/* ============================================================
   AWDL/AirDrop Course — Cyberpunk Hacker Design System
   ============================================================ */

:root {
  /* surfaces */
  --bg-void: #030506;
  --bg-deep: #060a0d;
  --bg-panel: #0a1014;
  --bg-elevated: #0f161b;
  --bg-code: #070b0e;

  /* borders / lines */
  --line: #18242b;
  --line-strong: #243640;
  --line-faint: #0e171c;

  /* text */
  --fg: #d5e0e6;
  --fg-muted: #8a9aa3;
  --fg-dim: #57676f;
  --fg-faint: #3a464c;

  /* accents */
  --acid: #00ff88;
  --acid-dim: #008a4a;
  --cyan: #00d9ff;
  --cyan-dim: #007a90;
  --amber: #ffb627;
  --amber-dim: #8a5e10;
  --red: #ff3b5c;
  --red-dim: #8a1a2e;
  --magenta: #ff39c6;

  /* type */
  --mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, monospace;
  --ar: "IBM Plex Sans Arabic", "Tajawal", "Noto Sans Arabic", system-ui, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg-void);
  color: var(--fg);
  font-family: var(--ar);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* ascii grid + scanline atmosphere */
body {
  background-image:
    repeating-linear-gradient(
      0deg,
      rgba(0, 255, 136, 0.012) 0px,
      rgba(0, 255, 136, 0.012) 1px,
      transparent 1px,
      transparent 3px
    ),
    radial-gradient(ellipse at top, rgba(0, 217, 255, 0.04) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 80%, rgba(0, 255, 136, 0.03) 0%, transparent 50%);
  background-attachment: fixed;
  min-height: 100vh;
}

::selection { background: var(--acid); color: var(--bg-void); }

a { color: var(--acid); text-decoration: none; border-bottom: 1px dashed var(--acid-dim); }
a:hover { color: var(--cyan); border-color: var(--cyan); }

/* ============================================================
   LAYOUT
   ============================================================ */

.shell {
  display: grid;
  grid-template-columns: 320px 1fr;
  min-height: 100vh;
}

/* topbar */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 10px 28px;
  background: var(--bg-void);
  border-bottom: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--fg-dim);
}

.topbar .brand {
  color: var(--acid);
  font-weight: 700;
  display: flex; align-items: center; gap: 8px;
}
.topbar .brand::before {
  content: "▮";
  color: var(--acid);
  animation: blink 1.4s steps(2, end) infinite;
}
.topbar .meta { display: flex; gap: 18px; flex-wrap: wrap; }
.topbar .meta b { color: var(--cyan); font-weight: 500; }
.topbar .spacer { flex: 1; }
.topbar .status {
  color: var(--acid);
  display: flex; align-items: center; gap: 6px;
}
.topbar .status::before {
  content: "";
  width: 8px; height: 8px;
  background: var(--acid);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--acid);
  animation: pulse 1.8s ease-in-out infinite;
}

@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0; } }
@keyframes pulse { 0%, 100% { opacity: 1; transform: scale(1); } 50% { opacity: 0.4; transform: scale(0.7); } }

/* sidebar nav */
.sidebar {
  position: sticky;
  top: 39px;
  height: calc(100vh - 39px);
  overflow-y: auto;
  background: var(--bg-deep);
  border-left: 1px solid var(--line);
  padding: 28px 22px 60px;
  font-family: var(--mono);
  font-size: 13px;
}

.sidebar .sb-title {
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--fg-dim);
  margin: 20px 0 8px;
  display: flex; align-items: center; gap: 8px;
}
.sidebar .sb-title::before {
  content: "";
  display: inline-block;
  width: 6px; height: 6px;
  background: var(--acid);
  transform: rotate(45deg);
}
.sidebar .sb-title:first-child { margin-top: 0; }

.sidebar a {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 7px 10px;
  border: none;
  border-radius: 0;
  color: var(--fg-muted);
  border-right: 2px solid transparent;
  font-size: 13px;
  line-height: 1.5;
  margin-bottom: 1px;
  transition: all 0.12s;
}
.sidebar a:hover {
  background: var(--bg-elevated);
  color: var(--fg);
  border-right-color: var(--acid-dim);
}
.sidebar a.active {
  background: var(--bg-elevated);
  color: var(--acid);
  border-right-color: var(--acid);
}
.sidebar a .num {
  color: var(--fg-dim);
  font-size: 11px;
  flex-shrink: 0;
  min-width: 22px;
}
.sidebar a.active .num { color: var(--acid); }

/* main */
.main {
  padding: 56px 64px 120px;
  max-width: 1100px;
  width: 100%;
}

