/* ============================================
   TIANA — PM PORTFOLIO
   Design system: ink/paper/emerald/amber
   Display: Space Grotesk · Body: Inter · Utility: IBM Plex Mono
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;500;600;700&family=Inter:wght@400;500;600;700&family=IBM+Plex+Mono:wght@400;500&display=swap');

:root {
  --ink: #14171C;
  --ink-soft: #4A4F58;
  --paper: #FAFAF8;
  --card: #F0EFEA;
  --hairline: #DAD7CF;
  --emerald: #0F6E5C;
  --emerald-deep: #0A4E41;
  --amber: #E8A33D;
  --coral: #E1553C;
  --white: #FFFFFF;

  --font-display: 'Space Grotesk', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-mono: 'IBM Plex Mono', monospace;

  --max-w: 1120px;
  --pad: clamp(1.25rem, 4vw, 3rem);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }

a {
  color: inherit;
  text-decoration: none;
}

.wrap {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--pad);
}

/* ---------- Typography ---------- */

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.1;
  margin: 0;
  letter-spacing: -0.01em;
}

h1 { font-size: clamp(2.4rem, 6vw, 4.6rem); font-weight: 700; }
h2 { font-size: clamp(1.7rem, 3.6vw, 2.6rem); }
h3 { font-size: clamp(1.2rem, 2.2vw, 1.5rem); }

p { margin: 0 0 1rem; color: var(--ink-soft); }
p:last-child { margin-bottom: 0; }

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--emerald);
  display: inline-flex;
  align-items: center;
  gap: 0.5em;
}

.eyebrow::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--amber);
  border-radius: 1px;
}

/* ---------- Nav ---------- */

header.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(250, 250, 248, 0.9);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--hairline);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.1rem var(--pad);
  max-width: var(--max-w);
  margin: 0 auto;
}

.nav-logo {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 0.95rem;
  letter-spacing: -0.02em;
}

.nav-logo span { color: var(--emerald); }

.nav-links {
  display: flex;
  gap: clamp(1rem, 2.5vw, 2.2rem);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.nav-links a {
  position: relative;
  padding: 0.2rem 0;
  color: var(--ink-soft);
  transition: color 0.15s ease;
}

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

.nav-links a.active::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -4px;
  height: 2px;
  background: var(--amber);
}

.nav-toggle { display: none; }

@media (max-width: 720px) {
  .nav-links { position: fixed; top: 60px; left: 0; right: 0; background: var(--paper); flex-direction: column; padding: 1.5rem var(--pad); border-bottom: 1px solid var(--hairline); display: none; gap: 1.2rem; }
  .nav-links.open { display: flex; }
  .nav-toggle { display: block; font-family: var(--font-mono); font-size: 0.85rem; background: none; border: 1px solid var(--hairline); border-radius: 6px; padding: 0.4rem 0.7rem; cursor: pointer; }
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  padding: 0.75rem 1.3rem;
  border-radius: 6px;
  border: 1px solid var(--ink);
  transition: transform 0.15s ease, background 0.15s ease, color 0.15s ease;
}

.btn-primary { background: var(--ink); color: var(--paper); }
.btn-primary:hover { background: var(--emerald); border-color: var(--emerald); transform: translateY(-1px); }

.btn-ghost { background: transparent; color: var(--ink); }
.btn-ghost:hover { background: var(--ink); color: var(--paper); transform: translateY(-1px); }

/* ---------- Decision log (signature element) ---------- */

.decision-log {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  border: 1px solid var(--hairline);
  border-radius: 10px;
  background: var(--white);
  overflow: hidden;
}

.decision-log .log-head {
  padding: 0.7rem 1.1rem;
  border-bottom: 1px solid var(--hairline);
  color: var(--ink-soft);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  display: flex;
  justify-content: space-between;
}

.log-line {
  display: flex;
  gap: 0.8rem;
  padding: 0.85rem 1.1rem;
  border-bottom: 1px solid var(--hairline);
  align-items: baseline;
}

.log-line:last-child { border-bottom: none; }

.log-line .tag { color: var(--emerald); flex-shrink: 0; }
.log-line .tag.decided { color: var(--emerald); }
.log-line .tag.shipped { color: var(--coral); }
.log-line .tag.learned { color: var(--amber); }
.log-line .msg { color: var(--ink); }

