: var(--hairline); font-size: 0.8rem; }

.nav-right { display: flex; align-items: center; gap: 1.2rem; flex-shrink: 0; }

.btn-mail {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.52rem 1.05rem; border-radius: var(--radius);
  background: var(--ink); color: #fff;
  font-size: 0.8rem; font-weight: 600; letter-spacing: 0.05em;
  transition: background 0.25s ease, transform 0.25s ease;
  white-space: nowrap;
}
.btn-mail:hover { background: var(--gold); transform: translateY(-1px); }
.btn-mail svg { width: 15px; height: 15px; flex-shrink: 0; }

.nav-toggle {
  display: none; flex-direction: column; justify-content: center; gap: 6px;
  width: 36px; height: 36px; background: none; border: none; cursor: pointer;
}
.nav-toggle span { width: 22px; height: 1.5px; background: var(--ink); transition: 0.3s ease; margin-left: auto; }
.nav-toggle span:first-child { width: 100%; }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  padding-top: calc(var(--header-h) + 4.5rem);
  padding-bottom: 5.5rem;
  border-bottom: 1px solid var(--hairline-soft);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.hero-kicker {
  font-size: 0.78rem; letter-spacing: 0.22em; text-transform: uppercase;
  color: var(--gold); font-weight: 600; margin: 0 0 1.6rem;
}

.hero-name {
  font-family: var(--serif);
  font-size: clamp(3.2rem, 7vw, 5.4rem);
  font-weight: 500;
  line-height: 1.02;
  letter-spacing: -0.015em;
  margin-bottom: 0.9rem;
}

.hero-name-jp {
  font-size: 1.02rem; color: var(--ink-dim); letter-spacing: 0.22em;
  margin: 0 0 2rem;
}

.hero-role { font-size: 1rem; color: var(--ink-soft); margin: 0 0 1.6rem; line-height: 2; }
.hero-role a { border-bottom: 1px solid var(--hairline); transition: border-color 0.25s; }
.hero-role a:hover { border-color: var(--gold); }

.hero-tagline { max-width: 30rem; color: var(--ink-soft); font-size: 0.98rem; margin: 0 0 2.4rem; }

.hero-actions { display: flex; gap: 0.9rem; flex-wrap: wrap; margin-bottom: 2.4rem; }

.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.78rem 1.7rem; font-size: 0.86rem; font-weight: 600;
  letter-spacing: 0.05em; border-radius: var(--radius);
  transition: all 0.28s ease; cursor: pointer; border: 1px solid var(--ink);
}
.btn-solid { background: var(--ink); color: var(--paper); }
.btn-solid:hover { background: var(--navy); border-color: var(--navy); transform: translateY(-2px); box-shadow: 0 12px 28px rgba(26, 34, 56, 0.22); }
.btn-line { background: transparent; color: var(--ink); }
.btn-line:hover { background: var(--ink); color: var(--paper); transform: translateY(-2px); box-shadow: 0 12px 28px rgba(26, 34, 56, 0.16); }
.btn-gold { background: var(--gold); border-color: var(--gold); color: #fff; }
.btn-gold:hover { background: #9a7009; border-color: #9a7009; transform: translateY(-2px); box-shadow: 0 12px 28px rgba(184, 134, 11, 0.3); }
.btn svg { width: 16px; height: 16px; flex-shrink: 0; }

.hero-mail { margin: -1.4rem 0 2.2rem; font-size: 0.92rem; }
.hero-mail a {
  color: var(--ink-soft); font-weight: 500; letter-spacing: 0.03em;
  border-bottom: 1px solid var(--hairline); padding-bottom: 1px;
  transition: color 0.25s ease, border-color 0.25s ease;
}
.hero-mail a:hover { color: var(--gold); border-color: var(--gold); }

.hero-affil { display: flex; align-items: center; gap: 1.8rem; margin: 0 0 1.9rem; }
.hero-affil img { display: block; }
.hero-affil-fujitsu { height: 22px; width: auto; }
.hero-affil-riken { display: inline-flex; align-items: center; gap: 0.5rem; }
.hero-affil-riken img { height: 26px; width: auto; }
.hero-affil-riken span {
  font-size: 0.82rem; font-weight: 600; letter-spacing: 0.08em; color: var(--ink-soft);
}
.hero-affil a { opacity: 0.85; transition: opacity 0.25s ease; }
.hero-affil a:hover { opacity: 1; }

