/* ==========================================================================
   Michał Leszczyński — Personal Site
   Design system: Palette 02 "Slate Modernist"
   Fonts: DM Serif Display · Sora · DM Mono
   ========================================================================== */

/* ── Design tokens ─────────────────────────────────────────────────────── */
:root {
  --ground:     #f1f2f4;
  --ground-alt: #e7e9ec;
  --ink:        #0d1622;
  --ink-soft:   #5d646e;
  --blue:       #2b4b6f;
  --rule:       #c8cdd3;
  --rule-lite:  #dbdee2;
  --accent:     #3d6db0;

  --font-serif: "DM Serif Display", Georgia, "Times New Roman", serif;
  --font-sans:  "Sora", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-mono:  "DM Mono", "SF Mono", Menlo, monospace;

  --max-w: 1200px;
  --pad-x: 56px;
  --ease:  cubic-bezier(0.2, 0.65, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
}

html, body {
  margin: 0;
  padding: 0;
}

body {
  background: var(--ground);
  color: var(--ink);
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 { margin: 0; }
p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul { margin: 0; padding: 0; list-style: none; }

::selection { background: var(--ink); color: var(--ground); }

/* ── Page transition (fires on every load) ──────────────────────────────── */
main {
  animation: pageIn 0.32s var(--ease) both;
}

@keyframes pageIn {
  from { opacity: 0; transform: translateY(6px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── Layout helpers ─────────────────────────────────────────────────────── */
.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--pad-x);
}

.section {
  padding: 96px 0;
}

.rule {
  height: 1px;
  background: var(--rule);
  width: 100%;
}

.rule--ink {
  background: var(--ink);
}

/* ── Typography primitives ──────────────────────────────────────────────── */
.eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.mark {
  color: var(--accent);
}

/* ── Buttons ────────────────────────────────────────────────────────────── */
.btn {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.10em;
  text-transform: uppercase;
  padding: 14px 24px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: transform 0.15s var(--ease);
  border: none;
  white-space: nowrap;
}

.btn:hover { transform: translateY(-1px); }

.btn-primary {
  background: var(--ink);
  color: var(--ground);
}

.btn-outline {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--ink);
}

/* ── Navigation ─────────────────────────────────────────────────────────── */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--ground) 92%, transparent);
  backdrop-filter: saturate(140%) blur(8px);
  -webkit-backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--rule);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding-top: 20px;
  padding-bottom: 20px;
}

.wordmark {
  font-family: var(--font-serif);
  font-size: 22px;
  letter-spacing: -0.015em;
  color: var(--ink);
  line-height: 1;
  white-space: nowrap;
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-links a {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
  border-bottom: 1px solid transparent;
  padding-bottom: 3px;
  transition: color 0.15s, border-color 0.15s;
  white-space: nowrap;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--ink);
  border-bottom-color: var(--ink);
}

.nav-links a.nav-cta {
  font-weight: 500;
}

/* Hamburger (mobile) */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  color: var(--ink);
  flex-direction: column;
  gap: 5px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--ink);
  transition: transform 0.2s, opacity 0.2s;
}

.nav-toggle.open span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

/* ── Hero ───────────────────────────────────────────────────────────────── */
.hero {
  padding-top: 88px;
  padding-bottom: 56px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.4fr 0.9fr;
  gap: 72px;
  align-items: center;
}

.hero-eyebrow {
  margin-bottom: 24px;
}

.hero-heading {
  font-family: var(--font-serif);
  font-size: clamp(52px, 7.5vw, 108px);
  line-height: 0.94;
  letter-spacing: -0.03em;
  font-weight: 400;
}

.hero-heading em { font-style: italic; }

.hero-intro {
  font-family: var(--font-sans);
  font-size: 19px;
  line-height: 1.6;
  color: var(--ink-soft);
  margin-top: 32px;
  max-width: 500px;
}

.hero-cta {
  display: flex;
  gap: 12px;
  margin-top: 36px;
  flex-wrap: wrap;
}

/* Portrait */
.portrait-wrap {
  position: relative;
}

.portrait-img {
  width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  object-position: center 15%;
  display: block;
  border: 1px solid var(--rule);
}

.portrait-placeholder {
  width: 100%;
  aspect-ratio: 4 / 5;
  background: var(--ground-alt);
  border: 1px solid var(--rule);
  display: flex;
  align-items: center;
  justify-content: center;
}

.portrait-placeholder span {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.portrait-meta {
  margin-top: 14px;
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.portrait-meta .available { color: var(--accent); }

.hero-rule {
  margin-top: 80px;
}

/* ── Experience section ─────────────────────────────────────────────────── */
.experience {
  padding-top: 80px;
  padding-bottom: 96px;
}

.section-label {
  margin-bottom: 48px;
}

.section-label .eyebrow {
  margin-bottom: 16px;
}

.section-label h2 {
  font-family: var(--font-serif);
  font-size: clamp(34px, 4vw, 52px);
  line-height: 1.05;
  letter-spacing: -0.025em;
  font-weight: 400;
  max-width: 680px;
}

