/* 1. Design tokens --------------------------------------------------------- */
:root {
  color-scheme: light;
  --color-bg: #fafbf9;
  --color-surface: #ffffff;
  --color-soft: #f0f3f2;
  --color-ink: #182d3b;
  --color-muted: #596974;
  --color-accent: #284c63;
  --color-line: #dce3e5;
  --color-dark: #192f3e;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: clamp(1.5rem, 2.5vw, 2rem);
  --text-heading: clamp(2rem, 4vw, 3rem);
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4rem;
  --space-9: 6rem;
  --space-10: 8rem;
  --radius-sm: 4px;
  --radius-md: 8px;
  --page-width: 1180px;
  --page-gutter: clamp(1.25rem, 4.5vw, 4rem);
  --motion-fast: 180ms;
  --motion-enter: 420ms;
}

/* 2. Base and accessibility ------------------------------------------------ */
*,
*::before,
*::after { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 7rem; }
body { margin: 0; background: var(--color-bg); color: var(--color-ink); font-family: var(--font-sans); font-size: var(--text-base); line-height: 1.65; -webkit-font-smoothing: antialiased; }
::selection { background: #dce8ed; color: var(--color-ink); }
h1, h2, h3, p, figure { margin: 0; }
h1, h2, h3 { font-weight: 550; line-height: 1.15; letter-spacing: -0.035em; }
h1 { font-size: clamp(3rem, 6.4vw, 5.5rem); }
h2 { font-size: var(--text-heading); }
h3 { font-size: var(--text-xl); }
p { color: var(--color-muted); }
a { color: inherit; text-underline-offset: 0.25em; }
button { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
img, svg { display: block; max-width: 100%; }
img { height: auto; }
ul, ol { margin: 0; padding: 0; }
[hidden] { display: none !important; }
:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 5px; border-radius: var(--radius-sm); }
section[id], article[id] { scroll-margin-top: 2rem; }
.skip-link { position: fixed; z-index: 20; top: var(--space-3); left: var(--space-4); padding: var(--space-3) var(--space-5); background: var(--color-ink); color: white; transform: translateY(-160%); }
.skip-link:focus { transform: translateY(0); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }

/* 3. Shared layout and typography ----------------------------------------- */
.container { width: min(var(--page-width), calc(100% - var(--page-gutter) * 2)); margin-inline: auto; }
.section { padding-block: var(--space-9); border-top: 1px solid var(--color-line); }
.section-soft { background: var(--color-soft); }
.eyebrow, .section-number, .meta-label { font-family: var(--font-mono); font-size: var(--text-xs); font-weight: 400; letter-spacing: 0.09em; line-height: 1.5; text-transform: uppercase; }
.eyebrow { color: var(--color-accent); }
.eyebrow::before { content: ""; display: inline-block; width: 6px; height: 6px; margin-right: var(--space-3); background: currentColor; vertical-align: 2px; }
.section-number { color: var(--color-muted); margin-bottom: var(--space-5); }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: var(--space-6); margin-bottom: var(--space-7); }
.section-heading p:not(.section-number) { max-width: 34rem; margin-top: var(--space-4); }
.text-link { display: inline-flex; align-items: center; gap: var(--space-3); padding-block: var(--space-3); font-size: var(--text-sm); font-weight: 550; text-decoration: none; }
.text-link span[aria-hidden] { transition: transform var(--motion-fast) ease; }
.text-link:hover { color: var(--color-accent); }
.text-link:hover span[aria-hidden] { transform: translate(3px, -1px); }
.actions { display: flex; flex-wrap: wrap; gap: var(--space-3); }
.button { display: inline-flex; min-height: 48px; align-items: center; justify-content: center; gap: var(--space-5); padding: var(--space-3) var(--space-5); border: 1px solid var(--color-ink); border-radius: var(--radius-sm); background: var(--color-ink); color: white; font-size: var(--text-sm); font-weight: 550; text-decoration: none; transition: background var(--motion-fast) ease, border-color var(--motion-fast) ease, transform var(--motion-fast) ease; }
.button:hover { background: var(--color-accent); border-color: var(--color-accent); transform: translateY(-2px); }
.button.secondary { background: transparent; color: var(--color-ink); border-color: #c5d0d5; }
.button.secondary:hover { background: var(--color-soft); border-color: var(--color-accent); }
.placeholder-note { font-size: var(--text-sm); color: var(--color-muted); }
.placeholder-badge { display: inline-block; padding: var(--space-1) var(--space-2); border: 1px solid var(--color-line); border-radius: var(--radius-sm); color: var(--color-muted); font-family: var(--font-mono); font-size: 0.6875rem; line-height: 1.4; }
.prose { max-width: 43rem; }
.prose > * + * { margin-top: var(--space-5); }
.prose h3 { margin-top: var(--space-7); }
.lead { font-size: var(--text-lg); line-height: 1.75; }

