/* =========================================
   Friction Lab — styles.css
   Shared stylesheet for frictionlab.dev
   ========================================= */

:root {
  /* Surfaces */
  --bg:           #f8f7f4;
  --surface:      #ffffff;
  --surface-alt:  #f0ede7;

  /* Borders */
  --border:       #e3dfd8;
  --border-strong:#c6c1b9;

  /* Text */
  --text-primary:   #1a1917;
  --text-secondary: #57534e;
  --text-muted:     #9c9790;

  /* Accent */
  --accent:        #4361ee;
  --accent-hover:  #3451d4;
  --accent-subtle: #eef0fd;
  --accent-border: rgba(67, 97, 238, 0.22);

  /* Grid overlay */
  --grid-line: rgba(67, 97, 238, 0.065);

  /* Status — Released RC */
  --rc-bg:     #dcfce7;
  --rc-text:   #14532d;
  --rc-border: #86efac;

  /* Status — In development */
  --dev-bg:     #fef9c3;
  --dev-text:   #713f12;
  --dev-border: #fde047;

  /* Status — Planned */
  --planned-bg:     #f3f4f6;
  --planned-text:   #374151;
  --planned-border: #d1d5db;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Cascadia Code', Menlo, monospace;

  /* Shape */
  --radius:    7px;
  --radius-sm: 4px;

  /* Layout */
  --max-w:  1080px;
  --nav-h:  58px;
}

/* ---- Reset ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}
img   { max-width: 100%; display: block; }
ul    { list-style: none; }
a     { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---- Container ---- */
.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

/* ==================
   Navigation
   ================== */
.site-nav {
  height: var(--nav-h);
  background: rgba(248, 247, 244, 0.94);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 200;
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav-brand {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.01em;
  flex-shrink: 0;
}
.nav-brand:hover { text-decoration: none; color: var(--accent); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 2px;
}
.nav-links a {
  font-size: 14px;
  color: var(--text-secondary);
  padding: 5px 11px;
  border-radius: var(--radius-sm);
  transition: color 0.12s, background 0.12s;
}
.nav-links a:hover {
  color: var(--text-primary);
  background: var(--surface-alt);
  text-decoration: none;
}
.nav-links a.active {
  color: var(--text-primary);
  font-weight: 500;
}
.nav-github {
  display: inline-flex !important;
  align-items: center;
  gap: 5px;
  border: 1px solid var(--border) !important;
  border-radius: var(--radius-sm) !important;
  padding: 4px 12px !important;
  font-size: 13px !important;
  margin-left: 6px;
  transition: border-color 0.12s;
}
.nav-github:hover { border-color: var(--border-strong) !important; }
.nav-github svg  { flex-shrink: 0; }

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  padding: 6px 9px;
  color: var(--text-primary);
  line-height: 1;
}

/* ==================
   Announcement Strip
   ================== */
.announce-strip {
  background: transparent;
  padding: 12px 0 0;
  text-align: center;
}
.announce-strip-inner {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-secondary);
  padding: 4px 16px;
  border: 1px solid var(--border);
  border-radius: 20px;
  background: var(--surface);
  text-decoration: none;
  transition: border-color 0.13s, color 0.13s, background 0.13s;
  line-height: 1;
}
.announce-strip-inner:hover {
  border-color: rgba(67, 97, 238, 0.35);
  background: var(--accent-subtle);
  color: var(--accent);
  text-decoration: none;
}
.announce-dot {
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #16a34a;
  flex-shrink: 0;
}

/* ==================
   Hero
   ================== */
.hero {
  padding: 96px 0 80px;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
}

/* Blueprint grid */
.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: 44px 44px;
  mask-image: radial-gradient(ellipse 85% 100% at 50% 0%, black 25%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 85% 100% at 50% 0%, black 25%, transparent 100%);
  pointer-events: none;
}

/* Corner bracket decorations */
.hero-corner {
  position: absolute;
  pointer-events: none;
  width: 18px;
  height: 18px;
  border-color: rgba(67, 97, 238, 0.18);
  border-style: solid;
}
.hero-corner.tl { top: 18px; left: 18px; border-width: 1px 0 0 1px; }
.hero-corner.tr { top: 18px; right: 18px; border-width: 1px 1px 0 0; }
.hero-corner.bl { bottom: 18px; left: 18px; border-width: 0 0 1px 1px; }
.hero-corner.br { bottom: 18px; right: 18px; border-width: 0 1px 1px 0; }

/* Background workflow-node diagram */
.hero-bg-diagram {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  color: var(--accent);
  opacity: 0.08;
  pointer-events: none;
  z-index: 0;
}

/* Side ruler tick marks */
.hero-ruler-left,
.hero-ruler-right {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 0;
  pointer-events: none;
  z-index: 0;
}
.hero-ruler-left  { left: 12px; }
.hero-ruler-right { right: 12px; }

.hero-ruler-left::before,
.hero-ruler-right::before {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  width: 1px;
  background: rgba(67, 97, 238, 0.09);
}
.hero-ruler-left::before  { left: 0; }
.hero-ruler-right::before { right: 0; }

