/* ============================================================
   VWAPEDIA · VWAP A→Z — course design system
   Dark quant-terminal. Green tape, gold VWAP, blood-red risk.
   Self-contained: webfonts progressive-enhance over system stacks.
   ============================================================ */

:root {
  --bg:        #070d0b;
  --bg-2:      #0a1210;
  --panel:     #0e1714;
  --panel-2:   #12201a;
  --line:      #1c2f27;
  --line-2:    #27443a;
  --ink:       #e9f3ed;
  --ink-dim:   #a9bcb2;
  --muted:     #7d938a;
  --green:     #2fd18b;
  --green-dk:  #159c62;
  --green-glo: rgba(47, 209, 139, .14);
  --gold:      #dcaa42;
  --gold-dim:  #a97f2e;
  --red:       #e05c54;
  --red-glo:   rgba(224, 92, 84, .12);
  --blue:      #4aa3e0;
  --violet:    #9d7bde;
  --serif:     "Fraunces", Constantia, "Palatino Linotype", Georgia, serif;
  --sans:      "IBM Plex Sans Arabic", Candara, "Segoe UI", system-ui, sans-serif;
  --mono:      "JetBrains Mono", "Cascadia Code", Consolas, monospace;
  --maxw:      880px;
  --rail:      236px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font-family: var(--sans); font-size: 16.5px; line-height: 1.72;
  -webkit-font-smoothing: antialiased;
}

/* atmospheric backdrop: radial glow + faint grid + grain */
body::before {
  content: ""; position: fixed; inset: 0; z-index: -2; pointer-events: none;
  background:
    radial-gradient(1100px 520px at 18% -8%, rgba(47,209,139,.075), transparent 62%),
    radial-gradient(900px 480px at 108% 12%, rgba(220,170,66,.05), transparent 60%),
    repeating-linear-gradient(0deg, transparent 0 47px, rgba(233,243,237,.017) 47px 48px),
    repeating-linear-gradient(90deg, transparent 0 47px, rgba(233,243,237,.017) 47px 48px);
}
body::after {
  content: ""; position: fixed; inset: 0; z-index: -1; pointer-events: none; opacity: .5;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 .04 0'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ---------- language switching ---------- */
.ar { display: none; }
body[data-lang="ar"] { direction: rtl; }
body[data-lang="ar"] .ar { display: revert; }
body[data-lang="ar"] .en { display: none; }
body[data-lang="ar"] .num, body[data-lang="ar"] code,
body[data-lang="ar"] .mono { direction: ltr; unicode-bidi: embed; }
body[data-lang="ar"] { font-size: 17.5px; }

/* ---------- top bar ---------- */
.topbar {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; gap: 14px;
  padding: 10px 22px; border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  backdrop-filter: blur(9px);
}
.topbar .brand {
  font-family: var(--mono); font-size: 13px; letter-spacing: .14em;
  color: var(--green); text-decoration: none; white-space: nowrap;
}
.topbar .brand b { color: var(--ink); font-weight: 600; }
.topbar .crumb { font-size: 12.5px; color: var(--muted); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.topbar .spacer { flex: 1; }
.lang-toggle {
  font-family: var(--mono); font-size: 12px; cursor: pointer;
  color: var(--ink-dim); background: var(--panel); border: 1px solid var(--line-2);
  border-radius: 999px; padding: 5px 14px; transition: .18s;
}
.lang-toggle:hover { color: var(--green); border-color: var(--green-dk); }

/* scroll progress */
#scrollProgress { position: fixed; top: 0; left: 0; height: 2px; background: linear-gradient(90deg, var(--green), var(--gold)); z-index: 60; width: 0; }

/* ---------- chapter layout ---------- */
.layout { display: grid; grid-template-columns: var(--rail) minmax(0,1fr); gap: 38px; max-width: calc(var(--maxw) + var(--rail) + 38px); margin: 0 auto; padding: 34px 22px 90px; }
@media (max-width: 980px) { .layout { grid-template-columns: 1fr; } .rail { display: none; } }
.rail { position: sticky; top: 64px; align-self: start; font-size: 12.5px; }
.rail h4 { margin: 0 0 8px; font-family: var(--mono); font-size: 10.5px; letter-spacing: .18em; color: var(--muted); text-transform: uppercase; }
.rail a { display: block; color: var(--ink-dim); text-decoration: none; padding: 4px 10px; border-inline-start: 2px solid var(--line); transition: .15s; }
.rail a:hover { color: var(--green); }
.rail a.on { color: var(--green); border-color: var(--green); background: linear-gradient(90deg, var(--green-glo), transparent); }
.rail .rail-sep { height: 14px; }
main { min-width: 0; }