.hero-socials { display: flex; gap: 1.5rem; flex-wrap: wrap; }
.hero-socials a {
  font-size: 0.8rem; font-weight: 500; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-dim); border-bottom: 1px solid transparent; padding-bottom: 2px;
  transition: color 0.25s ease, border-color 0.25s ease;
}
.hero-socials a:hover { color: var(--gold); border-color: var(--gold); }

.hero-art { margin: 0; }
.hero-art img { width: 100%; height: auto; }
.hero-art figcaption,
.research-banner figcaption,
.sw-art figcaption {
  margin-top: 0.9rem; font-size: 0.78rem; color: var(--ink-dim);
  letter-spacing: 0.04em; text-align: center;
}

/* ==========================================================================
   Sections
   ========================================================================== */
.section { padding: 6.5rem 0; }
.section-tinted { background: var(--paper-tint); }

.section-head {
  display: flex; align-items: baseline; gap: 1.4rem;
  margin-bottom: 3.2rem; padding-bottom: 1.4rem;
  border-bottom: 1px solid var(--hairline);
}
.section-no {
  font-family: var(--serif); font-style: italic; font-size: 1rem; color: var(--gold);
}
.section-title {
  font-family: var(--serif); font-size: clamp(1.9rem, 4vw, 2.7rem);
  font-weight: 500; letter-spacing: -0.01em;
}

/* reveal */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.is-visible { opacity: 1; transform: translateY(0); }

/* ==========================================================================
   About
   ========================================================================== */
.about-grid { display: grid; grid-template-columns: 1.55fr 1fr; gap: 4rem; align-items: start; }
.about-text p { margin: 0 0 1.4rem; color: var(--ink-soft); }
.about-text p strong { color: var(--ink); }

.about-callout {
  margin-top: 2rem; padding: 1.5rem 1.7rem;
  background: var(--gold-soft); border-left: 2px solid var(--gold);
  box-shadow: 0 10px 28px rgba(184, 134, 11, 0.07);
}
.about-callout p { margin: 0; font-size: 0.93rem; color: var(--ink); }
.about-callout strong { color: var(--gold); letter-spacing: 0.06em; }

.about-facts dl { margin: 0; display: flex; flex-direction: column; }
.about-facts dl > div {
  padding: 1.05rem 0; border-bottom: 1px solid var(--hairline-soft);
  display: grid; grid-template-columns: 92px 1fr; gap: 1rem;
}
.about-facts dl > div:first-child { border-top: 1px solid var(--hairline); }
.about-facts dt {
  font-size: 0.72rem; letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--ink-dim); padding-top: 3px;
}
.about-facts dd { margin: 0; font-size: 0.92rem; line-height: 1.65; }
.about-facts .muted { color: var(--ink-dim); font-size: 0.84rem; }
.about-facts a { border-bottom: 1px solid var(--hairline); }
.about-facts a:hover { border-color: var(--gold); color: var(--gold); }
.aff-logo { display: block; margin-bottom: 0.45rem; }
.aff-logo-fujitsu { height: 17px; width: auto; }
.aff-logo-riken { height: 22px; width: auto; }

/* ==========================================================================
   Research
   ========================================================================== */
.research-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0; border-top: 1px solid var(--hairline); }
.research-card {
  padding: 2.2rem 2rem 2.2rem 0;
  border-bottom: 1px solid var(--hairline);
  position: relative;
  transition: background 0.3s ease;
}
.research-card:hover { background: var(--gold-soft); }
.research-card:nth-child(odd) { border-right: 1px solid var(--hairline); padding-right: 2.4rem; }
.research-card:nth-child(even) { padding-left: 2.4rem; }
.research-index {
  font-family: var(--serif); font-style: italic; font-size: 0.95rem; color: var(--gold);
  display: block; margin-bottom: 0.9rem;
}
.research-card h3 { font-family: var(--serif); font-size: 1.32rem; font-weight: 500; margin-bottom: 0.7rem; }
.research-card p { margin: 0; color: var(--ink-soft); font-size: 0.92rem; }

.research-banner { margin: 4rem 0 0; }
.research-banner img { width: 100%; height: auto; }

