:root {
  --bg: #11151c;
  --sur: #131720;
  --bdr: #1e2535;
  --acc: #f0c040;
  --acc2: #4fc3f7;
  --txt: #c8d0e0;
  --mut: #5a6a88;
}
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
body {
  background: var(--bg);
  color: var(--txt);
  font-family: "DM Mono", monospace;
  font-size: 14px;
  line-height: 1.7;
  max-width: 740px;
  margin: 0 auto;
  padding: 0 1.5rem 3rem;
}
a {
  color: var(--mut);
  text-decoration: none;
  transition: color 0.2s;
}
a:hover {
  color: var(--acc);
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
  border-bottom: 1px solid var(--bdr);
  margin-bottom: 2.5rem;
}
.logo {
  font-family: "Syne", sans-serif;
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--acc);
}
nav {
  display: flex;
  gap: 1.25rem;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

h1 {
  font-family: "Syne", sans-serif;
  font-size: 2.6rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 0.6rem;
}
h1 em {
  color: var(--acc);
  font-style: normal;
}
h2 {
  font-family: "Syne", sans-serif;
  font-size: 1.15rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 0.6rem;
}
p {
  color: var(--txt);
  margin-bottom: 0.8rem;
  font-size: 0.88rem;
}
section {
  margin-bottom: 2.5rem;
}
.label {
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--acc2);
  margin-bottom: 0.3rem;
}
hr {
  border: none;
  border-top: 1px solid var(--bdr);
  margin: 2rem 0;
}

/* CODE */
pre {
  background: #0d1117;
  border: 1px solid var(--bdr);
  border-radius: 8px;
  padding: 1rem 1.2rem;
  font-size: 0.8rem;
  overflow-x: auto;
  margin: 1rem 0;
}
.kw {
  color: #c792ea;
}
.fn {
  color: var(--acc2);
}
.cm {
  color: #455a64;
  font-style: italic;
}
.nb {
  color: #f78c6c;
}
.op {
  color: var(--acc);
}

details {
  background: var(--sur);
  border: 1px solid var(--bdr);
  border-radius: 8px;
  margin-bottom: 0.75rem;
}
details:hover {
  border-color: rgba(240, 192, 64, 0.3);
}
summary {
  padding: 0.8rem 1rem;
  cursor: pointer;
  list-style: none;
  font-family: "Syne", sans-serif;
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--acc);
  display: flex;
  justify-content: space-between;
}
summary::after {
  content: "+";
  color: var(--mut);
}
details[open] summary::after {
  content: "−";
}
.db {
  padding: 0.75rem 1rem;
  font-size: 0.82rem;
  color: var(--mut);
  border-top: 1px solid var(--bdr);
}

/* FIGURE */
figure {
  border: 1px solid var(--bdr);
  border-radius: 8px;
  overflow: hidden;
  margin: 1.5rem 0;
}
.fv {
  background: #0d1117;
  display: flex;
  gap: 1rem;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  flex-wrap: wrap;
}
.box {
  border: 1px solid var(--bdr);
  border-radius: 6px;
  padding: 0.6rem 1rem;
  text-align: center;
  min-width: 110px;
}
.box .bl {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--mut);
}
.box .bv {
  font-family: "Syne", sans-serif;
  font-size: 1rem;
  font-weight: 700;
}
.box.a {
  border-color: rgba(167, 139, 250, 0.5);
}
.box.a .bv {
  color: #a78bfa;
}
.box.b {
  border-color: rgba(79, 195, 247, 0.5);
}
.box.b .bv {
  color: var(--acc2);
}
.box.c {
  border-color: rgba(240, 192, 64, 0.5);
}
.box.c .bv {
  color: var(--acc);
}
.arr {
  color: var(--mut);
  font-size: 1.2rem;
}
figcaption {
  padding: 0.65rem 1rem;
  font-size: 0.75rem;
  color: var(--mut);
  border-top: 1px solid var(--bdr);
}
figcaption::before {
  content: "Fig. ";
  color: var(--acc);
}

/* FOOTER */
footer {
  border-top: 1px solid var(--bdr);
  padding-top: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-size: 0.75rem;
  color: var(--mut);
}
footer .fl {
  font-family: "Syne", sans-serif;
  font-weight: 800;
  color: var(--acc);
}