/* ==========================================================================
   SteelWorks — components.css
   THE SINGLE SOURCE. Every page derives from this file. No page-local custom
   properties, no inline colour. The web excellence gate enforces both.

   Derived from data/org/design-knowledge, cited per decision in
   data/org/web-design-decisions.md:
     style-systems.csv#4 Brutalism  +  #1 Minimalism & Swiss Style
     font-pairings.csv#9 "Developer Mono" — JetBrains Mono + IBM Plex Sans
     palettes.csv#81 (neutral direction; chromatics moved off the AI-default slate)
     motion-presets.csv#1,#2 hover micro-interaction · #4,#5 scroll reveal
                       #7,#8 stagger list
     ux-guidelines.csv — reduced motion, focus visibility, target sizing
     vendor/huashu-design/references/design-styles.md:31 — oklch convergence
   ========================================================================== */

/* --- tokens --------------------------------------------------------------
   huashu rule: 2–3 chromatic + ONE neutral set written as a lightness
   sequence. Chromatic hues 150° apart (rule asks >=60°). The previous site
   had two blues ~15° apart — one hue pretending to be two.                */
:root {
  /* neutral ramp — oklch lightness sequence */
  --ink-900: oklch(0.15 0.02  250);   /* page ground            */
  --ink-700: oklch(0.28 0.02  250);   /* raised surface         */
  --ink-500: oklch(0.45 0.015 250);   /* borders, rules         */
  --ink-300: oklch(0.72 0.01  250);   /* secondary text         */
  --ink-100: oklch(0.95 0.005 250);   /* primary text           */

  /* chromatics — exactly two */
  --signal:  oklch(0.78 0.16   75);   /* amber: CTA, receipt accent */
  --signal-ink: oklch(0.15 0.02 250); /* text ON signal             */
  --link:    oklch(0.70 0.12  225);   /* cyan: links, informational */

  /* type */
  --font-display: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --font-body: "IBM Plex Sans", system-ui, -apple-system, sans-serif;

  /* swiss grid + rhythm */
  --measure: 68ch;
  --gutter: clamp(1rem, 3vw, 2.5rem);
  --shell: 72rem;
  --step--1: clamp(0.83rem, 0.8rem + 0.15vw, 0.9rem);
  --step-0:  clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --step-1:  clamp(1.35rem, 1.2rem + 0.7vw, 1.75rem);
  --step-2:  clamp(1.8rem, 1.5rem + 1.5vw, 2.75rem);
  --step-3:  clamp(2.4rem, 1.8rem + 3vw, 4rem);

  /* motion — motion-presets.csv durations, not invented */
  --dur-hover: 180ms;   /* #1 subtle hover 150–200ms */
  --dur-reveal: 420ms;  /* #5 standard scroll reveal 400–600ms */
  --ease: cubic-bezier(0.2, 0, 0, 1);
}

/* --- reset ---------------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--ink-900);
  color: var(--ink-100);
  font-family: var(--font-body);
  font-size: var(--step-0);
  line-height: 1.6;
  text-wrap: pretty;            /* huashu README:248 */
}
img, svg, video { max-width: 100%; height: auto; display: block; }

/* --- type ----------------------------------------------------------------- */
h1, h2, h3, .display {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  text-wrap: balance;
  margin: 0 0 0.5em;
}
h1 { font-size: var(--step-3); }
h2 { font-size: var(--step-2); }
h3 { font-size: var(--step-1); }
p  { max-width: var(--measure); margin: 0 0 1em; }
.mono, code, kbd, .metric { font-family: var(--font-display); }
.eyebrow {
  font-family: var(--font-display);
  font-size: var(--step--1);
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--signal);
  margin: 0 0 0.75rem;
}
.lede { font-size: var(--step-1); color: var(--ink-300); }
a { color: var(--link); text-underline-offset: 0.2em; }
a:hover { color: var(--ink-100); }

/* --- layout: swiss grid ---------------------------------------------------- */
.shell { width: min(100% - (var(--gutter) * 2), var(--shell)); margin-inline: auto; }
.section { padding-block: clamp(3rem, 8vw, 6rem); }
.grid { display: grid; gap: var(--gutter); }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 20rem), 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 15rem), 1fr)); }
.rule { border: 0; border-top: 1px solid var(--ink-500); margin: 0; }

/* --- icons: Tabler, locked non-default configuration ----------------------
   stroke 1.5 (not the 2 default), butt caps + miter joins = square terminals
   matching the mono/receipt identity. Monochrome, inherits currentColor.   */
.ti {
  width: 1.25em; height: 1.25em;
  stroke: currentColor;
  stroke-width: 1.5;
  stroke-linecap: butt;
  stroke-linejoin: miter;
  fill: none;
  flex: none;
  vertical-align: -0.2em;
}
.ti-lg { width: 2rem; height: 2rem; }

/* --- shell: header / nav / footer ------------------------------------------ */
.site-header {
  border-bottom: 1px solid var(--ink-500);
  background: var(--ink-900);
  position: sticky; top: 0; z-index: 10;
}
.site-header .shell {
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--gutter); padding-block: 1rem;
}
.brand {
  font-family: var(--font-display); font-weight: 700; letter-spacing: -0.03em;
  color: var(--ink-100); text-decoration: none; display: inline-flex;
  align-items: center; gap: 0.5rem;
}
.brand .ti { color: var(--signal); }
.site-nav { display: flex; gap: 1.5rem; align-items: center; }
.site-nav a {
  font-family: var(--font-display); font-size: var(--step--1);
  color: var(--ink-300); text-decoration: none;
  transition: color var(--dur-hover) var(--ease);
}
.site-nav a:hover, .site-nav a[aria-current="page"] { color: var(--ink-100); }
.site-footer {
  border-top: 1px solid var(--ink-500);
  padding-block: 3rem; margin-top: 4rem; color: var(--ink-300);
  font-size: var(--step--1);
}
.site-footer .shell { display: grid; gap: 1.5rem; }
.footer-links { display: flex; flex-wrap: wrap; gap: 1.25rem; }
.footer-links a { color: var(--ink-300); text-decoration: none; }
.footer-links a:hover { color: var(--ink-100); }

