/*
 * AI CareerStack — Design System v1.0
 * Shared across all pages. Safe-to-add layer — does NOT remove existing rules.
 * 8-point spacing grid · Inter typography · WCAG AA colour tokens
 */

/* ── SPACING TOKENS (8-pt grid) ─────────────────────────────────────────── */
:root {
  --sp-1:  8px;
  --sp-2:  16px;
  --sp-3:  24px;
  --sp-4:  32px;
  --sp-5:  48px;
  --sp-6:  64px;
  --sp-7:  80px;
  --sp-8:  96px;
  --sp-9:  128px;

  /* Typography scale */
  --fs-h1:   clamp(34px, 4vw, 48px);
  --fs-h2:   clamp(24px, 3vw, 32px);
  --fs-h3:   22px;
  --fs-h4:   17px;
  --fs-body: 15px;
  --fs-sm:   13px;
  --fs-xs:   11px;
  --fs-code: 13px;

  /* Line heights */
  --lh-h1:   1.10;
  --lh-h2:   1.20;
  --lh-h3:   1.30;
  --lh-body: 1.70;
  --lh-sm:   1.60;

  /* Letter spacing */
  --ls-h1: -0.04em;
  --ls-h2: -0.03em;
  --ls-h3: -0.02em;
  --ls-xs: +0.08em;

  /* Card design */
  --card-radius:  14px;
  --card-border:  1px solid #E2E8F0;
  --card-padding: var(--sp-3);
  --card-shadow:  0 1px 2px rgba(15,23,42,.05), 0 4px 16px rgba(15,23,42,.06);
  --card-shadow-h: 0 4px 24px rgba(15,23,42,.10), 0 1px 4px rgba(15,23,42,.06);

  /* Section rhythm */
  --section-gap: var(--sp-7);      /* 80px between major sections */
  --section-px:  var(--sp-4);      /* 32px horizontal padding */
  --section-py:  var(--sp-7);      /* 80px vertical padding */
}

/* ── BASE TYPOGRAPHY ─────────────────────────────────────────────────────── */
/* Only sets properties not already explicitly set by page-level CSS */

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  font-size: var(--fs-body);
  line-height: var(--lh-body);
  color: var(--tx, #0F172A);
  -webkit-font-smoothing: antialiased;
}

/* Section headings — applied only where no more-specific rule exists */
.ds-h1 {
  font-size: var(--fs-h1);
  font-weight: 800;
  line-height: var(--lh-h1);
  letter-spacing: var(--ls-h1);
  color: var(--tx, #0F172A);
}
.ds-h2 {
  font-size: var(--fs-h2);
  font-weight: 700;
  line-height: var(--lh-h2);
  letter-spacing: var(--ls-h2);
  color: var(--tx, #0F172A);
}
.ds-h3 {
  font-size: var(--fs-h3);
  font-weight: 700;
  line-height: var(--lh-h3);
  letter-spacing: var(--ls-h3);
  color: var(--tx, #0F172A);
}
.ds-h4 {
  font-size: var(--fs-h4);
  font-weight: 600;
  line-height: 1.40;
  color: var(--tx, #0F172A);
}
.ds-body  { font-size: var(--fs-body); color: var(--tx2, #334155); line-height: var(--lh-body); }
.ds-sm    { font-size: var(--fs-sm);   color: var(--tx3, #64748B); line-height: var(--lh-sm); }
.ds-xs    { font-size: var(--fs-xs);   color: var(--tx3, #64748B); font-weight: 700; letter-spacing: var(--ls-xs); text-transform: uppercase; }
.ds-mono  { font-family: 'JetBrains Mono', monospace; font-size: var(--fs-code); color: var(--brand, #6366F1); }

/* ── SECTION SPACING ─────────────────────────────────────────────────────── */
/* Adds consistent vertical rhythm between sections */
.ds-section {
  padding: var(--section-py) var(--section-px);
}
.ds-section + .ds-section {
  padding-top: 0;
}
.ds-section-gap {
  margin-top: var(--section-gap);
}

/* Section header pattern: eyebrow + H2 + optional sub */
.ds-section-header {
  margin-bottom: var(--sp-5);     /* 48px below header, before content */
}
.ds-section-header .ds-eyebrow {
  font-size: var(--fs-xs);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--brand, #6366F1);
  margin-bottom: var(--sp-1);    /* 8px */
}
.ds-section-header h2,
.ds-section-header .ds-h2 {
  margin-bottom: var(--sp-2);    /* 16px */
}
.ds-section-header .ds-sub {
  font-size: var(--fs-body);
  color: var(--tx2, #334155);
  line-height: var(--lh-body);
  max-width: 600px;
}

/* ── CARD SYSTEM ─────────────────────────────────────────────────────────── */
.ds-card {
  background: #fff;
  border: var(--card-border);
  border-radius: var(--card-radius);
  padding: var(--card-padding);
  box-shadow: var(--card-shadow);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}
.ds-card:hover {
  box-shadow: var(--card-shadow-h);
  transform: translateY(-2px);
}
.ds-card-lg {
  padding: var(--sp-4);          /* 32px for larger cards */
}

