/* ============================================================
   MERT TURELI — PORTFOLIO
   Design system: "Drafting Paper" (warm editorial)
   Type: Fraunces (display) · Inter (body) · JetBrains Mono (labels)
   All color pairs verified WCAG AA (4.5:1+) against bg & surface.
   To re-skin (e.g. business variant): change the tokens below only.
   ============================================================ */

:root {
  /* palette — drafting paper */
  --bg:            #FAF7F0;
  --surface:       #F1ECE2;
  --text:          #221F1A;
  --text-2:        #57534E;
  --accent:        #9C4221;
  --accent-hover:  #7C2D12;
  --border:        #E3DCCB;
  --grid-line:     rgba(34, 31, 26, 0.055);

  /* type */
  --font-display: "Fraunces", Georgia, serif;
  --font-body:    "Inter", system-ui, -apple-system, sans-serif;
  --font-mono:    "JetBrains Mono", Consolas, monospace;

  --text-h1:    clamp(2.5rem, 1.2rem + 4.5vw, 4.25rem);
  --text-h2:    clamp(1.75rem, 1.3rem + 1.8vw, 2.5rem);
  --text-h3:    clamp(1.25rem, 1.1rem + 0.6vw, 1.5rem);
  --text-body:  1.125rem;
  --text-small: 0.875rem;
  --text-label: 0.8125rem;

  /* spacing (8px base) */
  --space-1: 0.25rem;  --space-2: 0.5rem;  --space-3: 0.75rem;
  --space-4: 1rem;     --space-6: 1.5rem;  --space-8: 2rem;
  --space-12: 3rem;    --space-16: 4rem;   --space-24: 6rem;

  --section-gap: clamp(4rem, 3rem + 6vw, 8rem);
  --container: 1120px;
  --radius: 8px;
}

/* ---------- base ---------- */

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

html { scroll-behavior: smooth; }

/* paper grain baked into the body background (opacity lives inside the SVG) —
   a separate fixed overlay layer stalls compositing/capture in some browsers */
body {
  margin: 0;
  background-color: var(--bg);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='240' height='240'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/%3E%3C/filter%3E%3Crect width='240' height='240' filter='url(%23n)' opacity='0.028'/%3E%3C/svg%3E");
  color: var(--text);
  font-family: var(--font-body);
  font-size: var(--text-body);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

::selection { background: var(--accent); color: var(--bg); }

h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -0.015em;
  margin: 0 0 var(--space-4);
}
h1 { font-size: var(--text-h1); line-height: 1.05; }
h2 { font-size: var(--text-h2); }
h3 { font-size: var(--text-h3); line-height: 1.3; }

p { margin: 0 0 var(--space-4); max-width: 68ch; }

img, svg.ph { max-width: 100%; height: auto; display: block; }

a {
  color: var(--accent);
  text-decoration: none;
  background-image: linear-gradient(currentColor, currentColor);
  background-repeat: no-repeat;
  background-size: 0% 1px;
  background-position: 0 100%;
  transition: background-size 200ms ease-out, color 150ms ease-out;
}
a:hover { color: var(--accent-hover); background-size: 100% 1px; }

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

.container {
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: clamp(1.25rem, 4vw, 3rem);
}

section { padding-block: calc(var(--section-gap) / 2); }

/* mono section labels — drawing sheet numbers */
.label {
  font-family: var(--font-mono);
  font-size: var(--text-label);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  display: block;
  margin-bottom: var(--space-4);
}

.meta-row {
  font-family: var(--font-mono);
  font-size: var(--text-label);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-2);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
}

/* arrow nudge */
.arrow { display: inline-block; transition: transform 150ms ease-out; }
a:hover .arrow { transform: translateX(4px); }

/* fill-in placeholder — replace via PROJECT_INTAKE.md */
.fill {
  background: rgba(156, 66, 33, 0.08);
  border-bottom: 1px dashed var(--accent);
  padding: 0 0.2em;
  border-radius: 2px;
  font-style: italic;
  cursor: help;
}

/* ---------- header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}
.wordmark {
  font-family: var(--font-mono);
  font-size: var(--text-label);
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text);
}
.site-nav { display: flex; gap: var(--space-6); }
.site-nav a {
  color: var(--text-2);
  font-size: var(--text-small);
  font-weight: 500;
}
.site-nav a:hover { color: var(--accent-hover); }