/* 4. Header and navigation ------------------------------------------------ */
.site-header { position: sticky; z-index: 10; top: 0; background: var(--color-bg); border-bottom: 1px solid var(--color-line); }
.header-inner { min-height: 86px; display: flex; align-items: center; justify-content: space-between; gap: var(--space-6); }
.brand { display: inline-flex; align-items: center; gap: var(--space-3); flex-shrink: 0; text-decoration: none; }
.brand-mark { display: grid; place-items: center; width: 36px; height: 36px; border: 1px solid var(--color-ink); border-radius: 2px; font-size: 0.875rem; font-weight: 600; letter-spacing: -0.08em; }
.brand-name { font-size: var(--text-sm); font-weight: 550; letter-spacing: -0.025em; }
.site-nav { display: flex; align-items: center; gap: var(--space-6); }
.nav-list { list-style: none; display: flex; align-items: center; gap: var(--space-5); }
.nav-list a { display: inline-flex; align-items: center; min-height: 44px; font-size: var(--text-sm); text-decoration: none; color: var(--color-muted); transition: color var(--motion-fast) ease; }
.nav-list a:hover, .nav-list a[aria-current="page"] { color: var(--color-ink); }
.nav-list a[aria-current="page"] { text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 7px; }
.nav-social { padding-left: var(--space-6); border-left: 1px solid var(--color-line); }
.unavailable { display: inline-flex; align-items: center; gap: 5px; color: var(--color-muted); font-size: var(--text-sm); }
.unavailable small { font-family: var(--font-mono); font-size: 0.625rem; letter-spacing: 0; text-transform: uppercase; }
.nav-toggle { display: none; align-items: center; gap: var(--space-3); min-height: 44px; padding: var(--space-2) var(--space-3); border: 1px solid var(--color-line); border-radius: var(--radius-sm); background: transparent; color: var(--color-ink); font-size: var(--text-sm); cursor: pointer; }
.menu-icon { display: grid; gap: 5px; width: 16px; }
.menu-icon::before, .menu-icon::after { content: ""; width: 16px; height: 1px; background: currentColor; transition: transform var(--motion-fast) ease; }
.is-open .menu-icon::before { transform: translateY(3px) rotate(45deg); }
.is-open .menu-icon::after { transform: translateY(-3px) rotate(-45deg); }

/* 5. Home hero ------------------------------------------------------------ */
.hero { position: relative; overflow: hidden; }
.hero-inner { display: grid; grid-template-columns: 1.2fr 1fr; align-items: center; gap: var(--space-5); min-height: 645px; padding-block: var(--space-8); }
.hero-copy { position: relative; z-index: 1; }
.hero .eyebrow { margin-bottom: var(--space-6); }
.hero h1 { margin-bottom: var(--space-5); }
.hero-role { max-width: 31rem; font-size: var(--text-lg); }
.hero-role strong { font-weight: 550; color: var(--color-ink); }
.hero-focus { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-3); margin-top: var(--space-5); font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-accent); }
.hero-focus span[aria-hidden] { color: #8b9ba5; }
.hero-intro { margin-top: var(--space-4); font-size: var(--text-sm); }
.hero .actions { margin-top: var(--space-6); }
.hero-visual { position: relative; width: 112%; margin-left: -4%; user-select: none; pointer-events: none; }
.hero-visual img { width: 100%; opacity: 0.8; transition: transform 500ms ease; }
.hero-visual-label { display: flex; justify-content: space-between; padding-inline: var(--space-6); color: var(--color-muted); font-family: var(--font-mono); font-size: 0.625rem; letter-spacing: 0.08em; }
.hero-visual-label:last-child { margin-top: var(--space-4); }
.hero:hover .hero-visual img { transform: translateY(-4px); }
.hero-foot { display: flex; justify-content: space-between; align-items: center; gap: var(--space-5); padding-block: var(--space-5); border-top: 1px solid var(--color-line); }
.hero-foot p { font-family: var(--font-mono); font-size: 0.6875rem; letter-spacing: 0.06em; text-transform: uppercase; }
.hero-foot a { font-size: var(--text-xs); }

