/* ── domain-shared.css ───────────────────────────────────────────────── */
:root {
  --ink:       #0D0E14;
  --ink-2:     #2A2D3A;
  --ink-3:     #5C6178;
  --paper:     #F8F7F3;
  --paper-2:   #EFEDE6;
  --paper-3:   #E5E2D8;
  --amber:     #C47900;
  --amber-lt:  #F5A623;
  --rule:      #D4D0C4;
  --font-display: 'Syne', sans-serif;
  --font-body:    'DM Sans', sans-serif;
  --font-mono:    'DM Mono', monospace;
  --max-w: 1200px;
  --col-w:  740px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body { background: var(--paper); color: var(--ink); font-family: var(--font-body); line-height: 1.7; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }

/* Nav */
nav { position: fixed; top: 0; left: 0; right: 0; z-index: 100; background: rgba(248,247,243,0.92); backdrop-filter: blur(12px); border-bottom: 1px solid var(--rule); padding: 0 2rem; height: 60px; display: flex; align-items: center; justify-content: space-between; }
.nav-logo { font-family: var(--font-display); font-weight: 800; font-size: 0.9rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink); }
.nav-logo span { color: var(--amber); }
.nav-links { display: flex; gap: 2rem; list-style: none; }
.nav-links a { font-size: 0.8rem; font-weight: 500; letter-spacing: 0.06em; text-transform: uppercase; color: var(--ink-3); transition: color 0.2s; }
.nav-links a:hover, .nav-links a.active { color: var(--amber); }
.nav-cta { background: var(--ink); color: var(--paper) !important; padding: 0.45rem 1.1rem; border-radius: 2px; }
.nav-cta:hover { background: var(--amber) !important; }

/* Domain hero */
.domain-hero { padding-top: 60px; background: var(--ink); min-height: 380px; position: relative; overflow: hidden; display: flex; flex-direction: column; justify-content: flex-end; }
.domain-hero-grid { position: absolute; inset: 0; background-image: linear-gradient(rgba(196,121,0,0.06) 1px, transparent 1px), linear-gradient(90deg, rgba(196,121,0,0.06) 1px, transparent 1px); background-size: 60px 60px; }
.domain-hero-inner { max-width: var(--max-w); margin: 0 auto; padding: 4rem 6rem 3.5rem; position: relative; z-index: 2; width: 100%; }
.domain-breadcrumb { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 2rem; }
.domain-breadcrumb a { font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.12em; text-transform: uppercase; color: rgba(255,255,255,0.3); transition: color 0.2s; }
.domain-breadcrumb a:hover { color: var(--amber); }
.domain-breadcrumb-sep { color: rgba(255,255,255,0.15); font-size: 0.7rem; }
.domain-num-label { font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--amber); margin-bottom: 0.75rem; }
.domain-hero-title { font-family: var(--font-display); font-size: clamp(2.2rem, 4vw, 3.8rem); font-weight: 800; color: var(--paper); line-height: 1.05; letter-spacing: -0.02em; margin-bottom: 1.25rem; }
.domain-hero-sub { font-size: 1rem; font-weight: 300; color: rgba(255,255,255,0.5); max-width: 600px; line-height: 1.8; margin-bottom: 2rem; }
.domain-hero-meta { display: flex; gap: 2.5rem; align-items: center; }
.domain-meta-item { display: flex; flex-direction: column; gap: 0.2rem; }
.domain-meta-num { font-family: var(--font-display); font-size: 1.6rem; font-weight: 800; color: var(--amber); line-height: 1; }
.domain-meta-label { font-family: var(--font-mono); font-size: 0.62rem; letter-spacing: 0.1em; text-transform: uppercase; color: rgba(255,255,255,0.25); }
.domain-meta-div { width: 1px; height: 36px; background: rgba(255,255,255,0.08); }

