/* ==========================================================================
   base.css — infracontext.net
   Direction: Technical-craft / engineered-calm (sysinit design language)
   Signal: green tint (vs sysinit's red)
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. Tokens — light
   -------------------------------------------------------------------------- */

:root {
  --font-sans: "Inter Tight", -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", Consolas, monospace;

  --paper:        #ffffff;
  --paper-2:      #f6f6f6;
  --paper-3:      #ebebeb;
  --line:         #e1e1e1;
  --line-strong:  #b3b3b3;

  --ink:          #111111;
  --ink-2:        #383838;
  --ink-3:        #6a6a6a;
  --ink-4:        #989898;

  /* Signal — deep engineered green (replaces sysinit's #D6391C red) */
  --signal:       #1c7a3e;
  --signal-ink:   #0d4d27;
  --signal-soft:  #dceee2;

  --header-bg:    rgba(255, 255, 255, 0.85);

  --t-xxs: 11px;
  --t-xs:  12px;
  --t-sm:  14px;
  --t-base:16px;
  --t-md:  18px;
  --t-lg:  22px;
  --t-xl:  28px;
  --t-2xl: 36px;
  --t-3xl: 48px;
  --t-4xl: 64px;
  --t-5xl: 88px;

  --s-1:  4px;
  --s-2:  8px;
  --s-3:  12px;
  --s-4:  16px;
  --s-5:  24px;
  --s-6:  32px;
  --s-7:  48px;
  --s-8:  64px;
  --s-9:  96px;
  --s-10: 128px;

  --r-1: 2px;
  --r-2: 4px;
  --r-3: 6px;

  --gutter: 24px;
  --container: 1200px;
}

/* --------------------------------------------------------------------------
   2. Tokens — dark
   -------------------------------------------------------------------------- */

[data-theme="dark"] {
  --paper:        #0e0d0a;
  --paper-2:      #1a1814;
  --paper-3:      #26231d;
  --line:         #2f2c25;
  --line-strong:  #4a463c;

  --ink:          #f3efe7;
  --ink-2:        #c9c4b6;
  --ink-3:        #8e8a7e;
  --ink-4:        #5e5b51;

  --signal:       #4dd487;
  --signal-ink:   #72e3a3;
  --signal-soft:  #0f2a1a;

  --header-bg:    rgba(14, 13, 10, 0.85);
}

/* --------------------------------------------------------------------------
   3. Reset
   -------------------------------------------------------------------------- */

*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

body {
  font-family: var(--font-sans);
  font-size: var(--t-base);
  line-height: 1.55;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  font-feature-settings: "ss01", "cv11";
}

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

/* --------------------------------------------------------------------------
   4. Links
   -------------------------------------------------------------------------- */

a {
  color: var(--ink);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover { color: var(--signal); }

/* --------------------------------------------------------------------------
   5. Container
   -------------------------------------------------------------------------- */

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

/* --------------------------------------------------------------------------
   6. Type primitives
   -------------------------------------------------------------------------- */

.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--t-xxs);
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.eyebrow .num { color: var(--signal); }

.mono {
  font-family: var(--font-mono);
  font-size: 0.92em;
  letter-spacing: -0.005em;
}

.signal { color: var(--signal); }

/* --------------------------------------------------------------------------
   7. Header — wordmark + product lockup, GitHub link, theme toggle
   -------------------------------------------------------------------------- */

header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 72px;
  gap: var(--s-6);
}

/* Logo lockup: sysinit▍ | Infracontext */
.logo {
  display: inline-flex;
  align-items: baseline;
  gap: 10px;
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 22px;
  letter-spacing: -0.04em;
  line-height: 1;
  color: var(--ink);
  text-decoration: none;
}

.logo:hover { color: var(--ink); }

.logo-svg { display: none; }

.logo-text {
  display: inline-flex;
  align-items: baseline;
  color: var(--ink);
}

.logo-text::after {
  content: "";
  display: inline-block;
  width: 2px;
  height: 17px;
  background: var(--signal);
  margin-left: 2px;
  transform: translateY(2px);
}

.logo-divider {
  display: inline-block;
  width: 1px;
  height: 18px;
  background: var(--line-strong);
  transform: translateY(3px);
  font-size: 0;
  color: transparent;
}

.logo-product {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 18px;
  letter-spacing: -0.02em;
  color: var(--ink-2);
}

/* --------------------------------------------------------------------------
   8. Navigation
   -------------------------------------------------------------------------- */

nav ul {
  display: flex;
  list-style: none;
  gap: var(--s-6);
  margin: 0;
  padding: 0;
}

nav a {
  font-family: var(--font-mono);
  font-size: var(--t-xs);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--ink-2);
  font-weight: 500;
}

nav a:hover { color: var(--signal); }

.mobile-menu-btn {
  display: none;
  background: none;
  border: 0;
  font-size: 1.4rem;
  color: var(--ink);
  cursor: pointer;
  padding: 0;
}

/* --------------------------------------------------------------------------
   9. Header controls
   -------------------------------------------------------------------------- */

.header-controls {
  display: flex;
  align-items: center;
  gap: var(--s-3);
}

.github-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 12px;
  border: 1px solid var(--line-strong);
  border-radius: var(--r-2);
  font-family: var(--font-mono);
  font-size: var(--t-xs);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--ink);
  transition: border-color 0.15s ease, color 0.15s ease;
}

.github-link:hover {
  border-color: var(--ink);
  color: var(--ink);
}

.github-link svg {
  width: 14px;
  height: 14px;
  fill: currentColor;
}

.theme-toggle {
  background: none;
  border: 1px solid var(--line);
  border-radius: var(--r-2);
  cursor: pointer;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  color: var(--ink-2);
  position: relative;
  transition: border-color 0.15s ease;
}