/* ============================================================
   TYPE
   ============================================================ */

h1, h2, h3, h4 {
  font-family: var(--ar);
  font-weight: 700;
  color: var(--fg);
  line-height: 1.3;
  text-wrap: balance;
}

h1 {
  font-size: clamp(34px, 4vw, 52px);
  margin: 0 0 12px;
  letter-spacing: -0.01em;
}
h1 .accent { color: var(--acid); }

h2 {
  font-size: 30px;
  margin: 64px 0 18px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
  position: relative;
}
h2::before {
  content: attr(data-num);
  display: inline-block;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--acid);
  margin-left: 14px;
  padding: 2px 8px;
  background: rgba(0, 255, 136, 0.06);
  border: 1px solid var(--acid-dim);
  letter-spacing: 0.05em;
  vertical-align: middle;
}

h3 {
  font-size: 22px;
  margin: 40px 0 12px;
  color: var(--cyan);
}
h3::before {
  content: "// ";
  font-family: var(--mono);
  color: var(--fg-dim);
  font-weight: 400;
}

h4 {
  font-size: 17px;
  margin: 28px 0 10px;
  color: var(--amber);
  font-family: var(--mono);
  font-weight: 500;
  letter-spacing: 0.02em;
}

p { margin: 0 0 16px; text-wrap: pretty; }

strong, b { color: var(--fg); font-weight: 700; }
em { color: var(--cyan); font-style: normal; font-weight: 500; }

ul, ol { padding-right: 22px; margin: 0 0 18px; }
li { margin-bottom: 8px; }
li::marker { color: var(--acid); }

/* English/code inline */
code, .en {
  font-family: var(--mono);
  direction: ltr;
  unicode-bidi: isolate;
}

code {
  background: var(--bg-elevated);
  color: var(--acid);
  padding: 1px 6px;
  font-size: 0.88em;
  border: 1px solid var(--line);
  border-radius: 2px;
}

/* ============================================================
   HERO — landing page
   ============================================================ */

.hero {
  padding: 80px 64px 60px;
  border-bottom: 1px solid var(--line);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background:
    radial-gradient(circle at 20% 30%, rgba(0, 255, 136, 0.08) 0%, transparent 40%),
    radial-gradient(circle at 80% 70%, rgba(0, 217, 255, 0.06) 0%, transparent 40%);
  pointer-events: none;
}
.hero > * { position: relative; }

.hero-meta {
  display: flex;
  gap: 18px;
  margin-bottom: 24px;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--fg-dim);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  flex-wrap: wrap;
}
.hero-meta .tag {
  padding: 4px 10px;
  border: 1px solid var(--line);
  background: var(--bg-panel);
  color: var(--fg-muted);
}
.hero-meta .tag.live { color: var(--acid); border-color: var(--acid-dim); }
.hero-meta .tag.cls  { color: var(--red); border-color: var(--red-dim); }

.hero h1 {
  font-size: clamp(40px, 5.5vw, 76px);
  font-weight: 800;
  line-height: 1.05;
  margin: 0 0 16px;
}
.hero h1 .accent { color: var(--acid); }
.hero h1 .glitch {
  position: relative;
  display: inline-block;
}
.hero h1 .glitch::before,
.hero h1 .glitch::after {
  content: attr(data-text);
  position: absolute; top: 0; left: 0;
  width: 100%; height: 100%;
  pointer-events: none;
  opacity: 0.7;
}
.hero h1 .glitch::before {
  color: var(--cyan);
  transform: translate(2px, 0);
  mix-blend-mode: screen;
  clip-path: inset(0 0 60% 0);
  animation: glitch-a 4s infinite steps(8, end);
}
.hero h1 .glitch::after {
  color: var(--red);
  transform: translate(-2px, 0);
  mix-blend-mode: screen;
  clip-path: inset(60% 0 0 0);
  animation: glitch-b 4s infinite steps(8, end);
}
@keyframes glitch-a {
  0%, 90%, 100% { clip-path: inset(0 0 60% 0); transform: translate(2px, 0); }
  92% { clip-path: inset(10% 0 70% 0); transform: translate(-3px, 1px); }
  94% { clip-path: inset(40% 0 20% 0); transform: translate(4px, -1px); }
  96% { clip-path: inset(0 0 80% 0); transform: translate(-2px, 2px); }
}
@keyframes glitch-b {
  0%, 90%, 100% { clip-path: inset(60% 0 0 0); transform: translate(-2px, 0); }
  92% { clip-path: inset(70% 0 5% 0); transform: translate(3px, -1px); }
  94% { clip-path: inset(20% 0 50% 0); transform: translate(-4px, 1px); }
  96% { clip-path: inset(80% 0 0 0); transform: translate(2px, -2px); }
}

.hero .lede {
  font-size: 20px;
  color: var(--fg-muted);
  max-width: 780px;
  line-height: 1.7;
}

/* ============================================================
   PANELS / CARDS / CALLOUTS
   ============================================================ */

