/* =============================================================
   C-Phase-1 · Centralized Stylesheet
   All pages link to this file.
   To change the look of everything — edit here only.
============================================================= */

:root {
  --bg:     #0d0f14;
  --panel:  #131720;
  --border: #1e2535;
  --accent: #00e5ff;
  --green:  #00ff88;
  --orange: #ff6b35;
  --purple: #bd93f9;
  --dim:    #4a5568;
  --text:   #cdd6f4;
  --muted:  #6b7a99;
}

/* ── RESET ── */
* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'JetBrains Mono', monospace;
  min-height: 100vh;
  overflow-x: hidden;
}

/* scanline overlay */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background: repeating-linear-gradient(
    0deg,
    transparent, transparent 2px,
    rgba(0,0,0,0.03) 2px, rgba(0,0,0,0.03) 4px
  );
  pointer-events: none;
  z-index: 100;
}

/* ── HERO ── */
.hero {
  padding: 40px 40px 30px;
  border-bottom: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}
.hero::after {
  content: '';
  position: absolute;
  top: -80px; right: -80px;
  width: 400px; height: 400px;
  background: radial-gradient(circle, rgba(0,229,255,0.05) 0%, transparent 70%);
  pointer-events: none;
}
.hero-lg { padding: 60px 40px 40px; }

/* ── BREADCRUMB ── */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
  font-size: 11px;
  color: var(--dim);
}
.breadcrumb a {
  color: var(--dim);
  text-decoration: none;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  transition: color 0.15s;
}
.breadcrumb a:hover { color: var(--accent); }
.breadcrumb .sep { color: var(--border); }
.breadcrumb .current { color: var(--muted); }

/* ── HEADINGS ── */
h1 {
  font-family: 'Bebas Neue', sans-serif;
  font-size: clamp(36px, 6vw, 96px);
  letter-spacing: 0.04em;
  line-height: 0.9;
  color: #fff;
}
h1 span { color: var(--accent); }
h1.lg   { font-size: clamp(52px, 8vw, 96px); }

.subtitle {
  margin-top: 10px;
  color: var(--muted);
  font-size: 12px;
  letter-spacing: 0.05em;
}

/* ── TAGS ── */
.hero-tags { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 20px; }
.tag {
  display: inline-block;
  background: rgba(0,229,255,0.1);
  border: 1px solid rgba(0,229,255,0.3);
  color: var(--accent);
  font-size: 11px;
  letter-spacing: 0.15em;
  padding: 4px 12px;
  text-transform: uppercase;
}
.tag.orange { background: rgba(255,107,53,0.1); border-color: rgba(255,107,53,0.3); color: var(--orange); }
.tag.green  { background: rgba(0,255,136,0.1);  border-color: rgba(0,255,136,0.3);  color: var(--green); }

/* ── ENV BAR ── */
.env-bar {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}
.env-item { font-size: 11px; color: var(--muted); }
.env-item span { color: var(--accent); }

/* ── TABS ── */
.tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
  padding: 0 40px;
  overflow-x: auto;
  scrollbar-width: none;
}
.tabs::-webkit-scrollbar { display: none; }

.tab {
  padding: 14px 22px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border: none;
  background: none;
  color: var(--dim);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  transition: all 0.2s;
  white-space: nowrap;
}
.tab:hover  { color: var(--text); }
.tab.active { color: var(--accent); border-bottom-color: var(--accent); }

/* ── CONTENT ── */
.content { padding: 40px; max-width: 960px; }

.section { display: none; }
.section.active { display: block; animation: fadeIn 0.25s ease; }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── SECTION HEADER ── */
.section-title {
  font-family: 'Bebas Neue', sans-serif;
  font-size: 36px;
  color: #fff;
  letter-spacing: 0.06em;
  margin-bottom: 6px;
}
.section-desc {
  font-size: 12px;
  color: var(--muted);
  margin-bottom: 14px;
  letter-spacing: 0.04em;
}
.concepts { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 32px; }
.concept {
  font-size: 10px;
  padding: 3px 10px;
  background: rgba(189,147,249,0.08);
  border: 1px solid rgba(189,147,249,0.2);
  color: var(--purple);
  letter-spacing: 0.1em;
}

