/* tokens.css
   Design tokens + site styles for claude-skills-system.
   This file dogfoods the design-system-anti-slop skill: every color, space,
   radius, and shadow is a named token, consumed via var(). One accent, off-white
   and off-black (never pure), AA contrast, dark mode with equal hierarchy. */

:root {
  /* raw palette */
  --brand-600: #2563eb; /* single accent: a real blue, not AI-purple */
  --brand-700: #1d4ed8;
  --neutral-50: #fafaf9;
  --neutral-200: #e7e5e4;
  --neutral-400: #a8a29e;
  --neutral-600: #57534e;
  --neutral-900: #1c1c1e;

  /* semantic */
  --color-bg: #faf9f7;          /* off-white, not #fff */
  --color-surface: #ffffff;
  --color-text: #1c1c1e;        /* off-black, not #000 */
  --color-text-muted: #57534e;
  --color-border: #e7e5e4;
  --color-primary: var(--brand-600);
  --color-primary-hover: var(--brand-700);
  --color-on-primary: #ffffff;
  --color-success: #15803d;
  --color-warning: #b45309;

  /* typography */
  --font-sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "Cascadia Code", monospace;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.25rem;
  --text-xl: 1.6rem;
  --text-2xl: 2.25rem;
  --text-3xl: 3rem;
  --leading: 1.6;

  /* spacing scale */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-6: 24px;
  --space-8: 32px;
  --space-12: 48px;
  --space-16: 64px;
  --space-24: 96px;

  /* radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  /* elevation (used sparingly) */
  --elevation-1: 0 1px 2px rgb(0 0 0 / 0.05), 0 1px 3px rgb(0 0 0 / 0.08);
  --elevation-2: 0 4px 12px rgb(0 0 0 / 0.10);

  /* border + motion + layout */
  --border: 1px solid var(--color-border);
  --motion-fast: 120ms;
  --ease: cubic-bezier(0.2, 0, 0, 1);
  --maxw: 1080px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #0f1115;        /* off-black, not #000 */
    --color-surface: #16181d;
    --color-text: #e8e8ea;      /* off-white, not #fff */
    --color-text-muted: #9aa0a6;
    --color-border: #2a2d34;
    --brand-600: #5b8cff;       /* lifted for AA on dark */
    --brand-700: #7aa2ff;
    --color-success: #4ade80;
    --color-warning: #fbbf24;
    --elevation-1: 0 1px 2px rgb(0 0 0 / 0.5);
    --elevation-2: 0 6px 18px rgb(0 0 0 / 0.55);
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading);
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

a { color: var(--color-primary); text-decoration: none; }
a:hover { color: var(--color-primary-hover); text-decoration: underline; }

.wrap { max-width: var(--maxw); margin-inline: auto; padding-inline: var(--space-6); }

/* header: single row, brand left, actions right */
.site-header {
  position: sticky; top: 0; z-index: 1100;
  background: color-mix(in srgb, var(--color-bg) 88%, transparent);
  backdrop-filter: saturate(1.1) blur(6px);
  border-bottom: var(--border);
}
.site-header .wrap {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px; gap: var(--space-4);
}
.brand { font-weight: 700; letter-spacing: -0.01em; color: var(--color-text); }
.brand span { color: var(--color-primary); }
.nav { display: flex; gap: var(--space-6); align-items: center; }
.nav a { color: var(--color-text-muted); font-size: var(--text-sm); }
.nav a:hover { color: var(--color-text); text-decoration: none; }

/* buttons */
.btn {
  display: inline-flex; align-items: center; gap: var(--space-2);
  font-weight: 600; font-size: var(--text-sm);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md); border: var(--border);
  background: var(--color-surface); color: var(--color-text);
  cursor: pointer; transition: background var(--motion-fast) var(--ease), border-color var(--motion-fast) var(--ease);
}
.btn:hover { border-color: var(--color-primary); text-decoration: none; }
.btn:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 2px; }
.btn-primary { background: var(--color-primary); color: var(--color-on-primary); border-color: transparent; }
.btn-primary:hover { background: var(--color-primary-hover); color: var(--color-on-primary); }

/* hero: headline <= 2 lines, one subline, CTA above the fold */
.hero { padding-block: var(--space-24) var(--space-16); }
.hero h1 {
  font-size: clamp(2rem, 5vw, var(--text-3xl));
  line-height: 1.1; letter-spacing: -0.02em; margin: 0 0 var(--space-4);
  max-width: 16ch;
}
.hero p.lede {
  font-size: var(--text-lg); color: var(--color-text-muted);
  max-width: 56ch; margin: 0 0 var(--space-8);
}
.hero .actions { display: flex; gap: var(--space-3); flex-wrap: wrap; }

/* sections */
section { padding-block: var(--space-16); border-top: var(--border); }
.section-label { font-size: var(--text-sm); font-weight: 600; color: var(--color-primary); margin: 0 0 var(--space-2); }
h2 { font-size: var(--text-2xl); letter-spacing: -0.01em; margin: 0 0 var(--space-6); }
h3 { font-size: var(--text-lg); margin: 0 0 var(--space-2); }
.muted { color: var(--color-text-muted); }

/* skills: asymmetric, real content, not three decorative equal cards */
.skills { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); }
.skill {
  background: var(--color-surface); border: var(--border);
  border-radius: var(--radius-lg); padding: var(--space-6);
  display: flex; flex-direction: column; gap: var(--space-3);
}
.skill.feature { grid-column: 1 / -1; box-shadow: var(--elevation-1); }
.skill .top { display: flex; align-items: center; justify-content: space-between; gap: var(--space-3); }
.skill code { font-family: var(--font-mono); font-size: var(--text-sm); color: var(--color-text); }
.tier {
  font-size: 0.75rem; font-weight: 600; padding: 2px var(--space-2);
  border-radius: var(--radius-sm); border: var(--border); color: var(--color-text-muted);
}
.tier[data-tier="hard"] { color: var(--color-warning); border-color: color-mix(in srgb, var(--color-warning) 40%, var(--color-border)); }
.tags { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-top: auto; }
.tag { font-size: 0.75rem; color: var(--color-text-muted); background: var(--color-bg); border: var(--border); border-radius: var(--radius-sm); padding: 1px var(--space-2); }

/* code block */
pre {
  background: var(--color-surface); border: var(--border); border-radius: var(--radius-md);
  padding: var(--space-4); overflow-x: auto; font-family: var(--font-mono); font-size: var(--text-sm);
}
.copy-row { display: flex; gap: var(--space-3); align-items: center; margin-top: var(--space-3); }

/* footer: minimal, no version/build noise */
footer { border-top: var(--border); padding-block: var(--space-8); color: var(--color-text-muted); font-size: var(--text-sm); }
footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: var(--space-3); }

/* mobile: real reflow, not a shrunk desktop */
@media (max-width: 720px) {
  .nav { gap: var(--space-4); }
  .nav .hide-sm { display: none; }
  .skills { grid-template-columns: 1fr; }
  .hero { padding-block: var(--space-16) var(--space-12); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}