:root {
  --bg: #f3f1ea;
  --card: #ffffff;
  --text: #1a2e28;
  --muted: #5f7268;
  --line: #d5ddd4;
  --accent: #1f5c48;
  --accent-soft: #e7efe9;
  --warm: #c4733a;
  --ok: #2d6b45;
  --err: #943f31;
  --sans: "Source Sans 3", "Segoe UI", system-ui, sans-serif;
  --mono: "Source Code Pro", ui-monospace, Consolas, monospace;
  --radius: 14px;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
  min-height: 100vh;
}
.shell-b-top {
  max-width: 1180px;
  margin: 0 auto;
  padding: 2rem 1.75rem 1.25rem;
  position: relative;
}
.shell-b-brand {
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.55rem;
  text-transform: uppercase;
  color: var(--muted);
}
.shell-b-mark {
  font-size: 1.35rem;
  color: var(--accent);
  letter-spacing: 0;
  font-weight: 800;
}
.shell-b-privacy {
  position: absolute;
  top: 2.1rem;
  right: 1.75rem;
  font-size: 0.78rem;
  color: var(--muted);
  text-decoration: none;
}
.shell-b-privacy span { color: var(--ok); font-size: 0.55rem; margin-right: 0.35rem; }
.shell-b-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin: 1.1rem 0 0;
}
.shell-b-nav a {
  color: var(--accent);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 600;
}
.shell-b-nav a[aria-current="page"] {
  background: var(--accent-soft);
  padding: 0.2rem 0.55rem;
  border-radius: 999px;
}
.shell-b-top h1 {
  margin: 1.35rem 0 0.65rem;
  font-size: clamp(2rem, 4.5vw, 3.1rem);
  font-weight: 650;
  letter-spacing: -0.045em;
  line-height: 1.08;
  max-width: 18ch;
}
.shell-b-top h1 span { color: var(--warm); }
.shell-b-intro {
  margin: 0;
  max-width: 38rem;
  color: var(--muted);
  font-size: 1.02rem;
}
.shell-b-workspace {
  max-width: 1180px;
  margin: 1.25rem auto 2rem;
  padding: 0 1.75rem;
  display: grid;
  grid-template-columns: 1fr 1fr;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--card);
  box-shadow: 0 12px 40px rgba(26, 46, 40, 0.06);
}
.shell-b-panel { padding: 1.35rem 1.4rem; min-width: 0; }
.shell-b-in { border-right: 1px solid var(--line); }
.shell-b-out { background: #f7faf6; }
.shell-b-panel h2 {
  margin: 0;
  font-size: 0.95rem;
  font-weight: 650;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.shell-b-panel .step {
  color: var(--muted);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
textarea {
  display: block;
  width: 100%;
  min-height: 260px;
  margin-top: 0.85rem;
  resize: vertical;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--text);
  padding: 0.9rem 1rem;
  font: 0.82rem/1.65 var(--mono);
}
.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.9rem;
}
button, .file-button {
  font-family: inherit;
  font-size: 0.8rem;
  font-weight: 650;
  border: 1px solid var(--line);
  border-radius: 8px;
  cursor: pointer;
  background: transparent;
  color: var(--accent);
  padding: 0.55rem 0.9rem;
  min-height: 2.4rem;
}
button.primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
button.primary:hover { filter: brightness(1.06); }
.out-card {
  margin-top: 0.75rem;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.85rem 1rem;
}
.out-card pre {
  margin: 0;
  white-space: pre-wrap;
  word-break: break-all;
  font-family: var(--mono);
  font-size: 0.78rem;
}
.notes {
  max-width: 1180px;
  margin: 0 auto 2rem;
  padding: 0 1.75rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}
.notes h2 { font-size: 0.85rem; margin: 0 0 0.35rem; }
.notes p { margin: 0; font-size: 0.82rem; color: var(--muted); line-height: 1.7; }
footer {
  max-width: 1180px;
  margin: 0 auto;
  padding: 1rem 1.75rem 2rem;
  border-top: 1px solid var(--line);
  font-size: 0.75rem;
  color: var(--muted);
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}
footer a { color: var(--accent); }
.prose { max-width: 720px; margin: 0 auto; padding: 1.5rem 1.75rem 3rem; }
.prose h2 { margin-top: 1.5rem; }
.prose p, .prose li { color: var(--muted); }
@media (max-width: 800px) {
  .shell-b-workspace { grid-template-columns: 1fr; }
  .shell-b-in { border-right: 0; border-bottom: 1px solid var(--line); }
  .shell-b-privacy { position: static; display: inline-block; margin-top: 0.5rem; }
  .notes { grid-template-columns: 1fr; }
  .shell-b-top h1 { max-width: none; }
}