/* ── DISCOVERY BLOCKS ── */
.discovery {
  margin-bottom: 28px;
  border-left: 2px solid var(--border);
  padding-left: 24px;
}
.discovery.ok   { border-left-color: var(--green); }
.discovery.warn { border-left-color: var(--orange); }
.discovery.info { border-left-color: var(--accent); }

.disc-label {
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 6px;
}
.discovery.ok   .disc-label { color: var(--green); }
.discovery.warn .disc-label { color: var(--orange); }
.discovery.info .disc-label { color: var(--accent); }
.discovery h3 { font-size: 13px; font-weight: 600; color: #fff; margin-bottom: 8px; }
.discovery p  { font-size: 12px; color: var(--muted); line-height: 1.75; }

/* ── TERMINAL ── */
.term {
  background: #080a0f;
  border: 1px solid var(--border);
  border-radius: 4px;
  overflow: hidden;
  margin: 10px 0;
}
.term-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 14px;
  background: #0e1018;
  border-bottom: 1px solid var(--border);
}
.term-dots { display: flex; gap: 6px; }
.dot { width: 10px; height: 10px; border-radius: 50%; }
.dot.r { background: #ff5f57; }
.dot.y { background: #febc2e; }
.dot.g { background: #28c840; }
.term-label { font-size: 11px; color: var(--dim); letter-spacing: 0.1em; }

.copy-btn {
  background: none;
  border: 1px solid var(--dim);
  color: var(--dim);
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  padding: 3px 10px;
  cursor: pointer;
  letter-spacing: 0.05em;
  transition: all 0.2s;
}
.copy-btn:hover  { border-color: var(--accent); color: var(--accent); }
.copy-btn.copied { border-color: var(--green);  color: var(--green); }

.term-body { padding: 16px; overflow-x: auto; }
.term-body pre {
  font-size: 13px;
  line-height: 1.8;
  color: var(--text);
  white-space: pre;
}

/* syntax highlight spans */
.p   { color: var(--green); }
.cmd { color: #fff; font-weight: 600; }
.arg { color: var(--accent); }
.cmt { color: var(--dim); font-style: italic; }
.out { color: var(--muted); }
.key { color: var(--orange); }
.val { color: var(--purple); }
.str { color: #f1fa8c; }
.err { color: var(--orange); }

/* ── NOTES ── */
.note {
  background: rgba(0,229,255,0.05);
  border-left: 3px solid var(--accent);
  padding: 12px 16px;
  font-size: 12px;
  color: var(--muted);
  margin: 12px 0 24px;
  line-height: 1.6;
}
.note strong { color: var(--accent); }

.warn-note {
  background: rgba(255,107,53,0.05);
  border-left: 3px solid var(--orange);
  padding: 12px 16px;
  font-size: 12px;
  color: var(--muted);
  margin: 12px 0 24px;
  line-height: 1.6;
}
.warn-note strong { color: var(--orange); }

/* ── VERSION TABLE ── */
.vtable { width: 100%; border-collapse: collapse; margin: 16px 0 28px; }
.vtable th {
  font-size: 10px;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--dim);
  padding: 8px 12px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.vtable td {
  font-size: 12px;
  padding: 10px 12px;
  border-bottom: 1px solid rgba(30,37,53,0.6);
  vertical-align: top;
  color: var(--muted);
}
.vtable tr:hover td { background: rgba(255,255,255,0.02); }
.vname { color: var(--accent) !important; font-weight: 600; }
.vok   { color: var(--green)  !important; }
.vfail { color: var(--orange) !important; }

/* ── INDEX PAGE SPECIFICS ── */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 12px;
  margin-bottom: 32px;
}
.stat {
  background: var(--panel);
  border: 1px solid var(--border);
  padding: 16px;
}
.stat-num {
  font-family: 'Bebas Neue', sans-serif;
  font-size: 36px;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 4px;
}
.stat-label { font-size: 10px; color: var(--muted); letter-spacing: 0.12em; text-transform: uppercase; }

.section-label {
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--dim);
  margin-bottom: 16px;
  margin-top: 40px;
}
.section-label:first-child { margin-top: 0; }