/* ---------- chapter hero ---------- */
.ch-hero { margin: 12px 0 40px; }
.ch-kicker { font-family: var(--mono); font-size: 12px; letter-spacing: .22em; color: var(--gold); text-transform: uppercase; }
.ch-kicker .n { color: var(--green); }
h1 {
  font-family: var(--serif); font-weight: 570; font-size: clamp(30px, 4.6vw, 46px);
  line-height: 1.12; margin: 10px 0 14px; letter-spacing: -.012em;
  background: linear-gradient(115deg, var(--ink) 55%, var(--green) 130%);
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent;
}
.ch-lede { font-size: 18.5px; color: var(--ink-dim); max-width: 62ch; }
.objectives { margin-top: 22px; border: 1px solid var(--line-2); border-radius: 12px; background: linear-gradient(160deg, var(--panel-2), var(--panel)); padding: 16px 20px; }
.objectives h3 { margin: 0 0 8px; font-family: var(--mono); font-size: 11px; letter-spacing: .2em; color: var(--green); text-transform: uppercase; }
.objectives ul { margin: 0; padding-inline-start: 20px; }
.objectives li { margin: 4px 0; color: var(--ink-dim); font-size: 14.5px; }

/* ---------- prose ---------- */
h2 { font-family: var(--serif); font-weight: 560; font-size: 27px; letter-spacing: -.01em; margin: 54px 0 14px; color: var(--ink); }
h2 .sec-n { font-family: var(--mono); font-size: 13px; color: var(--gold); vertical-align: super; margin-inline-end: 8px; letter-spacing: .1em; }
h3 { font-size: 18px; margin: 34px 0 10px; color: var(--green); font-weight: 650; }
p { margin: 13px 0; }
strong { color: var(--ink); } em { color: var(--gold); font-style: normal; }
a { color: var(--green); }
code, .mono { font-family: var(--mono); font-size: .88em; background: var(--panel-2); border: 1px solid var(--line); border-radius: 5px; padding: 1px 6px; color: var(--gold); }
ul, ol { padding-inline-start: 24px; } li { margin: 6px 0; }
hr { border: 0; border-top: 1px dashed var(--line-2); margin: 40px 0; }

/* ---------- callouts ---------- */
.rule, .warn, .mentor, .stat, .drill, .keypoint {
  border-radius: 12px; padding: 15px 19px; margin: 22px 0; border: 1px solid;
  position: relative; overflow: hidden;
}
.rule    { border-color: var(--green-dk); background: linear-gradient(150deg, var(--green-glo), transparent 55%); }
.warn    { border-color: #8a3b36; background: linear-gradient(150deg, var(--red-glo), transparent 55%); }
.mentor  { border-color: var(--line-2); background: var(--panel); font-family: var(--serif); font-size: 17.5px; }
.stat    { border-color: #3d5f83; background: linear-gradient(150deg, rgba(74,163,224,.1), transparent 55%); }
.drill   { border-color: var(--gold-dim); background: linear-gradient(150deg, rgba(220,170,66,.09), transparent 55%); }
.keypoint{ border-color: var(--line-2); background: var(--panel); }
.rule::before, .warn::before, .stat::before, .drill::before, .keypoint::before {
  display: block; font-family: var(--mono); font-size: 10.5px; letter-spacing: .22em;
  text-transform: uppercase; margin-bottom: 6px;
}
.rule::before    { content: "◆ Hard rule";    color: var(--green); }
.warn::before    { content: "⛔ Account killer"; color: var(--red); }
.stat::before    { content: "▦ The numbers";  color: var(--blue); }
.drill::before   { content: "✎ Drill";        color: var(--gold); }
.keypoint::before{ content: "★ Key point";    color: var(--violet); }
body[data-lang="ar"] .rule::before    { content: "◆ قاعدة صارمة"; }
body[data-lang="ar"] .warn::before    { content: "⛔ قاتل الحساب"; }
body[data-lang="ar"] .stat::before    { content: "▦ الأرقام"; }
body[data-lang="ar"] .drill::before   { content: "✎ تمرين"; }
body[data-lang="ar"] .keypoint::before{ content: "★ نقطة أساسية"; }
.mentor .who { display: block; margin-top: 8px; font-family: var(--mono); font-size: 11px; color: var(--muted); letter-spacing: .12em; }