/* ---------- hero ---------- */

.hero {
  position: relative;
  padding-block: clamp(5rem, 12vh, 9rem) clamp(4rem, 10vh, 7rem);
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 32px 32px;
  -webkit-mask-image: radial-gradient(ellipse 90% 80% at 30% 20%, black 30%, transparent 75%);
  mask-image: radial-gradient(ellipse 90% 80% at 30% 20%, black 30%, transparent 75%);
  pointer-events: none;
}
.hero .container { position: relative; }
.hero h1 { max-width: 18ch; }
.hero .intro { max-width: 52ch; color: var(--text-2); margin-top: var(--space-6); }
.hero .hero-sub {
  font-family: var(--font-mono);
  font-size: var(--text-label);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin: var(--space-3) 0 0;
}
.hero .bio { font-size: 1rem; max-width: 58ch; margin-top: var(--space-4); }
.hero .meta-row { margin-top: var(--space-8); }
.hero-actions { display: flex; flex-wrap: wrap; gap: var(--space-4); margin-top: var(--space-8); }

/* hand-drawn underline — use exactly once */
.scribbled { position: relative; white-space: nowrap; }
.scribbled svg {
  position: absolute;
  left: -2%;
  bottom: -0.18em;
  width: 104%;
  height: 0.28em;
  color: var(--accent);
  overflow: visible;
}
.scribbled svg path {
  stroke-dasharray: 220;
  stroke-dashoffset: 220;
  animation: draw-in 700ms ease-out 400ms forwards;
}
@keyframes draw-in { to { stroke-dashoffset: 0; } }

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-body);
  font-size: var(--text-small);
  font-weight: 600;
  padding: 0.75rem 1.375rem;
  border-radius: var(--radius);
  border: 1px solid var(--accent);
  background: var(--accent);
  color: var(--bg);
  background-image: none;
  transition: background-color 150ms ease-out, border-color 150ms ease-out,
              color 150ms ease-out, transform 150ms ease-out;
}
.btn:hover { background: var(--accent-hover); border-color: var(--accent-hover); color: var(--bg); transform: translateY(-1px); }
.btn.ghost { background: transparent; color: var(--accent); }
.btn.ghost:hover { background: var(--accent); color: var(--bg); }

/* ---------- featured projects — editorial rows ---------- */

.project-rows { display: flex; flex-direction: column; gap: var(--space-16); }

.project-row {
  display: grid;
  grid-template-columns: 7fr 5fr;
  gap: var(--space-8);
  align-items: center;
}
.project-row:nth-child(even) .project-media { order: 2; }

.project-media {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--surface);
  transition: border-color 200ms ease-out, transform 200ms ease-out, box-shadow 200ms ease-out;
}
.project-row:hover .project-media {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 12px 32px -16px rgba(34, 31, 26, 0.25);
}

.project-body .label { margin-bottom: var(--space-2); }
.project-body h3 { margin-bottom: var(--space-3); }
.project-body p { color: var(--text-2); font-size: 1rem; }

.tags { display: flex; flex-wrap: wrap; gap: var(--space-2); margin: var(--space-4) 0; padding: 0; list-style: none; }
.tags li {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--text-2);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0.2rem 0.55rem;
}

.metric {
  font-family: var(--font-mono);
  font-size: var(--text-small);
  color: var(--text);
  font-variant-numeric: tabular-nums;
  display: block;
  margin-bottom: var(--space-3);
}
.metric strong { color: var(--accent); font-weight: 600; }

/* ---------- spec cards — image-free project media ---------- */

.spec-card {
  aspect-ratio: 3 / 2;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: var(--space-6);
  background-color: var(--surface);
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 24px 24px;
  color: var(--text);
}
.spec-card .sc-label {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  display: flex;
  justify-content: space-between;
  gap: var(--space-2);
}
.spec-card .sc-label span:last-child { color: var(--text-2); }
.spec-card .sc-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-4) var(--space-6);
}
.spec-card .sc-stat strong {
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 1rem + 1.4vw, 2rem);
  font-weight: 600;
  line-height: 1.1;
  display: block;
  letter-spacing: -0.01em;
}
.spec-card .sc-stat small {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text-2);
  display: block;
  margin-top: 0.2rem;
}
.spec-card .sc-foot {
  border-top: 1px solid var(--border);
  padding-top: var(--space-3);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-2);
}

/* ---------- more projects — table-like list ---------- */

.more-list { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--border); }
.more-list li { border-bottom: 1px solid var(--border); }
.more-list a, .more-list .row {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 5fr) 2fr;
  gap: var(--space-4);
  align-items: baseline;
  padding: var(--space-4) var(--space-2);
  color: var(--text);
  background-image: none;
  transition: background-color 150ms ease-out;
}
.more-list a:hover { background-color: var(--surface); color: var(--text); }
.more-list .title { font-weight: 600; font-size: 1rem; }
.more-list .desc { color: var(--text-2); font-size: var(--text-small); }
.more-list .year {
  font-family: var(--font-mono);
  font-size: var(--text-label);
  color: var(--text-2);
  text-align: right;
  font-variant-numeric: tabular-nums;
}