/* 6. Project cards -------------------------------------------------------- */
.project-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-6); }
.project-card { overflow: hidden; min-width: 0; border: 1px solid var(--color-line); border-radius: var(--radius-md); background: var(--color-surface); transition: transform var(--motion-fast) ease, border-color var(--motion-fast) ease, box-shadow var(--motion-fast) ease; }
.project-card:hover { transform: translateY(-4px); border-color: #aebfc8; box-shadow: 0 10px 28px #182d3b08; }
.project-image { position: relative; aspect-ratio: 18 / 11; overflow: hidden; background: var(--color-soft); border-bottom: 1px solid var(--color-line); }
.project-image img { width: 100%; height: 100%; object-fit: cover; transition: transform 300ms ease; }
.project-card:hover .project-image img { transform: scale(1.015); }
.project-body { padding: var(--space-6); }
.project-meta { display: flex; justify-content: space-between; align-items: center; gap: var(--space-3); margin-bottom: var(--space-4); }
.project-category { font-family: var(--font-mono); font-size: 0.6875rem; letter-spacing: 0.065em; color: var(--color-accent); text-transform: uppercase; }
.project-card h3 { font-size: clamp(1.5rem, 2.2vw, 1.8rem); }
.project-description { margin-top: var(--space-3); font-size: var(--text-sm); }
.technology-list { list-style: none; display: flex; flex-wrap: wrap; gap: var(--space-2); margin-top: var(--space-5); }
.technology-list li { padding: var(--space-1) var(--space-2); background: var(--color-soft); border-radius: var(--radius-sm); color: var(--color-muted); font-family: var(--font-mono); font-size: 0.6875rem; }
.project-footer { display: flex; justify-content: space-between; align-items: center; gap: var(--space-3); margin-top: var(--space-5); padding-top: var(--space-4); border-top: 1px solid var(--color-line); }
.project-footer > span { font-size: var(--text-xs); color: var(--color-muted); }
.project-footer .text-link { font-size: var(--text-xs); }
.project-card-text { grid-column: 1 / -1; }
.project-card-text .project-body { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-7); align-items: center; }
.project-card-text .project-meta { justify-content: start; }
.project-card-text .technology-list { margin-top: 0; }

/* 7. Background, education and contact ------------------------------------ */
.split-layout { display: grid; grid-template-columns: 0.75fr 1.25fr; gap: var(--space-9); }
.background-copy .lead { font-size: clamp(1.25rem, 2.2vw, 1.65rem); line-height: 1.55; color: var(--color-ink); letter-spacing: -0.015em; }
.background-copy > * + * { margin-top: var(--space-5); }
.focus-list { display: flex; flex-wrap: wrap; gap: var(--space-3) var(--space-5); list-style: none; padding-top: var(--space-5); border-top: 1px solid var(--color-line); color: var(--color-muted); font-family: var(--font-mono); font-size: var(--text-xs); }
.focus-list li::before { content: "+"; margin-right: var(--space-2); color: var(--color-accent); }
.timeline { list-style: none; }
.timeline li { display: grid; grid-template-columns: 6.5rem 1fr; gap: var(--space-5); padding-block: var(--space-6); border-top: 1px solid var(--color-line); }
.timeline li:first-child { padding-top: 0; border-top: 0; }
.timeline li:last-child { padding-bottom: 0; }
.timeline-label { padding-top: var(--space-1); font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-muted); }
.timeline h3 { font-size: 1.125rem; letter-spacing: -0.02em; }
.timeline p { margin-top: var(--space-2); font-size: var(--text-sm); }
.timeline .placeholder-badge { margin-top: var(--space-3); }
.contact-section { background: var(--color-dark); border-color: var(--color-dark); color: white; }
.contact-section .section-number, .contact-section p, .contact-section .unavailable { color: #bfcdd5; }
.contact-section .split-layout { align-items: center; }
.contact-section h2 { max-width: 25rem; }
.contact-section p:not(.section-number) { margin-top: var(--space-4); max-width: 26rem; }
.contact-email { display: inline-flex; gap: var(--space-5); align-items: baseline; font-size: clamp(1.5rem, 3.7vw, 2.65rem); letter-spacing: -0.045em; text-decoration-thickness: 1px; text-underline-offset: 0.25em; }
.contact-email:hover { color: #d5e6ef; }
.contact-social { list-style: none; display: flex; flex-wrap: wrap; gap: var(--space-6); margin-top: var(--space-6); }
.contact-social a { display: inline-block; padding-block: var(--space-2); font-size: var(--text-sm); }
.contact-section :focus-visible { outline-color: #d5e6ef; }
.site-footer { border-top: 1px solid var(--color-line); padding-block: var(--space-5); }
.footer-inner { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: var(--space-3); }
.site-footer p, .site-footer a { font-size: var(--text-xs); color: var(--color-muted); }
.footer-domain { font-family: var(--font-mono); letter-spacing: 0.02em; }