/* ==========================================================================
   Publications
   ========================================================================== */
.year-filter { display: flex; gap: 0.5rem; flex-wrap: wrap; margin-bottom: 3rem; }
.chip {
  padding: 0.45rem 1.15rem; border: 1px solid var(--hairline);
  background: transparent; color: var(--ink-soft);
  font-family: var(--sans); font-size: 0.82rem; font-weight: 500; letter-spacing: 0.04em;
  cursor: pointer; transition: all 0.25s ease; border-radius: var(--radius);
}
.chip:hover { border-color: var(--ink); color: var(--ink); }
.chip.is-active { background: var(--ink); color: var(--paper); border-color: var(--ink); }

.pub-list { display: flex; flex-direction: column; border-top: 1px solid var(--hairline); }
.pub-item {
  display: grid; grid-template-columns: 86px 1fr; gap: 1.8rem;
  padding: 2rem 0; border-bottom: 1px solid var(--hairline-soft);
}
.pub-item.is-hidden { display: none; }
.pub-year {
  font-family: var(--serif); font-style: italic; font-size: 1.05rem; color: var(--ink-dim);
  padding-top: 3px;
}
.pub-title { font-family: var(--serif); font-size: 1.18rem; font-weight: 500; line-height: 1.55; margin-bottom: 0.55rem; }
.pub-authors { color: var(--ink-soft); font-size: 0.88rem; margin: 0 0 0.25rem; }
.pub-authors strong { color: var(--ink); font-weight: 600; }
.pub-venue { color: var(--ink-dim); font-size: 0.83rem; font-style: italic; margin: 0 0 0.7rem; }
.pub-desc { color: var(--ink-soft); font-size: 0.9rem; margin: 0 0 0.8rem; max-width: 46rem; }
.badge {
  display: inline-block; padding: 0.16rem 0.65rem; margin-left: 0.4rem;
  background: var(--gold-soft); color: var(--gold); border: 1px solid rgba(184, 134, 11, 0.28);
  font-style: normal; font-size: 0.68rem; font-weight: 700; letter-spacing: 0.06em;
  border-radius: 2px; vertical-align: 1px;
}
.pub-links { display: flex; gap: 1.3rem; }
.pub-links a {
  font-size: 0.8rem; font-weight: 600; letter-spacing: 0.05em; text-transform: uppercase;
  color: var(--gold); border-bottom: 1px solid transparent; padding-bottom: 1px;
  transition: border-color 0.25s;
}
.pub-links a:hover { border-color: var(--gold); }

/* ==========================================================================
   Software (top-page cards)
   ========================================================================== */
.software-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.6rem; }
.software-card {
  display: flex; flex-direction: column; position: relative;
  padding: 2.1rem 1.9rem; background: var(--paper);
  border: 1px solid var(--hairline); overflow: hidden;
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}
.software-card::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 2px;
  background: var(--gold); transform: scaleX(0); transform-origin: left;
  transition: transform 0.35s ease;
}
.software-card:hover {
  transform: translateY(-5px);
  border-color: var(--ink);
  box-shadow: 0 18px 44px rgba(26, 34, 56, 0.08);
}
.software-card:hover::before { transform: scaleX(1); }
.software-tag {
  font-size: 0.68rem; letter-spacing: 0.16em; text-transform: uppercase;
  color: var(--gold); font-weight: 700; margin-bottom: 1rem; display: inline-block;
}
.software-card h3 { font-family: var(--serif); font-size: 1.5rem; font-weight: 500; margin-bottom: 0.8rem; }
.software-card p { color: var(--ink-soft); font-size: 0.89rem; margin: 0 0 1.6rem; flex-grow: 1; }
.software-more { font-size: 0.8rem; font-weight: 600; letter-spacing: 0.05em; color: var(--ink); }

/* ==========================================================================
   Software detail page
   ========================================================================== */
.page-hero {
  padding-top: calc(var(--header-h) + 4.5rem);
  padding-bottom: 4rem;
  border-bottom: 1px solid var(--hairline-soft);
}
.page-title {
  font-family: var(--serif); font-size: clamp(2.8rem, 6vw, 4.4rem);
  font-weight: 500; line-height: 1.05; margin-bottom: 1.4rem;
}
.page-lead { max-width: 44rem; color: var(--ink-soft); font-size: 1rem; margin: 0; }

.software-detail .sw-grid {
  display: grid; grid-template-columns: 1.25fr 1fr; gap: 4rem; align-items: center;
}
.software-detail .sw-grid-flip { grid-template-columns: 1.25fr 1fr; }

