/* ─── Design tokens ──────────────────────────────────────────── */
:root {
  --rust:   #C4622D;
  --brown:  #6B4C3B;
  --tan:    #D4B896;
  --sand:   #F2EAD3;
  --sage:   #7A9E7E;
  --dark:   #1F1410;
  --text:   #2C1E17;
  --white:  #FFFFFF;
  --radius: 8px;
  --shadow: 0 2px 10px rgba(0,0,0,0.12);
  --font:   'Segoe UI', system-ui, -apple-system, sans-serif;
}

/* ─── Reset ──────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--sand);
  color: var(--text);
  line-height: 1.6;
}
img { max-width: 100%; display: block; }
a { color: var(--rust); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ─── Navigation ─────────────────────────────────────────────── */
.site-header {
  background: var(--dark);
  position: sticky;
  top: 0;
  z-index: 100;
}
.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 62px;
}
.nav-logo {
  font-size: 1.15rem;
  font-weight: 900;
  color: var(--white);
  letter-spacing: -0.3px;
  text-transform: uppercase;
  line-height: 1;
}
.nav-logo span { color: var(--rust); }
.nav-logo:hover { text-decoration: none; }

.nav-links {
  display: none;
  list-style: none;
  gap: 2rem;
  align-items: center;
}
.nav-links a {
  color: var(--tan);
  font-weight: 600;
  font-size: 0.9rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  transition: color 0.15s;
}
.nav-links a:hover,
.nav-links a.active { color: var(--rust); text-decoration: none; }

/* Hamburger button */
.hamburger {
  background: none;
  border: none;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 6px 4px;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--white);
  border-radius: 2px;
  transition: transform 0.22s, opacity 0.22s;
}
.hamburger[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.hamburger[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Mobile menu */
.nav-menu {
  display: none;
  background: var(--dark);
  border-top: 1px solid rgba(255,255,255,0.06);
  padding: 0.5rem 1.25rem 1rem;
}
.nav-menu.open { display: block; }
.nav-menu ul { list-style: none; }
.nav-menu a {
  display: block;
  padding: 0.75rem 0;
  color: var(--tan);
  font-weight: 600;
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  border-bottom: 1px solid rgba(255,255,255,0.06);
  transition: color 0.15s;
}
.nav-menu a:hover,
.nav-menu a.active { color: var(--rust); text-decoration: none; }

@media (min-width: 768px) {
  .hamburger    { display: none; }
  .nav-links    { display: flex; }
  .nav-menu     { display: none !important; }
}

/* ─── Hero ───────────────────────────────────────────────────── */
.hero {
  background: var(--dark);
  color: var(--white);
  padding: 5rem 1.25rem 4.5rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 80% 60% at 50% 100%, rgba(196,98,45,0.18) 0%, transparent 70%);
  pointer-events: none;
}
.hero h1 {
  font-size: clamp(2.5rem, 8vw, 4.2rem);
  font-weight: 900;
  line-height: 1.08;
  margin-bottom: 1rem;
  letter-spacing: -1.5px;
  position: relative;
}
.hero h1 em { color: var(--rust); font-style: normal; }
.hero p {
  max-width: 540px;
  margin: 0 auto 2.25rem;
  color: var(--tan);
  font-size: 1.1rem;
  line-height: 1.65;
  position: relative;
}
.hero-actions { display: flex; gap: 0.75rem; justify-content: center; flex-wrap: wrap; position: relative; }

/* ─── Buttons ────────────────────────────────────────────────── */
.btn {
  display: inline-block;
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: 0.95rem;
  cursor: pointer;
  border: 2px solid transparent;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
  text-decoration: none !important;
  white-space: nowrap;
}
.btn-primary  { background: var(--rust);        color: var(--white); border-color: var(--rust); }
.btn-primary:hover  { background: #aa5225; border-color: #aa5225; }
.btn-secondary { background: transparent; color: var(--tan); border-color: rgba(212,184,150,0.5); }
.btn-secondary:hover { background: rgba(212,184,150,0.12); border-color: var(--tan); }
.btn-outline { background: transparent; color: var(--rust); border-color: var(--rust); }
.btn-outline:hover { background: var(--rust); color: var(--white); }
.btn-sm { padding: 0.5rem 1.1rem; font-size: 0.875rem; }

/* ─── Section layout ─────────────────────────────────────────── */
.section {
  max-width: 1100px;
  margin: 0 auto;
  padding: 3.5rem 1.25rem;
}
.section-title {
  font-size: 1.5rem;
  font-weight: 900;
  color: var(--brown);
  margin-bottom: 0.4rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.section-subtitle {
  color: var(--brown);
  margin-bottom: 2rem;
  font-size: 0.95rem;
  opacity: 0.75;
}

/* ─── Card grid ──────────────────────────────────────────────── */
.card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}
@media (min-width: 560px)  { .card-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 900px)  { .card-grid.cols-3 { grid-template-columns: repeat(3, 1fr); } }
@media (min-width: 1000px) { .card-grid.cols-4 { grid-template-columns: repeat(4, 1fr); } }