.panel {
  background: var(--bg-panel);
  border: 1px solid var(--line);
  padding: 22px 26px;
  margin: 22px 0;
  position: relative;
}
.panel.bracket::before,
.panel.bracket::after {
  content: "";
  position: absolute;
  width: 14px; height: 14px;
  border: 1px solid var(--acid);
}
.panel.bracket::before { top: -1px; right: -1px; border-bottom: none; border-left: none; }
.panel.bracket::after  { bottom: -1px; left: -1px;  border-top: none; border-right: none; }

.callout {
  margin: 24px 0;
  padding: 16px 22px 16px 22px;
  background: var(--bg-panel);
  border-right: 3px solid var(--acid);
  border-left: 1px solid var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  position: relative;
}
.callout.warn { border-right-color: var(--amber); }
.callout.danger { border-right-color: var(--red); }
.callout.info { border-right-color: var(--cyan); }

.callout .label {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--acid);
  margin-bottom: 6px;
  display: flex; align-items: center; gap: 8px;
}
.callout.warn .label { color: var(--amber); }
.callout.danger .label { color: var(--red); }
.callout.info .label { color: var(--cyan); }

.callout p:last-child { margin-bottom: 0; }

/* ============================================================
   TABLES
   ============================================================ */

table {
  width: 100%;
  border-collapse: collapse;
  margin: 22px 0;
  font-size: 14px;
  background: var(--bg-panel);
  border: 1px solid var(--line);
}
th {
  background: var(--bg-elevated);
  color: var(--acid);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  text-align: right;
  padding: 12px 16px;
  border-bottom: 1px solid var(--line-strong);
}
td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--line-faint);
  vertical-align: top;
  color: var(--fg-muted);
}
td:first-child { color: var(--fg); }
tr:last-child td { border-bottom: none; }
tr:hover td { background: rgba(0, 255, 136, 0.02); }

/* ============================================================
   CODE BLOCKS / TERMINAL
   ============================================================ */

pre {
  background: var(--bg-code);
  border: 1px solid var(--line);
  padding: 0;
  margin: 22px 0;
  overflow: hidden;
  font-family: var(--mono);
  font-size: 13.5px;
  line-height: 1.65;
  position: relative;
}
pre .term-head {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 14px;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--line);
  font-size: 11px;
  color: var(--fg-dim);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
pre .term-head::before {
  content: "● ● ●";
  color: var(--fg-dim);
  letter-spacing: 2px;
  font-size: 8px;
}
pre .term-head .tt {
  color: var(--acid);
  margin-right: auto;
}
pre code {
  display: block;
  padding: 18px 20px;
  background: transparent;
  border: none;
  color: var(--fg);
  white-space: pre;
  overflow-x: auto;
  direction: ltr;
  text-align: left;
}
pre code .pmt { color: var(--acid); }
pre code .cmt { color: var(--fg-dim); font-style: italic; }
pre code .kw  { color: var(--magenta); }
pre code .str { color: var(--amber); }
pre code .num { color: var(--cyan); }

/* ============================================================
   ASCII FRAMES / DIAGRAMS
   ============================================================ */

.ascii {
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1.5;
  white-space: pre;
  background: var(--bg-code);
  border: 1px solid var(--line);
  padding: 18px 22px;
  margin: 22px 0;
  color: var(--fg-muted);
  overflow-x: auto;
  direction: ltr;
  text-align: left;
}
.ascii .hl { color: var(--acid); }
.ascii .hl2 { color: var(--cyan); }
.ascii .hl3 { color: var(--amber); }

/* ============================================================
   FIGURE WRAPPER (SVG diagrams)
   ============================================================ */

figure {
  margin: 28px 0;
  background: var(--bg-panel);
  border: 1px solid var(--line);
  padding: 0;
  overflow: hidden;
}
figure .fig-head {
  padding: 10px 18px;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 11px;
  color: var(--fg-dim);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  display: flex; align-items: center; gap: 10px;
}
figure .fig-head .id {
  color: var(--acid);
}
figure .fig-body {
  padding: 28px 24px;
  display: flex;
  justify-content: center;
}
figure figcaption {
  padding: 10px 18px;
  border-top: 1px solid var(--line);
  background: var(--bg-deep);
  font-size: 13px;
  color: var(--fg-muted);
  text-align: center;
}

/* ============================================================
   KPI / STATS
   ============================================================ */

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px;
  margin: 24px 0;
}
.stat {
  border: 1px solid var(--line);
  background: var(--bg-panel);
  padding: 18px 18px;
}
.stat .v {
  font-family: var(--mono);
  font-size: 32px;
  color: var(--acid);
  font-weight: 700;
  line-height: 1;
}
.stat .k {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--fg-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-top: 8px;
}

/* ============================================================
   MODULE GRID (index)
   ============================================================ */