/* ---------- figures (SVG charts) ---------- */
.fig { margin: 30px 0; border: 1px solid var(--line-2); border-radius: 14px; background: linear-gradient(170deg, var(--panel), var(--bg-2)); overflow: hidden; }
.fig svg { display: block; width: 100%; height: auto; direction: ltr; }
.fig .cap { padding: 11px 18px 13px; font-size: 13.5px; color: var(--ink-dim); border-top: 1px solid var(--line); }
.fig .cap b { color: var(--gold); font-family: var(--mono); font-size: 12px; letter-spacing: .08em; }
.fig-controls { display: flex; gap: 8px; flex-wrap: wrap; padding: 10px 14px 2px; direction: ltr; }
.fig-controls button {
  font-family: var(--mono); font-size: 11px; letter-spacing: .06em; cursor: pointer;
  color: var(--ink-dim); background: var(--bg-2); border: 1px solid var(--line-2);
  border-radius: 999px; padding: 4px 12px; transition: .15s;
}
.fig-controls button.on { color: var(--bg); background: var(--green); border-color: var(--green); font-weight: 700; }
.fig-controls button:hover:not(.on) { border-color: var(--green-dk); color: var(--green); }
/* chart vocabulary — use these classes inside SVGs */
.svg-grid   { stroke: #16241e; stroke-width: 1; }
.svg-axis   { fill: #5d7168; font-family: var(--mono); font-size: 10px; }
.candle-up  { fill: #1fbd7e; }  .candle-up-w  { stroke: #1fbd7e; stroke-width: 1.2; }
.candle-dn  { fill: #d8574e; }  .candle-dn-w  { stroke: #d8574e; stroke-width: 1.2; }
.vwap-line  { stroke: var(--gold); stroke-width: 2.4; fill: none; }
.band-line  { stroke: #3f5c50; stroke-width: 1.4; fill: none; stroke-dasharray: 5 4; }
.band-fill  { fill: rgba(47,209,139,.07); }
.ib-line    { stroke: var(--blue); stroke-width: 1.6; fill: none; stroke-dasharray: 8 5; }
.poc-line   { stroke: var(--violet); stroke-width: 2; fill: none; }
.vp-bar     { fill: rgba(125,147,138,.28); }
.vp-bar-poc { fill: rgba(157,123,222,.55); }
.anno       { transition: opacity .25s; }
.anno text  { font-family: var(--sans); font-size: 12.5px; fill: var(--ink); }
.anno .tag  { font-family: var(--mono); font-size: 10.5px; }
.anno-line  { stroke: var(--ink-dim); stroke-width: 1; stroke-dasharray: 2 3; }
.px-long    { fill: var(--green); } .px-short { fill: var(--red); }
.hidden-layer { opacity: 0; pointer-events: none; }

/* ---------- tables ---------- */
table { border-collapse: collapse; width: 100%; margin: 22px 0; font-size: 14px; }
th { font-family: var(--mono); font-size: 11px; letter-spacing: .12em; text-transform: uppercase; color: var(--green); text-align: start; padding: 9px 12px; border-bottom: 2px solid var(--green-dk); }
td { padding: 9px 12px; border-bottom: 1px solid var(--line); color: var(--ink-dim); vertical-align: top; }
tr:hover td { background: rgba(47,209,139,.035); }
td b, td strong { color: var(--ink); }
.tbl-wrap { overflow-x: auto; }

/* ---------- quiz ---------- */
.quiz { margin: 46px 0 10px; border: 1px solid var(--line-2); border-radius: 16px; background: linear-gradient(165deg, var(--panel-2), var(--bg-2)); padding: 22px 24px; }
.quiz > h3 { margin: 0 0 4px; font-family: var(--serif); font-size: 22px; color: var(--ink); }
.quiz .q-sub { font-size: 13px; color: var(--muted); margin-bottom: 18px; font-family: var(--mono); }
.q { margin: 20px 0; padding-top: 16px; border-top: 1px dashed var(--line-2); }
.q .q-text { font-weight: 650; color: var(--ink); margin-bottom: 10px; }
.q .opts { display: grid; gap: 8px; }
.q .opt {
  text-align: start; cursor: pointer; font: inherit; color: var(--ink-dim);
  background: var(--panel); border: 1px solid var(--line-2); border-radius: 10px;
  padding: 10px 14px; transition: .15s;
}
.q .opt:hover { border-color: var(--green-dk); color: var(--ink); }
.q .opt.correct { border-color: var(--green); background: var(--green-glo); color: var(--ink); }
.q .opt.wrong   { border-color: var(--red); background: var(--red-glo); color: var(--ink); }
.q .opt:disabled { cursor: default; }
.q .expl { display: none; margin-top: 10px; font-size: 14px; color: var(--ink-dim); border-inline-start: 3px solid var(--gold); padding: 6px 14px; background: var(--panel); border-radius: 0 8px 8px 0; }
.q.answered .expl { display: block; }
.quiz .score { display: none; margin-top: 20px; font-family: var(--mono); font-size: 14px; padding: 12px 16px; border-radius: 10px; border: 1px solid var(--green-dk); color: var(--green); background: var(--green-glo); }
.quiz.done .score { display: block; }