.sw-name { font-family: var(--serif); font-size: clamp(2rem, 4vw, 2.9rem); font-weight: 500; margin: 0.4rem 0 0.3rem; }
.sw-sub { color: var(--ink-dim); font-size: 0.9rem; letter-spacing: 0.05em; margin: 0 0 1.6rem; }
.sw-desc { color: var(--ink-soft); font-size: 0.95rem; margin: 0 0 1.8rem; }

.sw-code {
  background: var(--ink); border-radius: var(--radius);
  padding: 1.2rem 1.4rem; margin-bottom: 1.8rem; overflow-x: auto;
}
.sw-code pre { margin: 0; }
.sw-code code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 0.82rem; line-height: 1.7; color: #e8ecf8; white-space: pre;
}

.sw-features { list-style: none; margin: 0 0 2.2rem; padding: 0; }
.sw-features li {
  position: relative; padding: 0.5rem 0 0.5rem 1.6rem;
  color: var(--ink-soft); font-size: 0.9rem;
  border-bottom: 1px solid var(--hairline-soft);
}
.sw-features li::before {
  content: "—"; position: absolute; left: 0; color: var(--gold);
}

.sw-links { display: flex; gap: 0.8rem; flex-wrap: wrap; }
.sw-art { margin: 0; }
.sw-art img { width: 100%; height: auto; }
.sw-diagram img { border: 1px solid var(--hairline); background: var(--paper); }

.back-home { padding-top: 2rem; }

/* ==========================================================================
   Talks (timeline)
   ========================================================================== */
.timeline-year {
  font-family: var(--serif); font-style: italic; font-size: 1.5rem; color: var(--gold);
  margin: 2.6rem 0 1rem;
}
.timeline > .timeline-year:first-child { margin-top: 0; }
.timeline-list { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--hairline); }
.timeline-list li {
  padding: 1.05rem 0.2rem; border-bottom: 1px solid var(--hairline-soft);
  color: var(--ink-soft); font-size: 0.92rem;
}
.t-date {
  display: inline-block; min-width: 84px; color: var(--ink);
  font-weight: 600; font-size: 0.82rem; letter-spacing: 0.04em; margin-right: 0.7rem;
}

/* ==========================================================================
   Awards
   ========================================================================== */
.award-list { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--hairline); }
.award-item {
  display: grid; grid-template-columns: 110px 1fr; gap: 1.6rem; align-items: start;
  padding: 1.7rem 0.2rem; border-bottom: 1px solid var(--hairline-soft);
}
.award-date { font-weight: 600; color: var(--gold); font-size: 0.85rem; letter-spacing: 0.04em; padding-top: 3px; }
.award-item h3 { font-family: var(--serif); font-size: 1.12rem; font-weight: 500; margin-bottom: 0.35rem; }
.award-item p { color: var(--ink-soft); font-size: 0.88rem; margin: 0; }

/* ==========================================================================
   Press
   ========================================================================== */
.press-list { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--hairline); }
.press-item {
  display: grid; grid-template-columns: 110px 1fr; gap: 1.6rem; align-items: start;
  padding: 1.5rem 0.2rem; border-bottom: 1px solid var(--hairline-soft);
}
.p-date { color: var(--gold); font-weight: 600; font-size: 0.85rem; letter-spacing: 0.04em; padding-top: 3px; }
.p-body { min-width: 0; }
.p-title { margin: 0; font-size: 0.95rem; color: var(--ink); line-height: 1.75; }
.p-title a { border-bottom: 1px solid var(--hairline); transition: border-color 0.25s, color 0.25s; }
.p-title a:hover { color: var(--gold); border-color: var(--gold); }

.press-sub { list-style: none; margin: 0.8rem 0 0; padding: 0 0 0 1.3rem; }
.press-sub li {
  position: relative; padding: 0.3rem 0;
  color: var(--ink-soft); font-size: 0.85rem;
}
.press-sub li::before { content: "·"; position: absolute; left: -1.1rem; color: var(--gold); font-weight: 700; }
.press-sub a { border-bottom: 1px solid var(--hairline-soft); transition: border-color 0.25s, color 0.25s; }
.press-sub a:hover { color: var(--gold); border-color: var(--gold); }