/* ---------- experience ---------- */

.xp-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; }
.xp {
  display: grid;
  grid-template-columns: 3rem minmax(0, 4fr) minmax(0, 7fr);
  gap: var(--space-4);
  padding: var(--space-6) 0;
  border-top: 1px solid var(--border);
}
.xp-num {
  font-family: var(--font-mono);
  font-size: var(--text-label);
  color: var(--accent);
  padding-top: 0.3rem;
}
.xp h3 { font-family: var(--font-body); font-size: 1.0625rem; font-weight: 600; margin-bottom: var(--space-1); }
.xp .org { color: var(--text-2); font-size: var(--text-small); }
.xp .dates {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--text-2);
  display: block;
  margin-top: var(--space-2);
}
.xp ul { margin: 0; padding-left: 1.1rem; color: var(--text-2); font-size: 1rem; }
.xp ul li { margin-bottom: var(--space-2); }

/* ---------- skills ---------- */

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-8);
}
.skills-grid h3 {
  font-family: var(--font-mono);
  font-size: var(--text-label);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-2);
  margin-bottom: var(--space-3);
}

/* ---------- about ---------- */

.about-grid {
  display: grid;
  grid-template-columns: 7fr 4fr;
  gap: var(--space-12);
  align-items: start;
}
.about-grid .project-media { max-width: 380px; }

/* ---------- contact ---------- */

.contact { text-align: left; }
.contact .big-link {
  font-family: var(--font-display);
  font-size: var(--text-h2);
  font-weight: 600;
  letter-spacing: -0.01em;
}

/* ---------- footer ---------- */

.site-footer {
  border-top: 1px solid var(--border);
  margin-top: var(--section-gap);
  padding: var(--space-12) 0 var(--space-8);
  color: var(--text-2);
  font-size: var(--text-small);
}
.site-footer .container { display: flex; flex-wrap: wrap; justify-content: space-between; gap: var(--space-4); }
.colophon { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.03em; }

/* ---------- case study pages ---------- */

.case-hero { padding-top: var(--space-16); }
.case-hero h1 { max-width: 22ch; font-size: clamp(2rem, 1.2rem + 3vw, 3.25rem); }
.case-hero .intro { color: var(--text-2); max-width: 60ch; }

/* engineering drawing title block */
.title-block {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-8) 0;
  font-size: var(--text-small);
}
.title-block th, .title-block td {
  border: 1px solid var(--border);
  padding: var(--space-3) var(--space-4);
  text-align: left;
  vertical-align: top;
}
.title-block th {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-2);
  background: var(--surface);
  width: 12%;
  white-space: nowrap;
}
.title-block td { font-variant-numeric: tabular-nums; }

.case-body { max-width: 760px; }
.case-body h2 { margin-top: var(--space-16); }
.case-body figure { margin: var(--space-8) 0; }
.case-body figcaption {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.03em;
  color: var(--text-2);
  margin-top: var(--space-2);
}
.case-body .project-media:hover { transform: none; border-color: var(--border); box-shadow: none; }

.constraints { list-style: none; padding: 0; }
.constraints li {
  padding: var(--space-3) 0 var(--space-3) var(--space-6);
  border-bottom: 1px solid var(--border);
  color: var(--text-2);
  font-size: 1rem;
  position: relative;
}
.constraints li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-family: var(--font-mono);
}

.results-list { list-style: none; padding: 0; }
.results-list li {
  font-family: var(--font-mono);
  font-size: var(--text-small);
  font-variant-numeric: tabular-nums;
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--border);
}
.results-list strong { color: var(--accent); font-weight: 600; }

.case-nav {
  margin-top: var(--space-24);
  padding-top: var(--space-8);
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  gap: var(--space-4);
}

/* ---------- reveal on scroll ---------- */

.reveal { opacity: 0; transform: translateY(8px); transition: opacity 350ms ease-out, transform 350ms ease-out; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- responsive ---------- */

@media (max-width: 900px) {
  .project-row, .about-grid { grid-template-columns: 1fr; }
  .project-row:nth-child(even) .project-media { order: 0; }
  .xp { grid-template-columns: 2.5rem 1fr; }
  .xp .xp-role { grid-column: 2; }
  .xp ul { grid-column: 2; }
}

@media (max-width: 640px) {
  .site-nav { gap: var(--space-4); }
  .site-nav a.hide-mobile { display: none; }
  .more-list a, .more-list .row { grid-template-columns: 1fr auto; }
  .more-list .desc { display: none; }
  .case-nav { flex-direction: column; }
}

/* ---------- reduced motion ---------- */

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition-duration: 0.01ms !important; }
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; }
  .scribbled svg path { stroke-dashoffset: 0; }
}

/* Recommendation quote (About section) */
.rec-quote {
  border-left: 2px solid var(--accent);
  padding-left: var(--space-6);
  margin: var(--space-6) 0;
}
.rec-quote p { font-style: italic; }
.rec-quote cite {
  display: block;
  margin-top: var(--space-4);
  font-style: normal;
  font-size: 0.9rem;
  color: var(--accent);
}