/* ---------- Sections ---------- */

section { padding: clamp(3rem, 8vw, 6rem) 0; }
.border-top { border-top: 1px solid var(--hairline); }

/* ---------- Hero ---------- */

.hero {
  padding-top: clamp(3rem, 9vw, 7rem);
  padding-bottom: clamp(2.5rem, 6vw, 4rem);
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: clamp(2rem, 5vw, 4rem);
  align-items: end;
}

@media (max-width: 860px) {
  .hero { grid-template-columns: 1fr; }
}

.hero h1 { margin-bottom: 1.3rem; }
.hero .lede { font-size: 1.15rem; max-width: 46ch; }
.hero-actions { display: flex; gap: 0.9rem; margin-top: 2rem; flex-wrap: wrap; }

/* ---------- Project grid ---------- */

.project-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

@media (max-width: 720px) { .project-grid { grid-template-columns: 1fr; } }

.project-card {
  border: 1px solid var(--hairline);
  border-radius: 12px;
  background: var(--white);
  padding: 1.8rem;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
  transition: border-color 0.15s ease, transform 0.15s ease;
}

.project-card:hover { border-color: var(--emerald); transform: translateY(-2px); }

.project-card .num {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--ink-soft);
}

.project-card h3 { font-size: 1.35rem; }

.tag-row { display: flex; gap: 0.5rem; flex-wrap: wrap; margin-top: 0.3rem; }

.tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  background: var(--card);
  color: var(--ink-soft);
}

.card-link {
  margin-top: auto;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--emerald);
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.project-card:hover .card-link { text-decoration: underline; }

/* ---------- Case study layout ---------- */

.cs-hero {
  padding-top: clamp(2.5rem, 6vw, 4rem);
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--hairline);
}

.cs-hero .eyebrow { margin-bottom: 1rem; }
.cs-hero .lede { font-size: 1.1rem; max-width: 58ch; margin-top: 1rem; }

.cs-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  margin-top: 2rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
}

.cs-meta .meta-item { display: flex; flex-direction: column; gap: 0.3rem; }
.cs-meta .meta-item .k { color: var(--ink-soft); text-transform: uppercase; letter-spacing: 0.06em; font-size: 0.7rem; }
.cs-meta .meta-item .v { color: var(--ink); }

.cs-section { padding: clamp(2.2rem, 5vw, 3.5rem) 0; border-bottom: 1px solid var(--hairline); }
.cs-section:last-of-type { border-bottom: none; }

.cs-section .eyebrow { margin-bottom: 1rem; }
.cs-section h2 { margin-bottom: 1.2rem; }

.cs-grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 2.5rem; }
@media (max-width: 780px) { .cs-grid-2 { grid-template-columns: 1fr; } }

.callout {
  background: var(--card);
  border-left: 3px solid var(--amber);
  border-radius: 4px;
  padding: 1.2rem 1.4rem;
  font-family: var(--font-body);
  font-size: 0.98rem;
}

.callout p { color: var(--ink); }

.screenshot-frame {
  border: 1px solid var(--hairline);
  border-radius: 10px;
  background: var(--white);
  padding: 0.8rem;
}

.screenshot-frame .placeholder {
  aspect-ratio: 16/9;
  background: repeating-linear-gradient(135deg, var(--card), var(--card) 10px, var(--white) 10px, var(--white) 20px);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--ink-soft);
  text-align: center;
  padding: 1rem;
}

ul.plain { padding-left: 1.1rem; margin: 0; color: var(--ink-soft); }
ul.plain li { margin-bottom: 0.5rem; }
ul.plain li::marker { color: var(--emerald); }

.cs-nav-footer {
  display: flex;
  justify-content: space-between;
  padding: 2.5rem var(--pad);
  max-width: var(--max-w);
  margin: 0 auto;
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

/* ---------- Footer ---------- */

footer.site-footer {
  border-top: 1px solid var(--hairline);
  padding: 2.5rem 0 3rem;
  margin-top: 2rem;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--ink-soft);
}

.footer-links { display: flex; gap: 1.5rem; }

/* ---------- Focus states ---------- */

a:focus-visible, button:focus-visible {
  outline: 2px solid var(--emerald);
  outline-offset: 3px;
  border-radius: 3px;
}