/* ── BUTTON SYSTEM ───────────────────────────────────────────────────────── */
/* Tier 1 — Primary */
.ds-btn-primary {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 11px var(--sp-3);
  background: var(--brand, #6366F1);
  color: #fff;
  border: none;
  border-radius: 10px;
  font-size: 14px; font-weight: 600;
  font-family: 'Inter', sans-serif;
  cursor: pointer; text-decoration: none;
  transition: background 0.15s, transform 0.15s, box-shadow 0.15s;
  box-shadow: 0 0 0 1px rgba(99,102,241,.4), 0 2px 8px rgba(99,102,241,.25);
}
.ds-btn-primary:hover {
  background: var(--brand-l, #818CF8);
  transform: translateY(-1px);
  box-shadow: 0 0 0 1px rgba(99,102,241,.5), 0 8px 24px rgba(99,102,241,.35);
}

/* Tier 2 — Secondary */
.ds-btn-secondary {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 10px var(--sp-3);
  background: #fff;
  color: var(--tx, #0F172A);
  border: 1px solid var(--lb, #E2E8F0);
  border-radius: 10px;
  font-size: 14px; font-weight: 600;
  font-family: 'Inter', sans-serif;
  cursor: pointer; text-decoration: none;
  transition: background 0.15s, border-color 0.15s;
  box-shadow: 0 1px 2px rgba(15,23,42,.05);
}
.ds-btn-secondary:hover {
  background: var(--gray50, #FAFAFB);
  border-color: var(--lb2, #CBD5E1);
}

/* Tier 3 — Ghost */
.ds-btn-ghost {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 9px 18px;
  background: transparent;
  color: var(--brand, #6366F1);
  border: 1px solid transparent;
  border-radius: 10px;
  font-size: 13px; font-weight: 500;
  font-family: 'Inter', sans-serif;
  cursor: pointer; text-decoration: none;
  transition: border-color 0.15s, background 0.15s;
}
.ds-btn-ghost:hover {
  border-color: rgba(99,102,241,.3);
  background: rgba(99,102,241,.06);
}

/* ── BADGE / LABEL ───────────────────────────────────────────────────────── */
.ds-badge {
  display: inline-flex; align-items: center;
  padding: 2px 8px;
  font-size: var(--fs-xs); font-weight: 700;
  letter-spacing: 0.08em; text-transform: uppercase;
  border-radius: 100px;
  border: 1px solid currentColor;
  white-space: nowrap;
}
.ds-badge-brand  { color: var(--brand, #6366F1); background: rgba(99,102,241,.08);  border-color: rgba(99,102,241,.20); }
.ds-badge-green  { color: #059669;                background: rgba(16,185,129,.08);  border-color: rgba(16,185,129,.20); }
.ds-badge-amber  { color: #92400E;                background: rgba(245,158,11,.10);  border-color: rgba(245,158,11,.25); }
.ds-badge-red    { color: #B91C1C;                background: rgba(239,68,68,.08);   border-color: rgba(239,68,68,.20); }

/* ── GRADIENT TEXT (decorative — short phrases only) ─────────────────────── */
.ds-gradient-text {
  background: linear-gradient(135deg, #818CF8 0%, #8B5CF6 50%, #EC4899 100%);
  -webkit-background-clip: text; background-clip: text;
  color: transparent; -webkit-text-fill-color: transparent;
}

/* ── FOCUS VISIBLE (accessibility) ──────────────────────────────────────── */
:focus-visible {
  outline: 2px solid #818CF8;
  outline-offset: 2px;
}

/* ── DIVIDER ─────────────────────────────────────────────────────────────── */
.ds-divider {
  border: none;
  border-top: 1px solid var(--lb, #E2E8F0);
  margin: var(--sp-5) 0;
}

/* ── ARTICLE / BLOG BODY STYLES ──────────────────────────────────────────── */
.article-body h2 {
  font-size: clamp(20px, 2.5vw, 26px);
  font-weight: 700;
  color: var(--tx, #0F172A);
  letter-spacing: -0.02em;
  margin: var(--sp-5) 0 var(--sp-2);   /* 48px top, 16px bottom */
  line-height: 1.25;
}
.article-body h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--tx, #0F172A);
  margin: var(--sp-4) 0 var(--sp-1);   /* 32px top, 8px bottom */
}
.article-body p {
  font-size: 16px;
  color: var(--tx2, #334155);
  line-height: 1.85;
  margin-bottom: var(--sp-2);          /* 16px */
}
.article-body ul,
.article-body ol {
  padding-left: var(--sp-3);
  margin-bottom: var(--sp-2);
  color: var(--tx2, #334155);
  font-size: 16px; line-height: 1.75;
}
.article-body li { margin-bottom: var(--sp-1); }
.article-body strong { color: var(--tx, #0F172A); font-weight: 700; }
.article-body a {
  color: var(--brand, #6366F1);
  border-bottom: 1px solid rgba(99,102,241,.25);
  transition: border-color .15s, background .15s;
}
.article-body a:hover {
  background: rgba(99,102,241,.06);
  border-color: var(--brand);
}

/* ── MOBILE ADJUSTMENTS ──────────────────────────────────────────────────── */
@media (max-width: 768px) {
  :root {
    --section-py: var(--sp-5);   /* 48px on tablet */
    --section-px: var(--sp-2);   /* 16px */
  }
}
@media (max-width: 480px) {
  :root {
    --section-py: var(--sp-4);   /* 32px on phone */
    --card-padding: var(--sp-2); /* 16px */
  }
  .ds-btn-primary,
  .ds-btn-secondary {
    width: 100%; justify-content: center;
  }
}