/* 8. About, project index and case studies -------------------------------- */
.page-hero { padding-block: var(--space-9) var(--space-8); }
.page-hero .eyebrow { margin-bottom: var(--space-6); }
.page-hero h1 { max-width: 56rem; font-size: clamp(2.75rem, 6vw, 4.75rem); }
.page-hero .lead { max-width: 40rem; margin-top: var(--space-5); }
.page-hero .placeholder-note { margin-top: var(--space-4); }
.page-hero .text-link { margin-bottom: var(--space-5); }
.page-hero .placeholder-badge { margin-top: var(--space-5); }
.interest-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-5); }
.interest-card { min-width: 0; }
.interest-image { position: relative; display: grid; place-content: center; aspect-ratio: 4 / 5; overflow: hidden; padding: var(--space-6); border: 1px solid var(--color-line); border-radius: var(--radius-md); background-color: #e8eeed; background-image: linear-gradient(#182d3b05 1px, transparent 1px), linear-gradient(90deg, #182d3b05 1px, transparent 1px); background-size: 32px 32px; text-align: center; }
.interest-image img { width: 100%; height: 100%; object-fit: cover; }
.interest-image:has(img) { display: block; padding: 0; background: var(--color-soft); }
.interest-image .meta-label { color: var(--color-muted); }
.interest-image .image-symbol { font-size: 2.5rem; line-height: 1; color: #718694; margin-bottom: var(--space-5); font-weight: 300; }
.interest-image small { display: block; margin-top: var(--space-2); font-size: var(--text-xs); color: var(--color-muted); }
.interest-card figcaption { margin-top: var(--space-5); font-size: var(--text-lg); font-weight: 550; }
.interest-card > p { margin-top: var(--space-2); font-size: var(--text-sm); }
.cv-panel { padding: var(--space-6); background: var(--color-soft); border: 1px solid var(--color-line); border-radius: var(--radius-md); }
.cv-panel h3 { font-size: 1.25rem; }
.cv-panel p { margin-top: var(--space-3); }
.project-note { margin-top: var(--space-6); font-size: var(--text-sm); max-width: 44rem; }
.case-figure { margin-top: var(--space-7); border: 1px solid var(--color-line); border-radius: var(--radius-md); overflow: hidden; background: var(--color-soft); }
.case-figure img { width: 100%; max-height: 480px; object-fit: contain; }
.case-figure figcaption { padding: var(--space-3) var(--space-5); border-top: 1px solid var(--color-line); font-size: var(--text-xs); color: var(--color-muted); }
.case-facts { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-5); margin: var(--space-7) 0 0; padding-top: var(--space-5); border-top: 1px solid var(--color-line); }
.case-facts dt { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-muted); }
.case-facts dd { margin: var(--space-2) 0 0; font-size: var(--text-sm); }
.case-section + .case-section { margin-top: var(--space-7); padding-top: var(--space-7); border-top: 1px solid var(--color-line); }
.case-section h2 { font-size: var(--text-xl); }
.case-section p { margin-top: var(--space-4); }
.error-page { min-height: 70vh; display: grid; align-content: center; }
.error-page h1 { margin-block: var(--space-5); }
.error-page .actions { margin-top: var(--space-6); }

/* 9. Progressive animation: content stays visible without JavaScript ------ */
[data-reveal] { transition: opacity var(--motion-enter) ease, translate var(--motion-enter) ease; }
.project-card[data-reveal] { transition: opacity var(--motion-enter) ease, translate var(--motion-enter) ease, transform var(--motion-fast) ease, border-color var(--motion-fast) ease, box-shadow var(--motion-fast) ease; }
.reveal-pending { opacity: 0; translate: 0 14px; }
[data-reveal]:focus-within { opacity: 1; translate: none; transition: none; }

/* 10. Responsive layout --------------------------------------------------- */
@media (min-width: 1600px) {
  :root { --page-width: 1280px; }
  .hero-inner { min-height: 710px; }
}