/* --- buttons / CTA --------------------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  font-family: var(--font-display); font-weight: 700; font-size: var(--step-0);
  padding: 0.85rem 1.4rem;
  min-height: 44px;                       /* ux-guidelines: target size */
  border: 1px solid var(--signal);
  background: var(--signal); color: var(--signal-ink);
  text-decoration: none; cursor: pointer;
  transition: transform var(--dur-hover) var(--ease),
              background var(--dur-hover) var(--ease);
}
.btn:hover { transform: translateY(-2px); color: var(--signal-ink); }
.btn:active { transform: translateY(0); }
.btn-ghost { background: transparent; color: var(--ink-100); border-color: var(--ink-500); }
.btn-ghost:hover { border-color: var(--ink-100); color: var(--ink-100); }
:where(a, button, input, select, textarea):focus-visible {
  outline: 2px solid var(--signal); outline-offset: 3px;   /* ux-guidelines */
}

/* --- cards / surfaces ------------------------------------------------------ */
.card {
  background: var(--ink-700);
  border: 1px solid var(--ink-500);
  padding: var(--gutter);
  /* brutalist: square corners, no soft shadow — style-systems.csv#4.
     huashu README:248 names "rounded corners + left border accent" an AI tell. */
}
.card h3 { margin-top: 0; }
.card .ti { color: var(--signal); }
.metric { font-size: var(--step-2); color: var(--signal); display: block; }
.receipt {
  font-family: var(--font-display); font-size: var(--step--1);
  border: 1px dashed var(--ink-500); padding: var(--gutter);
  background: color-mix(in oklch, var(--ink-700) 60%, transparent);
}
.receipt dl { display: grid; grid-template-columns: 1fr auto; gap: 0.4rem 1rem; margin: 0; }
.receipt dt { color: var(--ink-300); }
.receipt dd { margin: 0; text-align: right; }

/* --- forms (capture) ------------------------------------------------------- */
.capture { display: flex; flex-wrap: wrap; gap: 0.75rem; }
.capture input[type="email"] {
  flex: 1 1 16rem; min-height: 44px; padding: 0.75rem 1rem;
  font-family: var(--font-body); font-size: var(--step-0);
  background: var(--ink-900); color: var(--ink-100);
  border: 1px solid var(--ink-500);
}
.capture input::placeholder { color: var(--ink-300); }

/* --- motion: CSS scroll-driven, zero JS -----------------------------------
   motion-presets.csv#5 scroll reveal (400–600ms) and #7 stagger list.
   The site had ZERO motion before this program.                           */
@keyframes reveal {
  from { opacity: 0.001; transform: translateY(1.25rem); }
  to   { opacity: 1; transform: none; }
}
/* CONTENT MUST NEVER BE HIDDEN BY DECORATION.
   First version used `animation-range: entry 10% cover 32%`. Measured in a real
   browser: of the .reveal elements scrolled INTO view, 2 of 4 were still at
   opacity < 0.5 — the range had not been crossed, so the `both` fill held the
   from-state and the copy stayed invisible. A full-page screenshot showed most of
   the page as blank black. Decoration that can permanently hide content is a
   defect, not a style choice.
   The range now completes while the element is still entering, so anything on
   screen is legible, and `reveal` starts from 0.001 rather than 0 so a stalled
   timeline degrades to "faint" rather than "gone". */
@supports (animation-timeline: view()) {
  .reveal {
    animation: reveal var(--dur-reveal) var(--ease) both;
    animation-timeline: view();
    animation-range: entry 0% entry 75%;
  }
}
@supports not (animation-timeline: view()) {
  .reveal { animation: reveal var(--dur-reveal) var(--ease) both; }
}
.stagger > * { animation-delay: calc(var(--i, 0) * 70ms); }

/* ux-guidelines.csv — accessibility. Motion is decoration; it must be optional. */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .reveal { animation: none; opacity: 1; transform: none; }
}

/* --- utilities ------------------------------------------------------------- */
.visually-hidden {
  position: absolute; width: 1px; height: 1px; overflow: hidden;
  clip-path: inset(50%); white-space: nowrap;
}
.skip-link {
  position: absolute; left: 0; top: -3rem; background: var(--signal);
  color: var(--signal-ink); padding: 0.6rem 1rem; z-index: 100;
  font-family: var(--font-display);
}
.skip-link:focus { top: 0; }
.stack > * + * { margin-top: var(--gutter); }
.cluster { display: flex; flex-wrap: wrap; gap: 0.75rem; align-items: center; }

/* Utilities that exist because the gate refused inline colour on real pages.
   Every one of these replaced a style="color:…" a page author would otherwise
   have written by hand — which is how 192 pages drift apart. */
.flush { margin: 0; }
.pad-t { padding-top: var(--gutter); }

/* Generated supporting figures are rendered at 512x384 (the resolution that made
   171 images take under an hour instead of 13). `max-width:100%` alone let them
   stretch to ~1060px in a wide shell — a 2x upscale that reads visibly soft and
   swallowed the viewport. Cap at native width and keep them left-aligned as
   supporting evidence rather than hero art. */
figure img { max-width: min(100%, 32rem); }
figure.hero img { max-width: 100%; }
.fine { font-family: var(--font-display); font-size: var(--step--1); color: var(--ink-300); }
figcaption.fine { padding-top: 0.75rem; }