.modgrid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 16px;
  margin: 28px 0;
}
.modcard {
  display: block;
  background: var(--bg-panel);
  border: 1px solid var(--line);
  padding: 24px;
  border-bottom: 1px dashed var(--line);
  color: var(--fg);
  position: relative;
  transition: all 0.15s ease;
  overflow: hidden;
}
.modcard:hover {
  border-color: var(--acid-dim);
  background: var(--bg-elevated);
  transform: translateY(-2px);
}
.modcard::before {
  content: "";
  position: absolute;
  top: 0; right: 0;
  width: 60px; height: 60px;
  background:
    linear-gradient(225deg, var(--acid-dim) 0%, transparent 50%);
  opacity: 0.15;
}
.modcard .mc-num {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--acid);
  letter-spacing: 0.15em;
  margin-bottom: 12px;
  display: flex; align-items: center; gap: 8px;
}
.modcard .mc-num::after {
  content: "";
  flex: 1;
  border-top: 1px dashed var(--line-strong);
}
.modcard .mc-title {
  font-size: 22px;
  font-weight: 700;
  margin: 0 0 8px;
  color: var(--fg);
  line-height: 1.3;
}
.modcard .mc-sub {
  font-size: 13px;
  color: var(--fg-muted);
  font-family: var(--mono);
  margin-bottom: 14px;
}
.modcard .mc-desc {
  font-size: 14px;
  color: var(--fg-muted);
  line-height: 1.65;
  margin-bottom: 16px;
}
.modcard .mc-foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--fg-dim);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding-top: 14px;
  border-top: 1px solid var(--line);
}
.modcard .mc-foot .open { color: var(--acid); }
.modcard:hover .mc-foot .open::after {
  content: " ←";
}

/* ============================================================
   ANCHOR NAV (prev/next)
   ============================================================ */

.pager {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin: 60px 0 0;
  border-top: 1px solid var(--line);
  padding-top: 28px;
}
.pager a {
  display: block;
  padding: 18px 22px;
  background: var(--bg-panel);
  border: 1px solid var(--line);
  color: var(--fg);
  border-radius: 0;
  transition: all 0.15s;
}
.pager a:hover {
  border-color: var(--acid-dim);
  background: var(--bg-elevated);
}
.pager .label {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--fg-dim);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 6px;
}
.pager .title {
  font-size: 15px;
  color: var(--acid);
}
.pager .next { text-align: left; }
.pager .next .label::before { content: "→ "; }
.pager .prev .label::after  { content: " ←"; }

/* ============================================================
   EXERCISE / KEYPOINTS BOXES
   ============================================================ */

.box {
  margin: 28px 0;
  border: 1px solid var(--line);
  background: var(--bg-panel);
  padding: 22px 26px;
  position: relative;
}
.box::before {
  content: attr(data-label);
  position: absolute;
  top: -10px;
  right: 20px;
  background: var(--bg-void);
  padding: 0 10px;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--acid);
  letter-spacing: 0.15em;
  text-transform: uppercase;
}
.box.amber::before { color: var(--amber); }
.box.amber { border-color: var(--amber-dim); }

.box ol, .box ul { margin-bottom: 0; }

/* ============================================================
   BADGES
   ============================================================ */

.badge {
  display: inline-block;
  padding: 2px 8px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border: 1px solid var(--line-strong);
  color: var(--fg-muted);
  background: var(--bg-elevated);
  vertical-align: middle;
  direction: ltr;
}
.badge.ok { color: var(--acid); border-color: var(--acid-dim); }
.badge.bad { color: var(--red); border-color: var(--red-dim); }
.badge.warn { color: var(--amber); border-color: var(--amber-dim); }
.badge.info { color: var(--cyan); border-color: var(--cyan-dim); }

/* ============================================================
   TOC inside page
   ============================================================ */

.toc {
  background: var(--bg-panel);
  border: 1px solid var(--line);
  padding: 18px 26px;
  margin: 24px 0 32px;
  font-size: 14px;
}
.toc .toc-h {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--fg-dim);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 10px;
}
.toc ol { padding-right: 18px; margin: 0; }
.toc a { color: var(--fg-muted); border: none; }
.toc a:hover { color: var(--acid); }

/* ============================================================
   FOOTER
   ============================================================ */

.foot {
  border-top: 1px solid var(--line);
  margin-top: 60px;
  padding: 28px 64px;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--fg-dim);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  background: var(--bg-void);
}
.foot .sig { color: var(--acid); }

/* ============================================================
   RESPONSIVE
   ============================================================ */

@media (max-width: 1000px) {
  .shell { grid-template-columns: 1fr; }
  .sidebar { position: relative; height: auto; top: 0; }
  .main { padding: 40px 24px 80px; }
  .hero { padding: 60px 24px 40px; }
  .foot { padding: 28px 24px; }
}