.hero-ruler-left::after,
.hero-ruler-right::after {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  width: 6px;
  background-image: repeating-linear-gradient(
    to bottom,
    transparent 0px,
    transparent 17px,
    rgba(67, 97, 238, 0.13) 17px,
    rgba(67, 97, 238, 0.13) 18px
  );
}
.hero-ruler-left::after  { left: 1px; }
.hero-ruler-right::after { right: 1px; }

/* Engineering label decorations */
.hero-dec {
  position: absolute;
  pointer-events: none;
  font-family: var(--font-mono);
  font-size: 10px;
  color: rgba(67, 97, 238, 0.28);
  letter-spacing: 0.06em;
  user-select: none;
}
.hero-dec.top-left  { top: 28px; left: 40px; }
.hero-dec.top-right { top: 28px; right: 40px; }

.hero-inner {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 700px;
  margin: 0 auto;
}
.hero-eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-subtle);
  border: 1px solid var(--accent-border);
  border-radius: 20px;
  padding: 4px 14px;
  margin-bottom: 26px;
}
.hero h1 {
  font-size: clamp(30px, 4.6vw, 50px);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.11;
  color: var(--text-primary);
  margin-bottom: 20px;
}
.hero-sub {
  font-size: 17px;
  line-height: 1.7;
  color: var(--text-secondary);
  max-width: 540px;
  margin: 0 auto 36px;
}
.hero-actions {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ==================
   Buttons
   ================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 18px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.12s, border-color 0.12s, color 0.12s;
  text-decoration: none;
  border: 1px solid transparent;
}
.btn:hover { text-decoration: none; }
.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.btn-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); }
.btn-secondary {
  background: var(--surface);
  color: var(--text-primary);
  border-color: var(--border-strong);
}
.btn-secondary:hover { background: var(--surface-alt); }

/* ==================
   Sections
   ================== */
.section { padding: 68px 0; }
.section + .section { border-top: 1px solid var(--border); }

.section-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 10px;
}
.section-title {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: 10px;
}
.section-sub {
  font-size: 16px;
  color: var(--text-secondary);
  max-width: 500px;
  margin-bottom: 44px;
  line-height: 1.65;
}

/* ==================
   Status Pills
   ================== */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.01em;
  padding: 3px 9px;
  border-radius: 20px;
  white-space: nowrap;
  flex-shrink: 0;
}
.pill::before {
  content: '';
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: currentColor;
  opacity: 0.75;
}
.pill-rc      { background: var(--rc-bg);      color: var(--rc-text);      border: 1px solid var(--rc-border); }
.pill-dev     { background: var(--dev-bg);     color: var(--dev-text);     border: 1px solid var(--dev-border); }
.pill-planned { background: var(--planned-bg); color: var(--planned-text); border: 1px solid var(--planned-border); }

/* ==================
   Principle Cards
   ================== */
.principles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.principle-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px 22px;
}
.principle-icon {
  width: 34px;
  height: 34px;
  background: var(--accent-subtle);
  border: 1px solid var(--accent-border);
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
}
.principle-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.01em;
  margin-bottom: 7px;
}
.principle-desc {
  font-size: 14px;
  line-height: 1.65;
  color: var(--text-secondary);
}

/* ==================
   Product Cards (home)
   ================== */
.product-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}
.product-grid-minor {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 16px;
}
.product-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  display: flex;
  flex-direction: column;
  gap: 13px;
  transition: border-color 0.12s;
}
.product-card:hover { border-color: var(--border-strong); }

/* Featured (released) card gets a subtle accent tint */
.product-card.featured {
  border-color: var(--accent-border);
}
.product-card.featured:hover { border-color: rgba(67, 97, 238, 0.36); }

.card-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 10px;
}
.product-name {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}
.product-desc {
  font-size: 14px;
  line-height: 1.65;
  color: var(--text-secondary);
  flex: 1;
}
.product-note {
  font-size: 12px;
  color: var(--text-muted);
  padding: 8px 10px;
  background: var(--surface-alt);
  border-left: 2px solid var(--border-strong);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  line-height: 1.55;
}
.product-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
}
.tag {
  font-family: var(--font-mono);
  font-size: 10px;
  color: #3a4a72;
  background: #eaecf9;
  border: 1px solid #c0cae8;
  border-radius: 3px;
  padding: 2px 7px;
}
.product-links {
  display: flex;
  gap: 14px;
  align-items: center;
  flex-wrap: wrap;
  margin-top: auto;
}
.product-link { font-size: 13px; color: var(--accent); font-weight: 500; }
.product-link:hover { color: var(--accent-hover); }
.product-link-muted { font-size: 12px; color: var(--text-muted); font-style: italic; }