/* ---------- chapter nav / complete ---------- */
.ch-nav { display: flex; gap: 14px; margin: 40px 0 0; }
.ch-nav a, .mark-done {
  flex: 1; display: block; text-align: center; text-decoration: none; cursor: pointer;
  font-family: var(--mono); font-size: 13px; letter-spacing: .06em;
  color: var(--ink-dim); background: var(--panel); border: 1px solid var(--line-2);
  border-radius: 12px; padding: 15px 10px; transition: .18s;
}
.ch-nav a:hover { color: var(--green); border-color: var(--green-dk); transform: translateY(-2px); }
.ch-nav a small, .ch-nav a .dir { display: block; font-size: 10px; color: var(--muted); letter-spacing: .2em; text-transform: uppercase; margin-bottom: 4px; }
.mark-done.on { color: var(--bg); background: var(--green); border-color: var(--green); font-weight: 700; }

/* ---------- hub (index) ---------- */
.hub-hero { max-width: 1060px; margin: 0 auto; padding: 68px 22px 30px; text-align: center; position: relative; }
.hub-hero .big {
  font-family: var(--serif); font-weight: 580; font-size: clamp(42px, 7vw, 84px);
  line-height: 1.02; letter-spacing: -.02em; margin: 18px 0 6px;
  background: linear-gradient(120deg, var(--ink) 35%, var(--green) 78%, var(--gold) 105%);
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent;
}
.hub-hero .sub { font-size: 19px; color: var(--ink-dim); max-width: 66ch; margin: 12px auto 0; }
.hub-hero .meta { margin-top: 22px; font-family: var(--mono); font-size: 12.5px; color: var(--muted); letter-spacing: .1em; }
.hub-hero .meta b { color: var(--gold); }
.hub-progress { max-width: 620px; margin: 26px auto 0; }
.hub-progress .bar { height: 7px; border-radius: 99px; background: var(--panel-2); border: 1px solid var(--line-2); overflow: hidden; }
.hub-progress .bar i { display: block; height: 100%; width: 0%; border-radius: 99px; background: linear-gradient(90deg, var(--green-dk), var(--green), var(--gold)); transition: width .8s cubic-bezier(.2,.8,.2,1); }
.hub-progress .lbl { margin-top: 8px; font-family: var(--mono); font-size: 12px; color: var(--muted); }

.phase { max-width: 1060px; margin: 40px auto 0; padding: 0 22px; }
.phase > h2 { display: flex; align-items: center; gap: 14px; font-size: 15px; font-family: var(--mono); letter-spacing: .24em; text-transform: uppercase; color: var(--gold); margin: 0 0 18px; }
.phase > h2::after { content: ""; flex: 1; height: 1px; background: linear-gradient(90deg, var(--line-2), transparent); }
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 16px; }
.card {
  position: relative; display: block; text-decoration: none; color: inherit;
  border: 1px solid var(--line-2); border-radius: 16px; padding: 20px 22px 18px;
  background: linear-gradient(165deg, var(--panel-2), var(--bg-2));
  transition: transform .22s, border-color .22s, box-shadow .22s; overflow: hidden;
}
.card::before { content: ""; position: absolute; inset: 0 0 auto; height: 2px; background: linear-gradient(90deg, var(--green), transparent 70%); opacity: 0; transition: .25s; }
.card:hover { transform: translateY(-4px); border-color: var(--green-dk); box-shadow: 0 18px 44px -18px rgba(0,0,0,.65); }
.card:hover::before { opacity: 1; }
.card .ch-no { font-family: var(--mono); font-size: 11px; letter-spacing: .2em; color: var(--gold); }
.card h3 { margin: 8px 0 6px; font-family: var(--serif); font-weight: 580; font-size: 21.5px; color: var(--ink); line-height: 1.2; }
.card p { margin: 0; font-size: 13.8px; color: var(--muted); line-height: 1.55; }
.card .foot { display: flex; align-items: center; justify-content: space-between; margin-top: 14px; font-family: var(--mono); font-size: 11px; color: var(--muted); }
.card .done-chip { color: var(--green); }
.card .ring { width: 30px; height: 30px; }
.card .ring circle { fill: none; stroke-width: 3; }
.card .ring .track { stroke: var(--line-2); }
.card .ring .val { stroke: var(--green); stroke-linecap: round; transform: rotate(-90deg); transform-origin: center; transition: stroke-dashoffset .7s; }