/* Layout */
.domain-layout { max-width: var(--max-w); margin: 0 auto; display: grid; grid-template-columns: 260px 1fr; gap: 0; align-items: start; }
.domain-sidebar { position: sticky; top: 60px; height: calc(100vh - 60px); overflow-y: auto; padding: 3rem 2rem; border-right: 1px solid var(--rule); }
.sidebar-label { font-family: var(--font-mono); font-size: 0.62rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--ink-3); margin-bottom: 1.2rem; }
.sidebar-nav { list-style: none; display: flex; flex-direction: column; gap: 0; }
.sidebar-nav li a { display: block; padding: 0.6rem 0.75rem; font-size: 0.82rem; font-weight: 400; color: var(--ink-3); border-left: 2px solid transparent; transition: all 0.2s; line-height: 1.4; }
.sidebar-nav li a:hover { color: var(--amber); border-left-color: var(--amber); background: var(--paper-2); }
.sidebar-nav li a.active { color: var(--amber); border-left-color: var(--amber); font-weight: 600; }
.sidebar-progress { margin-top: 2rem; padding-top: 2rem; border-top: 1px solid var(--rule); }
.sidebar-progress-label { font-family: var(--font-mono); font-size: 0.62rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-3); margin-bottom: 0.75rem; }
.progress-domains { display: flex; flex-direction: column; gap: 0.4rem; }
.progress-domain { font-size: 0.75rem; color: var(--ink-3); padding: 0.3rem 0.5rem; border-radius: 2px; transition: background 0.2s; }
.progress-domain.current { color: var(--amber); font-weight: 600; background: rgba(196,121,0,0.08); }
.progress-domain a { color: inherit; }
.progress-domain a:hover { color: var(--amber); }

/* Content */
.domain-content { padding: 4rem 5rem; }
.content-section { margin-bottom: 5rem; scroll-margin-top: 80px; }

/* Typography */
.eyebrow { font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--amber); margin-bottom: 0.6rem; }
h2.content-h2 { font-family: var(--font-display); font-size: 2rem; font-weight: 800; color: var(--ink); line-height: 1.15; letter-spacing: -0.01em; margin-bottom: 1.25rem; }
h3.content-h3 { font-family: var(--font-display); font-size: 1.2rem; font-weight: 700; color: var(--ink-2); margin-top: 2rem; margin-bottom: 0.75rem; }
p.body-text { font-size: 0.95rem; font-weight: 300; color: var(--ink-3); line-height: 1.85; margin-bottom: 1.1rem; }
p.body-text strong { color: var(--ink); font-weight: 600; }

/* Task statement block */
.task-block { border-top: 3px solid var(--amber); padding-top: 2rem; margin-bottom: 3.5rem; }
.task-code { font-family: var(--font-mono); font-size: 0.7rem; color: var(--amber); letter-spacing: 0.1em; margin-bottom: 0.5rem; }
.task-title { font-family: var(--font-display); font-size: 1.35rem; font-weight: 800; color: var(--ink); margin-bottom: 1rem; }

/* Callout box */
.callout { background: var(--paper-2); border: 1px solid var(--rule); border-left: 3px solid var(--amber); padding: 1.5rem 1.75rem; margin: 1.5rem 0; }
.callout-label { font-family: var(--font-mono); font-size: 0.65rem; letter-spacing: 0.15em; text-transform: uppercase; color: var(--amber); margin-bottom: 0.75rem; }
.callout p { font-size: 0.875rem; font-weight: 400; color: var(--ink-2); line-height: 1.75; margin-bottom: 0.5rem; }
.callout p:last-child { margin-bottom: 0; }
.callout.danger { border-left-color: #c0392b; }
.callout.danger .callout-label { color: #c0392b; }
.callout.dark { background: var(--ink); border: 1px solid rgba(255,255,255,0.08); border-left: 3px solid var(--amber); }
.callout.dark p { color: rgba(255,255,255,0.7); }
.callout.dark .callout-label { color: var(--amber); }

/* Code block */
.code-block { background: var(--ink); border: 1px solid rgba(255,255,255,0.05); padding: 1.25rem 1.5rem; font-family: var(--font-mono); font-size: 0.78rem; color: var(--amber-lt); line-height: 1.75; margin: 1.25rem 0; overflow-x: auto; border-radius: 2px; }
.code-block .comment { color: rgba(255,255,255,0.25); }
.code-block .good { color: #7ec8a4; }
.code-block .bad { color: #e07070; }

/* List */
.content-list { list-style: none; padding: 0; margin: 1rem 0 1.5rem; display: flex; flex-direction: column; gap: 0.5rem; }
.content-list li { font-size: 0.9rem; font-weight: 300; color: var(--ink-3); line-height: 1.7; padding-left: 1.5rem; position: relative; }
.content-list li::before { content: '—'; position: absolute; left: 0; color: var(--amber); font-weight: 700; }
.content-list li strong { color: var(--ink); font-weight: 600; }