/* ==================
   Toolchain Band
   ================== */
.toolchain-band {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 22px 0 26px;
}
.toolchain-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  text-align: center;
  margin-bottom: 20px;
}
.toolchain-track {
  position: relative;
  overflow-x: auto;
  padding-bottom: 2px;
}
.toolchain-track-line {
  position: absolute;
  top: 9px;
  left: 8%;
  right: 8%;
  height: 1px;
  background: var(--border);
  pointer-events: none;
}
.toolchain-nodes {
  display: flex;
  justify-content: center;
  gap: 0;
  min-width: 480px;
  padding-top: 4px;
}
.toolchain-node {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  flex: 1;
  padding: 0 8px;
}
.tc-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 1.5px solid var(--border-strong);
  background: var(--surface);
  position: relative;
  z-index: 1;
  flex-shrink: 0;
}
.toolchain-node.tc-released .tc-dot {
  border-color: var(--accent);
  background: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-subtle);
}
.tc-name {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}
.tc-type {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--text-muted);
  letter-spacing: 0.03em;
}

/* ==================
   Products Page — Detail Cards
   ================== */
.product-detail-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  transition: border-color 0.12s;
}
.product-detail-card + .product-detail-card { margin-top: 16px; }
.product-detail-card:hover { border-color: var(--border-strong); }
.product-detail-card.featured { border-color: var(--accent-border); }
.product-detail-card.featured:hover { border-color: rgba(67, 97, 238, 0.38); }

.product-detail-head {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}
.product-detail-name {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}
.product-detail-desc {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-secondary);
}
.product-detail-note {
  font-size: 13px;
  color: var(--text-muted);
  padding: 10px 14px;
  background: var(--surface-alt);
  border-left: 2px solid var(--border-strong);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  line-height: 1.6;
}

/* ==================
   Page Hero (inner pages)
   ================== */
.page-hero {
  padding: 52px 0 44px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}
.page-eyebrow {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 10px;
}
.page-hero h1 {
  font-size: 34px;
  font-weight: 700;
  letter-spacing: -0.025em;
  color: var(--text-primary);
  margin-bottom: 10px;
}
.page-hero-sub {
  font-size: 16px;
  color: var(--text-secondary);
  max-width: 520px;
  line-height: 1.65;
}

/* ==================
   Blog
   ================== */
.blog-list { display: flex; flex-direction: column; }
.blog-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 8px;
  transition: border-color 0.12s;
}
.blog-item:hover { border-color: var(--border-strong); }
.blog-item-title {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 4px;
}
.blog-item-topic {
  font-size: 13px;
  color: var(--text-muted);
  font-family: var(--font-mono);
}
.badge-soon {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 600;
  color: var(--text-muted);
  background: var(--surface-alt);
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 3px 9px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  white-space: nowrap;
}

/* ==================
   About
   ================== */
.about-layout {
  display: grid;
  grid-template-columns: 1.65fr 1fr;
  gap: 56px;
  align-items: start;
}
.about-content p {
  font-size: 16px;
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 16px;
}
.about-content p:last-child { margin-bottom: 0; }
.about-sidebar-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 14px;
}
.values-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 32px;
}
.values-list li {
  display: flex;
  align-items: flex-start;
  gap: 9px;
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.5;
}
.values-list li::before {
  content: '—';
  color: var(--accent);
  font-family: var(--font-mono);
  flex-shrink: 0;
  margin-top: 1px;
}
.contact-block { margin-top: 36px; }
.contact-block p { font-size: 14px; color: var(--text-secondary); margin-bottom: 6px; }
.contact-block a { color: var(--accent); }

/* ==================
   Footer
   ================== */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--surface);
  padding: 28px 0;
}
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}
.footer-brand {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary);
}
.footer-links { display: flex; gap: 18px; }
.footer-links a { font-size: 13px; color: var(--text-muted); transition: color 0.12s; }
.footer-links a:hover { color: var(--text-primary); text-decoration: none; }
.footer-meta {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-muted);
  text-align: right;
}

/* ==================
   Utilities
   ================== */
.mono { font-family: var(--font-mono); }
.text-muted { color: var(--text-muted); }

/* ==================
   Responsive
   ================== */
@media (max-width: 800px) {
  .principles-grid           { grid-template-columns: 1fr; gap: 14px; }
  .product-grid              { grid-template-columns: 1fr; }
  .product-grid-minor        { grid-template-columns: 1fr; }
  .about-layout              { grid-template-columns: 1fr; gap: 36px; }

  /* Mobile nav */
  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-h);
    left: 0; right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    align-items: flex-start;
    padding: 14px 20px;
    gap: 2px;
  }
  .nav-links.open { display: flex; }
  .site-nav  { position: relative; }
  .nav-toggle { display: block; }
  .nav-github { margin-left: 0 !important; }

  .hero { padding: 60px 0 52px; }
  .hero-dec { display: none; }
  .hero-corner { display: none; }
  .hero-ruler-left { display: none; }
  .hero-ruler-right { display: none; }
  .hero-bg-diagram { opacity: 0.04; }

  .blog-item { flex-direction: column; align-items: flex-start; }
  .footer-inner { flex-direction: column; text-align: center; }
  .footer-links { justify-content: center; }
  .footer-meta  { text-align: center; }
}

@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .hero-actions { flex-direction: column; align-items: center; }
  .section { padding: 52px 0; }
  .page-hero { padding: 36px 0 30px; }
  .page-hero h1 { font-size: 26px; }
  .section-title { font-size: 22px; }
  .announce-strip-inner { font-size: 11px; padding: 4px 12px; }
}