/* ---------- CTA row + bottom band ---------- */
.cta-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-top: 26px; }
.btn-cta {
  display: inline-block; text-decoration: none;
  font-family: var(--mono); font-size: 13px; letter-spacing: .08em;
  color: var(--ink-dim); background: var(--panel); border: 1px solid var(--line-2);
  border-radius: 999px; padding: 13px 26px; transition: .18s;
}
body[data-lang="ar"] .btn-cta { font-family: var(--sans); font-weight: 600; letter-spacing: 0; }
.btn-cta:hover { color: var(--green); border-color: var(--green-dk); transform: translateY(-2px); }
.btn-cta.primary {
  color: var(--bg); font-weight: 700;
  background: linear-gradient(120deg, var(--green), var(--green-dk));
  border-color: var(--green);
  box-shadow: 0 12px 34px -12px rgba(47,209,139,.55);
}
.btn-cta.primary:hover { color: var(--bg); filter: brightness(1.07); }
.cta-band { max-width: 1060px; margin: 64px auto 0; padding: 0 22px; }
.cta-band .inner {
  position: relative; overflow: hidden; text-align: center;
  border: 1px solid var(--line-2); border-radius: 18px; padding: 34px 26px 30px;
  background: linear-gradient(165deg, var(--panel-2), var(--bg-2));
}
.cta-band .inner::before { content: ""; position: absolute; inset: 0 0 auto; height: 2px; background: linear-gradient(90deg, var(--green), var(--gold), transparent); }
.cta-band h2 { margin: 0 0 8px; font-family: var(--serif); font-weight: 570; font-size: clamp(22px, 3vw, 28px); color: var(--ink); }
.cta-band p { margin: 0 auto; max-width: 62ch; font-size: 14.5px; color: var(--ink-dim); }
.cta-band .cta-row { margin-top: 22px; }

.hub-foot { max-width: 1060px; margin: 60px auto 0; padding: 26px 22px 60px; border-top: 1px solid var(--line); font-size: 12.5px; color: var(--muted); text-align: center; }

/* ---------- reveal animations ---------- */
@media (prefers-reduced-motion: no-preference) {
  .rv { opacity: 0; transform: translateY(16px); transition: opacity .6s ease, transform .6s cubic-bezier(.2,.8,.2,1); }
  .rv.in { opacity: 1; transform: none; }
  .hub-hero .big, .hub-hero .sub, .hub-hero .meta, .hub-hero .cta-row, .hub-progress { animation: rise .8s cubic-bezier(.2,.8,.2,1) backwards; }
  .hub-hero .sub { animation-delay: .12s; } .hub-hero .meta { animation-delay: .22s; } .hub-hero .cta-row { animation-delay: .3s; } .hub-progress { animation-delay: .38s; }
  @keyframes rise { from { opacity: 0; transform: translateY(22px); } }
}

/* ---------- print ---------- */
@media print {
  body { background: #fff; color: #14201a; }
  body::before, body::after, .topbar, .rail, .fig-controls, .ch-nav, .lang-toggle, #scrollProgress, .cta-row, .cta-band { display: none !important; }
  .layout { display: block; padding: 0; }
  h1 { -webkit-text-fill-color: initial; color: #0d3f2c; }
  .fig, .rule, .warn, .stat, .drill, .keypoint, .mentor, .quiz { break-inside: avoid; border-color: #c8d6cf; background: #fff; }
}

/* ---------- VWAPEDIA logo branding ---------- */
.topbar .brand { display: inline-flex; align-items: center; gap: 9px; }
.topbar .logo-mark { height: 26px; width: 26px; border-radius: 50%; box-shadow: 0 0 0 1px var(--line-2), 0 0 14px rgba(220,170,66,.25); }
.hub-logo { width: 132px; height: 132px; border-radius: 30px; margin-bottom: 10px;
  box-shadow: 0 14px 48px -12px rgba(220,170,66,.4), 0 0 0 1px var(--line-2);
  animation: rise .8s cubic-bezier(.2,.8,.2,1) backwards; }
@media print { .hub-logo { box-shadow: none; } }