.topic {
  border: 1px solid var(--border);
  margin-bottom: 24px;
  background: var(--panel);
}
.topic-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 20px;
  border-bottom: 1px solid var(--border);
}
.topic-title {
  font-family: 'Bebas Neue', sans-serif;
  font-size: 22px;
  letter-spacing: 0.08em;
  color: #fff;
}
.topic-desc { font-size: 11px; color: var(--muted); margin-top: 3px; }
.topic-badge {
  font-size: 10px;
  padding: 3px 10px;
  letter-spacing: 0.1em;
  border: 1px solid;
  white-space: nowrap;
}
.topic-badge.active  { color: var(--green); border-color: rgba(0,255,136,0.3); background: rgba(0,255,136,0.08); }
.topic-badge.planned { color: var(--dim);   border-color: var(--border);        background: transparent; }

.chapters {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 1px;
  background: var(--border);
}
.chapter {
  background: var(--bg);
  padding: 16px 20px;
  text-decoration: none;
  display: block;
  transition: background 0.15s;
  position: relative;
}
.chapter:hover { background: #0f1218; }
.chapter:hover .chapter-arrow { color: var(--accent); }
.chapter-num  { font-size: 10px; color: var(--dim); letter-spacing: 0.15em; margin-bottom: 6px; }
.chapter-name { font-size: 13px; color: #fff; font-weight: 600; margin-bottom: 4px; }
.chapter-exercises { font-size: 11px; color: var(--muted); }
.chapter-arrow { position: absolute; top: 16px; right: 16px; color: var(--dim); font-size: 14px; transition: color 0.15s; }
.chapter-status {
  display: inline-block;
  margin-top: 8px;
  font-size: 10px;
  padding: 2px 8px;
  letter-spacing: 0.08em;
}
.chapter-status.done { color: var(--green);  background: rgba(0,255,136,0.08); border: 1px solid rgba(0,255,136,0.2); }
.chapter-status.wip  { color: var(--orange); background: rgba(255,107,53,0.08); border: 1px solid rgba(255,107,53,0.2); }
.chapter-status.todo { color: var(--dim);    background: transparent; border: 1px solid var(--border); }

/* ── UTILITY ── */
code {
  background: rgba(0,229,255,0.08);
  color: var(--accent);
  padding: 1px 6px;
  font-size: 0.9em;
  font-family: 'JetBrains Mono', monospace;
}
hr { border: none; border-top: 1px solid var(--border); margin: 32px 0; }

/* ── RESPONSIVE ── */
@media (max-width: 768px) {
  .hero, .hero-lg, .content { padding: 24px 20px; }
  .tabs { padding: 0 20px; }
  h1, h1.lg { font-size: 48px; }
  .env-bar  { gap: 12px; }
  .stats    { grid-template-columns: repeat(2, 1fr); }
  .chapters { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  h1, h1.lg { font-size: 38px; }
  .stats { grid-template-columns: 1fr 1fr; }
  .tab  { padding: 12px 14px; font-size: 11px; }
}

/* ── DEEP EXPLANATION BLOCKS ── */
.explain {
  background: var(--panel);
  border: 1px solid var(--border);
  padding: 20px 24px;
  margin: 16px 0 24px;
  font-size: 12px;
  color: var(--muted);
  line-height: 1.85;
}
.explain h4 {
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 10px;
}
.explain p         { margin-bottom: 10px; }
.explain p:last-child { margin-bottom: 0; }
.explain strong    { color: var(--text); }
.explain em        { color: var(--purple); font-style: normal; }

/* ── MEMORY / STACK DIAGRAMS ── */
.memory-diagram {
  background: #080a0f;
  border: 1px solid var(--border);
  padding: 16px;
  margin: 12px 0;
  overflow-x: auto;
}
.memory-diagram pre {
  font-size: 12px;
  line-height: 2;
  white-space: pre;
  color: var(--muted);
}
.mval     { color: var(--green); }
.mlabel   { color: var(--accent); }
.munknown { color: var(--orange); }

/* ── SECTION DIVIDER ── */
hr.sd {
  border: none;
  border-top: 1px solid var(--border);
  margin: 36px 0;
}