.theme-toggle:hover { border-color: var(--ink); }

.sun-icon, .moon-icon {
  position: absolute;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.sun-icon { opacity: 0; transform: scale(0.6); }
.moon-icon { opacity: 1; transform: scale(1); }

[data-theme="dark"] .sun-icon { opacity: 1; transform: scale(1); }
[data-theme="dark"] .moon-icon { opacity: 0; transform: scale(0.6); }

/* --------------------------------------------------------------------------
   10. Section header (eyebrow + title)
   -------------------------------------------------------------------------- */

.section-header {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 48px;
  margin-bottom: var(--s-8);
  align-items: start;
  border-top: 1px solid var(--ink);
  padding-top: var(--s-7);
}

.section-header .label {
  font-family: var(--font-mono);
  font-size: var(--t-xs);
  letter-spacing: 0.08em;
  color: var(--ink-3);
}

.section-header .label .num {
  color: var(--signal);
  display: block;
  margin-bottom: 4px;
}

.section-header .label .name {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--ink-2);
}

.section-header h2 {
  font-family: var(--font-sans);
  font-size: clamp(36px, 5vw, 56px);
  line-height: 1.04;
  letter-spacing: -0.028em;
  font-weight: 600;
  margin: 0;
  color: var(--ink);
  text-wrap: balance;
}

.section-header p {
  font-family: var(--font-sans);
  font-size: var(--t-md);
  line-height: 1.5;
  color: var(--ink-2);
  margin: 16px 0 0;
  max-width: 60ch;
  text-wrap: pretty;
}

/* --------------------------------------------------------------------------
   11. Buttons
   -------------------------------------------------------------------------- */

.btn-primary,
.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: var(--s-2);
  padding: 12px 18px;
  font-family: var(--font-sans);
  font-size: var(--t-sm);
  font-weight: 500;
  letter-spacing: 0.005em;
  border-radius: var(--r-2);
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease;
  text-decoration: none;
  line-height: 1;
}

.btn-primary {
  background: var(--ink);
  color: var(--paper);
  border-color: var(--ink);
}
.btn-primary:hover {
  background: var(--signal);
  border-color: var(--signal);
  color: #fff;
}

.btn-secondary {
  background: transparent;
  color: var(--ink);
  border-color: var(--line-strong);
}
.btn-secondary:hover {
  background: var(--paper-2);
  border-color: var(--ink);
  color: var(--ink);
}

.btn-primary svg,
.btn-secondary svg {
  width: 14px;
  height: 14px;
}

/* --------------------------------------------------------------------------
   12. Tag / chip
   -------------------------------------------------------------------------- */

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px 4px 8px;
  font-family: var(--font-mono);
  font-size: var(--t-xxs);
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink-2);
  background: var(--paper-2);
  border: 1px solid var(--line);
  border-radius: var(--r-1);
}

.tag .dot {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--ink-3);
}

.tag-signal {
  color: var(--signal-ink);
  background: var(--signal-soft);
  border-color: transparent;
}
.tag-signal .dot { background: var(--signal); }

/* --------------------------------------------------------------------------
   13. Footer
   -------------------------------------------------------------------------- */

footer {
  background: var(--ink);
  color: var(--paper-2);
  padding: var(--s-7) 0 var(--s-5);
  margin-top: var(--s-9);
  border-top: 1px solid var(--ink);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--s-5);
}

.footer-links {
  display: flex;
  gap: var(--s-6);
}

.footer-links a {
  font-family: var(--font-mono);
  font-size: var(--t-xs);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--paper-3);
}

.footer-links a:hover { color: var(--signal); }

.footer-by {
  font-family: var(--font-mono);
  font-size: var(--t-xs);
  color: var(--ink-3);
  letter-spacing: 0.04em;
}

.footer-by a {
  color: var(--paper-3);
  border-bottom: 1px solid var(--ink-3);
}

.footer-by a:hover { color: var(--signal); border-color: var(--signal); }

/* --------------------------------------------------------------------------
   14. Reveal-on-scroll
   -------------------------------------------------------------------------- */

.reveal-on-scroll {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.reveal-on-scroll.revealed {
  opacity: 1;
  transform: translateY(0);
}

/* --------------------------------------------------------------------------
   15. Responsive
   -------------------------------------------------------------------------- */

@media (max-width: 900px) {
  .section-header {
    grid-template-columns: 1fr;
    gap: var(--s-4);
    padding-top: var(--s-6);
  }
  .section-header h2 { font-size: 36px; }
}

@media (max-width: 768px) {
  .header-content {
    position: relative;
    flex-wrap: wrap;
    height: auto;
    padding: 16px 0;
    gap: var(--s-3);
  }

  .mobile-menu-btn {
    display: block;
    order: 3;
  }

  .header-controls {
    order: 2;
    margin-left: auto;
  }

  .github-link span { display: none; }
  .github-link { padding: 7px 9px; }

  nav {
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    clip-path: polygon(0 0, 100% 0, 100% 0, 0 0);
    transition: clip-path 0.2s ease;
  }

  nav.active {
    clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%);
  }

  nav ul {
    flex-direction: column;
    padding: var(--s-5);
    gap: var(--s-4);
  }

  nav a { font-size: var(--t-sm); }

  .footer-content {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--s-4);
  }
  .footer-links { flex-wrap: wrap; gap: var(--s-4); }
}

/* --------------------------------------------------------------------------
   16. Reduced motion
   -------------------------------------------------------------------------- */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto !important; }
  .reveal-on-scroll {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
  .btn-primary, .btn-secondary, .github-link, a { transition: none !important; }
}