/* Table */
.content-table { width: 100%; border-collapse: collapse; margin: 1.5rem 0; font-size: 0.85rem; }
.content-table th { background: var(--ink-2); color: var(--paper); font-family: var(--font-display); font-weight: 700; font-size: 0.78rem; letter-spacing: 0.06em; text-transform: uppercase; padding: 0.75rem 1rem; text-align: left; }
.content-table td { padding: 0.75rem 1rem; border-bottom: 1px solid var(--rule); color: var(--ink-3); vertical-align: top; line-height: 1.65; }
.content-table td strong { color: var(--ink); font-weight: 600; }
.content-table tr:nth-child(even) td { background: var(--paper-2); }

/* Practice scenario */
.practice-box { background: var(--ink); padding: 2rem 2.25rem; margin: 2rem 0; }
.practice-label { font-family: var(--font-mono); font-size: 0.65rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--amber); margin-bottom: 1rem; }
.practice-title { font-family: var(--font-display); font-size: 1rem; font-weight: 700; color: var(--paper); margin-bottom: 0.75rem; }
.practice-body { font-size: 0.875rem; font-weight: 300; color: rgba(255,255,255,0.55); line-height: 1.8; margin-bottom: 1rem; }
.practice-answer { background: rgba(196,121,0,0.1); border-left: 2px solid var(--amber); padding: 1rem 1.25rem; font-size: 0.85rem; color: rgba(255,255,255,0.7); line-height: 1.75; }
.practice-answer strong { color: var(--amber); }

/* Build exercise */
.build-box { background: var(--amber); padding: 2.5rem; margin-top: 3rem; }
.build-label { font-family: var(--font-mono); font-size: 0.65rem; letter-spacing: 0.18em; text-transform: uppercase; color: rgba(13,14,20,0.55); margin-bottom: 0.75rem; }
.build-title { font-family: var(--font-display); font-size: 1.25rem; font-weight: 800; color: var(--ink); margin-bottom: 1rem; }
.build-list { list-style: none; padding: 0; display: flex; flex-direction: column; gap: 0.5rem; }
.build-list li { font-size: 0.9rem; color: rgba(13,14,20,0.75); padding-left: 1.5rem; position: relative; }
.build-list li::before { content: '✓'; position: absolute; left: 0; font-weight: 700; color: var(--ink); }

/* Domain nav footer */
.domain-nav-footer { border-top: 1px solid var(--rule); padding: 3rem 5rem; display: flex; justify-content: space-between; align-items: center; background: var(--paper-2); }
.domain-nav-btn { display: flex; flex-direction: column; gap: 0.3rem; }
.domain-nav-btn .nav-dir { font-family: var(--font-mono); font-size: 0.65rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-3); }
.domain-nav-btn .nav-title { font-family: var(--font-display); font-size: 1rem; font-weight: 700; color: var(--ink); transition: color 0.2s; }
.domain-nav-btn:hover .nav-title { color: var(--amber); }
.domain-nav-btn.next { text-align: right; }

/* Footer */
footer { background: var(--ink-2); padding: 3rem 6rem; }
.footer-inner { max-width: var(--max-w); margin: 0 auto; display: flex; justify-content: space-between; align-items: center; }
.footer-logo { font-family: var(--font-display); font-weight: 800; font-size: 0.9rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--paper); }
.footer-logo span { color: var(--amber); }
.footer-links-row { display: flex; gap: 2rem; list-style: none; }
.footer-links-row a { font-size: 0.78rem; color: rgba(255,255,255,0.3); transition: color 0.2s; }
.footer-links-row a:hover { color: var(--amber); }

/* Responsive */
@media (max-width: 900px) {
  .domain-layout { grid-template-columns: 1fr; }
  .domain-sidebar { display: none; }
  .domain-content { padding: 2.5rem 1.5rem; }
  .domain-hero-inner { padding: 3rem 1.5rem 2.5rem; }
  .domain-nav-footer { padding: 2rem 1.5rem; }
  footer { padding: 2rem 1.5rem; }
  .footer-inner { flex-direction: column; gap: 1.5rem; text-align: center; }
  .footer-links-row { flex-wrap: wrap; justify-content: center; }
}