/* Base card */
.card {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: box-shadow 0.2s, transform 0.2s;
}
.card:hover { box-shadow: 0 6px 20px rgba(0,0,0,0.16); transform: translateY(-2px); }

.card-image {
  width: 100%;
  aspect-ratio: 16/9;
  background: linear-gradient(135deg, var(--brown) 0%, var(--rust) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  color: rgba(255,255,255,0.25);
  overflow: hidden;
}
.card-image img { width: 100%; height: 100%; object-fit: cover; }

.card-body {
  padding: 1.25rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}
.card-tag {
  display: inline-block;
  background: var(--sage);
  color: var(--white);
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  padding: 0.2rem 0.55rem;
  border-radius: 4px;
  margin-bottom: 0.6rem;
}
.card-tag.tag-race  { background: var(--rust); }
.card-tag.tag-gear  { background: var(--brown); }
.card-tag.tag-skill { background: var(--sage); }

.card-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 0.4rem;
  line-height: 1.3;
}
.card-text {
  color: var(--text);
  font-size: 0.875rem;
  flex: 1;
  margin-bottom: 1rem;
  opacity: 0.8;
  line-height: 1.55;
}
.card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--brown);
  margin-top: auto;
}
.card-date { opacity: 0.7; }

/* Feature card (homepage) — larger */
.card-feature .card-image { aspect-ratio: 3/2; font-size: 5rem; }
.card-feature .card-title { font-size: 1.3rem; }
.card-feature .card-text  { font-size: 0.95rem; }

/* ─── Gear / product card ────────────────────────────────────── */
.product-card .card-image {
  aspect-ratio: 4/3;
  background: linear-gradient(135deg, #2a1e17 0%, #5a3c2a 100%);
}
.product-price {
  font-size: 1rem;
  font-weight: 700;
  color: var(--rust);
  margin-bottom: 0.75rem;
}

/* ─── Footer ─────────────────────────────────────────────────── */
.site-footer {
  background: var(--dark);
  color: var(--tan);
  padding: 3rem 1.25rem 2rem;
  margin-top: 4rem;
}
.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.75rem;
}
@media (min-width: 768px) {
  .footer-inner {
    grid-template-columns: auto 1fr auto;
    align-items: start;
  }
}
.footer-brand {
  font-size: 1.1rem;
  font-weight: 900;
  text-transform: uppercase;
  color: var(--white);
  letter-spacing: -0.3px;
}
.footer-brand span { color: var(--rust); }
.footer-tagline {
  display: block;
  font-size: 0.8rem;
  font-weight: 400;
  color: var(--tan);
  opacity: 0.6;
  margin-top: 0.35rem;
  text-transform: none;
  letter-spacing: 0;
}
.footer-links {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1.5rem;
  align-items: center;
}
.footer-links a { color: var(--tan); font-size: 0.875rem; transition: color 0.15s; }
.footer-links a:hover { color: var(--rust); text-decoration: none; }
.footer-copy {
  font-size: 0.78rem;
  color: var(--tan);
  opacity: 0.45;
  white-space: nowrap;
  align-self: end;
}
.footer-credit {
  background: rgba(10, 8, 4, 0.6);
  border: 1px solid rgba(212, 184, 150, 0.12);
  border-radius: 6px;
  max-width: 1100px;
  margin: 1.5rem auto 0;
  padding: 0.65rem 1.25rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem 1rem;
}
.footer-credit-left,
.footer-credit-right {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.4rem 0.6rem;
}
.footer-credit-label,
.footer-credit-tagline {
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--tan);
  opacity: 0.5;
}
.footer-credit-name {
  font-size: 0.9rem;
  font-weight: 900;
  color: var(--white);
  text-decoration: none;
  transition: color 0.15s;
}
.footer-credit-name:hover { color: var(--rust); text-decoration: none; }
.footer-credit-url {
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--tan);
  opacity: 0.65;
  text-decoration: none;
  transition: color 0.15s, opacity 0.15s;
}
.footer-credit-url:hover { color: var(--rust); opacity: 1; text-decoration: none; }

/* ─── Page header (non-hero pages) ──────────────────────────── */
.page-header {
  background: var(--dark);
  color: var(--white);
  padding: 3.5rem 1.25rem 3rem;
}
.page-header-inner { max-width: 1100px; margin: 0 auto; }
.page-header h1 { font-size: clamp(1.8rem, 5vw, 2.8rem); font-weight: 900; letter-spacing: -1px; }
.page-header p { color: var(--tan); margin-top: 0.6rem; font-size: 1rem; max-width: 560px; opacity: 0.85; }

/* ─── Category divider ───────────────────────────────────────── */
.category-heading {
  font-size: 1.15rem;
  font-weight: 900;
  text-transform: uppercase;
  color: var(--brown);
  letter-spacing: 0.06em;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--tan);
  margin: 3rem 0 1.5rem;
}
.category-heading:first-child { margin-top: 0; }

/* ─── Tire Pressure Calculator ───────────────────────────────── */
.calc-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  max-width: 920px;
  margin: 0 auto;
  padding: 2.5rem 1.25rem;
  align-items: start;
}
@media (min-width: 768px) { .calc-layout { grid-template-columns: 1fr 1fr; } }