.section-label h2 em { font-style: italic; }

.section-label .intro {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.65;
  color: var(--ink-soft);
  margin-top: 20px;
  max-width: 620px;
}

.exp-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border-top: 1px solid var(--ink);
}

.exp-card {
  padding: 32px 32px 32px 0;
  border-right: 1px solid var(--rule);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.exp-card:last-child {
  border-right: none;
  padding-right: 0;
  padding-left: 32px;
}

.exp-card:nth-child(2) {
  padding-left: 32px;
}

.exp-period {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 6px;
}

.exp-org {
  font-family: var(--font-sans);
  font-size: 13px;
  color: var(--ink-soft);
  letter-spacing: 0.03em;
}

.exp-role {
  font-family: var(--font-serif);
  font-size: 26px;
  line-height: 1.1;
  letter-spacing: -0.015em;
  color: var(--ink);
}

.exp-desc {
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
  margin: 0;
  flex: 1;
}

.exp-list {
  list-style: none;
  padding: 0;
  margin: 0;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.exp-list li {
  font-family: var(--font-sans);
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-soft);
  padding-left: 14px;
  position: relative;
}

.exp-list li::before {
  content: "▪";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 10px;
  top: 3px;
}

.exp-metric {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding-top: 20px;
  border-top: 1px solid var(--rule);
  margin-top: auto;
}

.metric-val {
  font-family: var(--font-serif);
  font-size: 36px;
  line-height: 1;
  letter-spacing: -0.025em;
  color: var(--blue);
}

.metric-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

/* ── Footer ─────────────────────────────────────────────────────────────── */
.site-footer {
  background: var(--ground-alt);
  border-top: 1px solid var(--rule);
}

.footer-main {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 48px;
  padding-top: 56px;
  padding-bottom: 56px;
}

.footer-wordmark {
  font-family: var(--font-serif);
  font-size: 28px;
  line-height: 1.0;
  letter-spacing: -0.015em;
  display: block;
  margin-bottom: 14px;
}

.footer-tagline {
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink-soft);
  max-width: 260px;
}

.footer-col {
  display: flex;
  flex-direction: column;
}

.footer-col .eyebrow {
  margin-bottom: 16px;
}

.footer-col a,
.footer-col span {
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink);
  transition: color 0.15s;
}

.footer-col span { color: var(--ink-soft); }

.footer-col a:hover { color: var(--blue); }

.footer-bottom {
  border-top: 1px solid var(--rule);
}

.footer-bottom-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 20px;
  padding-bottom: 20px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

/* ── Page header (interior pages) ───────────────────────────────────────── */
.page-header {
  padding-top: 80px;
  padding-bottom: 56px;
}

.page-header .eyebrow {
  margin-bottom: 20px;
}

.page-header h1 {
  font-family: var(--font-serif);
  font-size: clamp(48px, 7vw, 88px);
  line-height: 0.98;
  letter-spacing: -0.025em;
  font-weight: 400;
  max-width: 900px;
}

.page-header h1 em { font-style: italic; }

.page-header .intro {
  font-family: var(--font-sans);
  font-size: 20px;
  line-height: 1.55;
  color: var(--ink-soft);
  margin-top: 28px;
  max-width: 700px;
}

.page-header .rule {
  margin-top: 56px;
}

/* ── Responsive ─────────────────────────────────────────────────────────── */
@media (max-width: 960px) {
  :root { --pad-x: 36px; }

  .hero-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .hero-portrait {
    order: -1;
    max-width: 300px;
  }

  .exp-grid {
    grid-template-columns: 1fr;
    border-top: none;
  }

  .exp-card {
    padding: 28px 0;
    border-right: none;
    border-top: 1px solid var(--rule);
  }

  .exp-card:first-child { border-top: 1px solid var(--ink); }
  .exp-card:nth-child(2) { padding-left: 0; }
  .exp-card:last-child   { padding-left: 0; }

  .footer-main {
    grid-template-columns: 1fr 1fr;
    gap: 36px;
  }

  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  :root { --pad-x: 20px; }

  .nav-links  { display: none; }
  .nav-toggle { display: flex; }

  /* Mobile menu — shown when JS adds .nav-open to <header> */
  .site-nav.nav-open .nav-links {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 12px 0 20px;
    border-top: 1px solid var(--rule);
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--ground);
    padding: 16px var(--pad-x) 24px;
    box-shadow: 0 8px 24px rgba(13,22,34,0.08);
  }

  .site-nav.nav-open .nav-links a {
    padding: 10px 0;
    font-size: 13px;
    border-bottom: 1px solid var(--rule-lite);
    width: 100%;
  }

  .site-nav.nav-open .nav-links a:last-child {
    border-bottom: none;
  }

  .hero { padding-top: 48px; }
  .section { padding: 64px 0; }
  .hero-rule { margin-top: 56px; }

  .footer-main {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .footer-bottom-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
}