/* reset */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #0a0a0a;
  --fg: #c8c8c8;
  --dim: #666;
  --accent: #e8e8e8;
  --border: #222;
  --code-bg: #111;
  --green: #5f9f5f;
  --amber: #b5a642;
}

html {
  font-size: 15px;
}

body {
  font-family: 'IBM Plex Mono', 'SF Mono', 'Consolas', monospace;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

main {
  max-width: 680px;
  margin: 0 auto;
  padding: 3rem 1.5rem 4rem;
}

/* header */
header {
  margin-bottom: 3rem;
}

.logo {
  font-size: 0.75rem;
  line-height: 1.2;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.tagline {
  color: var(--dim);
  font-size: 0.85rem;
}

/* sections */
section {
  margin-bottom: 3rem;
}

h2 {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  color: var(--dim);
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.4rem;
  margin-bottom: 1.2rem;
  text-transform: uppercase;
}

p {
  margin-bottom: 0.8rem;
  font-size: 0.9rem;
}

a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid var(--border);
  transition: border-color 0.15s;
}

a:hover {
  border-color: var(--accent);
}

strong {
  color: var(--accent);
  font-weight: 600;
}

code {
  background: var(--code-bg);
  padding: 0.1em 0.35em;
  border-radius: 2px;
  font-size: 0.85rem;
}

/* pipeline */
.pipeline-flow {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.step {
  border-left: 2px solid var(--border);
  padding: 0.8rem 0 0.8rem 1.2rem;
  position: relative;
}

.step-num {
  position: absolute;
  left: -0.65rem;
  top: 0.8rem;
  background: var(--bg);
  color: var(--dim);
  font-size: 0.75rem;
  width: 1.3rem;
  height: 1.3rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
  border-radius: 50%;
}

.step-name {
  font-weight: 600;
  color: var(--accent);
  font-size: 0.9rem;
}

.step-perm {
  font-size: 0.7rem;
  color: var(--dim);
  margin-left: 0.75rem;
  border: 1px solid var(--border);
  padding: 0.1em 0.4em;
  border-radius: 2px;
}

.step p {
  margin-top: 0.3rem;
  margin-bottom: 0;
  font-size: 0.8rem;
  color: var(--dim);
}

.arrow {
  display: none;
}

.result {
  border-left: 2px solid var(--green);
  padding: 0.6rem 1.2rem;
  color: var(--green);
  font-size: 0.85rem;
  font-weight: 600;
  position: relative;
}

.result::before {
  content: '';
  position: absolute;
  left: -0.35rem;
  top: 50%;
  transform: translateY(-50%);
  width: 0.7rem;
  height: 0.7rem;
  background: var(--green);
  border-radius: 50%;
}

/* diagram */
.diagram {
  font-size: 0.72rem;
  line-height: 1.4;
  color: var(--dim);
  overflow-x: auto;
  padding: 1rem;
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 3px;
}

/* architecture grid */
.arch-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
}

.arch-item {
  padding: 1rem;
  background: var(--bg);
}

.arch-item h3 {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 0.4rem;
}

.arch-item p {
  font-size: 0.78rem;
  color: var(--dim);
  margin-bottom: 0;
}

/* feature list */
ul {
  list-style: none;
  padding: 0;
}

li {
  font-size: 0.85rem;
  padding: 0.4rem 0;
  padding-left: 1.2rem;
  position: relative;
  border-bottom: 1px solid var(--border);
}

li:last-child {
  border-bottom: none;
}

li::before {
  content: '~';
  position: absolute;
  left: 0;
  color: var(--dim);
}

/* code block */
.code-block {
  font-size: 0.8rem;
  line-height: 1.6;
  padding: 1.2rem;
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 3px;
  overflow-x: auto;
}

.code-block .comment {
  color: var(--dim);
}

.note {
  font-size: 0.78rem;
  color: var(--dim);
  margin-top: 0.6rem;
}

/* footer */
footer {
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
  text-align: center;
}

.footer-links {
  margin-bottom: 0.5rem;
}

.footer-links a {
  font-size: 0.8rem;
}

.sep {
  color: var(--border);
  margin: 0 0.5rem;
}

.license {
  font-size: 0.7rem;
  color: var(--dim);
}

/* responsive */
@media (max-width: 500px) {
  html {
    font-size: 14px;
  }

  main {
    padding: 2rem 1rem 3rem;
  }

  .logo {
    font-size: 0.6rem;
  }

  .arch-grid {
    grid-template-columns: 1fr;
  }

  .diagram {
    font-size: 0.6rem;
  }
}