.calc-panel {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.75rem;
}
.calc-panel h2 {
  font-size: 0.8rem;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--brown);
  margin-bottom: 1.5rem;
}
.form-group { margin-bottom: 1.25rem; }
.form-group label {
  display: block;
  font-weight: 600;
  font-size: 0.85rem;
  margin-bottom: 0.4rem;
  color: var(--brown);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.form-group input[type="number"],
.form-group select {
  width: 100%;
  padding: 0.6rem 0.8rem;
  border: 1.5px solid var(--tan);
  border-radius: 6px;
  font-size: 1rem;
  background: var(--sand);
  color: var(--text);
  font-family: var(--font);
  appearance: auto;
}
.form-group input[type="number"]:focus,
.form-group select:focus { outline: none; border-color: var(--rust); }

.radio-group { display: flex; flex-direction: column; gap: 0.45rem; }
.radio-option {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  cursor: pointer;
  font-size: 0.9rem;
  padding: 0.3rem 0;
}
.radio-option input { accent-color: var(--rust); width: 1rem; height: 1rem; cursor: pointer; }

.toggle-group { display: flex; gap: 0.5rem; }
.toggle-btn {
  flex: 1;
  padding: 0.55rem 0.5rem;
  border: 1.5px solid var(--tan);
  border-radius: 6px;
  background: var(--sand);
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--brown);
  font-family: var(--font);
  transition: all 0.15s;
  text-align: center;
}
.toggle-btn:hover { border-color: var(--rust); color: var(--rust); }
.toggle-btn.active { background: var(--rust); border-color: var(--rust); color: var(--white); }

/* Result panel */
.result-panel {
  background: var(--dark);
  color: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  min-height: 320px;
}
.result-panel h2 {
  font-size: 0.8rem;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--tan);
  margin-bottom: 1.5rem;
  opacity: 0.7;
}
.psi-row {
  display: flex;
  justify-content: space-around;
  margin-bottom: 1.75rem;
}
.psi-value { text-align: center; }
.psi-label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--tan);
  opacity: 0.7;
  margin-bottom: 0.3rem;
}
.psi-number { font-size: 3rem; font-weight: 900; color: var(--rust); line-height: 1; }
.psi-unit   { font-size: 0.8rem; color: var(--tan); opacity: 0.7; margin-top: 0.15rem; }
.psi-range  { font-size: 0.78rem; color: rgba(255,255,255,0.35); margin-top: 0.25rem; }

.result-explanation {
  font-size: 0.875rem;
  color: var(--tan);
  line-height: 1.65;
  opacity: 0.85;
  border-top: 1px solid rgba(255,255,255,0.08);
  padding-top: 1.25rem;
  margin-top: auto;
}
.result-placeholder {
  color: var(--tan);
  opacity: 0.3;
  font-size: 0.9rem;
  text-align: center;
  margin: auto;
  line-height: 1.7;
}

.calc-disclaimer {
  max-width: 920px;
  margin: 0 auto;
  padding: 0 1.25rem 2.5rem;
  font-size: 0.8rem;
  color: var(--brown);
  opacity: 0.7;
  line-height: 1.6;
}

/* ─── Blog article ───────────────────────────────────────────── */
.post-header {
  background: var(--dark);
  color: var(--white);
  padding: 4rem 1.25rem 3.5rem;
}
.post-header-inner { max-width: 760px; margin: 0 auto; }
.post-header .card-tag { margin-bottom: 1rem; background: var(--rust); }
.post-header h1 {
  font-size: clamp(1.8rem, 5vw, 2.8rem);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -1px;
  margin-bottom: 0.75rem;
}
.post-meta { color: var(--tan); font-size: 0.875rem; opacity: 0.7; }

.post-layout {
  max-width: 1080px;
  margin: 0 auto;
  padding: 2.5rem 1.25rem 4rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  align-items: start;
}
@media (min-width: 900px) { .post-layout { grid-template-columns: 1fr 240px; } }

.post-content { max-width: 720px; }
.post-content h2 { font-size: 1.4rem; font-weight: 800; color: var(--brown); margin: 2.5rem 0 0.75rem; padding-top: 0.5rem; border-top: 2px solid var(--tan); }
.post-content h3 { font-size: 1.05rem; font-weight: 700; color: var(--rust); margin: 1.5rem 0 0.5rem; }
.post-content p { margin-bottom: 1rem; }
.post-content ul, .post-content ol { padding-left: 1.5rem; margin-bottom: 1rem; }
.post-content li { margin-bottom: 0.45rem; }
.post-content strong { color: var(--brown); }
.post-content a { color: var(--rust); }

.post-toc {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.25rem 1.4rem;
  position: sticky;
  top: 78px;
}
.post-toc-title {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--brown);
  margin-bottom: 0.75rem;
  font-weight: 900;
}
.post-toc ol { padding-left: 1.1rem; }
.post-toc li { margin-bottom: 0.5rem; }
.post-toc a { font-size: 0.875rem; color: var(--text); transition: color 0.15s; }
.post-toc a:hover { color: var(--rust); text-decoration: none; }