@media (max-width: 1000px) {
  .brand-name { max-width: 8rem; line-height: 1.35; }
  .site-nav, .nav-list { gap: var(--space-4); }
  .nav-social { padding-left: var(--space-4); }
  .split-layout { gap: var(--space-7); grid-template-columns: 0.8fr 1.2fr; }
  .hero-inner { min-height: 590px; }
}

@media (max-width: 760px) {
  :root { --space-9: 4rem; --space-10: 5rem; }
  .header-inner { min-height: 72px; flex-wrap: wrap; gap: 0; padding-block: var(--space-3); }
  .brand-name { max-width: none; }
  .nav-ready .nav-toggle { display: inline-flex; }
  .site-nav { width: 100%; flex-direction: column; align-items: stretch; gap: var(--space-2); padding-block: var(--space-4) var(--space-2); }
  .nav-ready .site-nav { display: none; }
  .nav-ready.is-open .site-nav { display: flex; max-height: calc(100dvh - 90px); overflow-y: auto; }
  .nav-list { flex-wrap: wrap; gap: var(--space-2) var(--space-5); }
  .nav-social { border-left: 0; padding-left: 0; }
  .nav-social .unavailable { min-height: 36px; }
  .hero-inner { grid-template-columns: 1fr; min-height: auto; padding-top: var(--space-7); padding-bottom: var(--space-6); gap: var(--space-6); }
  .hero h1 { font-size: clamp(3.2rem, 10vw, 4.8rem); }
  .hero-role { max-width: 29rem; }
  .hero-visual { width: min(100%, 420px); margin-inline: auto; }
  .hero-visual img { max-height: 280px; width: 100%; object-fit: contain; }
  .hero-visual-label { padding-inline: var(--space-3); }
  .hero-visual-label:last-child { margin-top: 0; }
  .hero-foot { padding-block: var(--space-4); }
  .hero-foot p { max-width: 14rem; font-size: 0.625rem; }
  .section-heading { align-items: start; }
  .section-heading > .text-link { flex-shrink: 0; margin-top: var(--space-7); }
  .project-grid { gap: var(--space-5); }
  .project-body { padding: var(--space-5); }
  .project-meta { flex-wrap: wrap; gap: var(--space-2); }
  .project-footer { flex-wrap: wrap; }
  .split-layout { grid-template-columns: 1fr; gap: var(--space-6); }
  .interest-grid { gap: var(--space-4); }
  .interest-image { padding: var(--space-3); }
  .interest-image .meta-label { font-size: 0.625rem; }
  .contact-section .split-layout { gap: var(--space-7); }
  .contact-email { font-size: clamp(1.65rem, 6vw, 2.7rem); }
  .page-hero { padding-top: var(--space-7); }
}

@media (max-width: 540px) {
  .brand-name { font-size: 0.8125rem; }
  .brand { gap: var(--space-2); }
  .brand-mark { width: 32px; height: 32px; }
  .nav-toggle { padding-inline: var(--space-2); }
  .section-heading { flex-direction: column; gap: var(--space-3); }
  .section-heading > .text-link { margin-top: 0; }
  .project-grid, .interest-grid, .case-facts { grid-template-columns: 1fr; }
  .project-card-text .project-body { grid-template-columns: 1fr; gap: var(--space-5); }
  .project-footer { flex-wrap: nowrap; }
  .timeline li { grid-template-columns: 4.5rem 1fr; gap: var(--space-4); }
  .interest-image { aspect-ratio: 4 / 3; }
  .interest-grid { gap: var(--space-7); }
  .case-facts { gap: var(--space-4); }
}

/* 11. Motion preferences and printing ------------------------------------ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .reveal-pending { opacity: 1; translate: none; }
  .hero:hover .hero-visual img, .project-card:hover, .project-card:hover .project-image img, .button:hover, .text-link:hover span[aria-hidden] { transform: none; }
}

@media print {
  :root { --color-bg: white; --color-ink: black; --color-muted: #333333; }
  .site-header, .skip-link, .hero-visual, .site-footer, .nav-toggle { display: none; }
  .container { width: 100%; }
  .section, .page-hero { padding-block: var(--space-6); }
  .hero-inner { display: block; min-height: auto; }
  .contact-section { background: white; color: black; }
  .contact-section p, .contact-section .section-number, .contact-section .unavailable { color: #333333; }
  .reveal-pending { opacity: 1; translate: none; }
  .project-card, .timeline li, .interest-card { break-inside: avoid; }
}