/* ==========================================================================
   Contact
   ========================================================================== */
.section-contact { border-top: 1px solid var(--hairline-soft); }
.contact-lead { max-width: 40rem; color: var(--ink-soft); margin: 0 0 2.8rem; font-size: 1rem; }

.contact-grid { display: flex; gap: 1.4rem; flex-wrap: wrap; margin-bottom: 2.8rem; }
.contact-card {
  display: flex; flex-direction: column; gap: 0.4rem;
  padding: 1.5rem 2rem; border: 1px solid var(--hairline); min-width: 280px;
  background: var(--paper);
  transition: all 0.28s ease;
}
.contact-card:hover { border-color: var(--ink); transform: translateY(-3px); box-shadow: 0 14px 34px rgba(26, 34, 56, 0.09); }
.contact-label { font-size: 0.7rem; letter-spacing: 0.14em; text-transform: uppercase; color: var(--ink-dim); }
.contact-value { font-size: 1rem; font-weight: 600; color: var(--ink); }

.contact-links { display: flex; gap: 1.6rem; flex-wrap: wrap; }
.contact-links a {
  font-size: 0.8rem; font-weight: 500; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-dim); border-bottom: 1px solid transparent; padding-bottom: 2px;
  transition: color 0.25s, border-color 0.25s;
}
.contact-links a:hover { color: var(--gold); border-color: var(--gold); }

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer { border-top: 1px solid var(--hairline); padding: 2.2rem 0; }
.footer-inner { display: flex; justify-content: space-between; align-items: center; }
.footer-inner p { margin: 0; color: var(--ink-dim); font-size: 0.82rem; letter-spacing: 0.04em; }
.back-to-top {
  width: 40px; height: 40px; border: 1px solid var(--hairline);
  background: transparent; color: var(--ink); cursor: pointer; font-size: 0.95rem;
  border-radius: var(--radius); transition: all 0.28s ease;
}
.back-to-top:hover { background: var(--ink); color: var(--paper); border-color: var(--ink); }

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width: 1060px) {
  .nav-links { gap: 1.3rem; }
  .hero-grid { gap: 2.5rem; }
}

@media (max-width: 920px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-art { max-width: 640px; margin: 0 auto; }
  .about-grid { grid-template-columns: 1fr; gap: 2.6rem; }
  .software-grid { grid-template-columns: 1fr; }
  .software-detail .sw-grid,
  .software-detail .sw-grid-flip { grid-template-columns: 1fr; gap: 2.4rem; }
  .sw-art { max-width: 560px; margin: 0 auto; }
}

@media (max-width: 820px) {
  .nav-right { display: none; }
  .nav-links {
    position: fixed; top: var(--header-h); left: 0; right: 0; bottom: 0;
    background: var(--paper); flex-direction: column; align-items: stretch;
    padding: 2rem 28px 2.4rem; gap: 1.3rem; overflow-y: auto;
    transform: translateX(100%); transition: transform 0.35s ease; z-index: 90;
    border-top: 1px solid var(--hairline-soft);
  }
  .nav-links.is-open { transform: translateX(0); }
  .nav-link { font-size: 1.05rem; }
  .nav-toggle { display: flex; }
  .nav-toggle.is-open span:nth-child(1) { transform: translateY(4px) rotate(45deg); }
  .nav-toggle.is-open span:nth-child(2) { width: 100%; transform: translateY(-3.5px) rotate(-45deg); }

  .nav-mobile-only { display: block; }
  .nav-mobile-only .lang-switch {
    justify-content: center; gap: 0.6rem; padding-bottom: 1.1rem;
    border-bottom: 1px solid var(--hairline-soft);
  }
  .nav-mobile-only .lang-btn { font-size: 0.95rem; }
  .nav-mobile-only .btn-mail {
    justify-content: center; width: 100%; padding: 0.85rem 1rem;
  }
  .nav-mobile-only .btn-mail-label { display: inline; }
}

@media (max-width: 640px) {
  .section { padding: 4.5rem 0; }
  .research-grid { grid-template-columns: 1fr; }
  .research-card:nth-child(odd) { border-right: none; padding-right: 0; }
  .research-card:nth-child(even) { padding-left: 0; }
  .pub-item { grid-template-columns: 1fr; gap: 0.4rem; }
  .award-item, .press-item { grid-template-columns: 1fr; gap: 0.4rem; }
  .contact-card { min-width: 100%; }
}