/* Минималистичный чёрно-белый стиль */
:root {
  --ink: #111;
  --paper: #fff;
  --muted: #767676;
  --line: #e2e2e2;
  --soft: #f6f6f6;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font: 16px/1.55 "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--paper);
  max-width: 860px;
  margin: 0 auto;
  padding: 24px 20px 60px;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  padding-bottom: 20px;
  border-bottom: 2px solid var(--ink);
}
.brand { display: flex; gap: 14px; align-items: flex-start; }
.logo { font-size: 28px; line-height: 1.2; }
h1 { font-size: 22px; letter-spacing: -0.3px; }
.sub { color: var(--muted); font-size: 13px; margin-top: 2px; }

.lang-switch { display: flex; border: 1px solid var(--ink); flex: 0 0 auto; }
.lang-switch button {
  background: var(--paper);
  color: var(--ink);
  border: none;
  padding: 6px 14px;
  font: inherit;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
}
.lang-switch button.active { background: var(--ink); color: var(--paper); }

.examples { margin: 24px 0 8px; }
.examples-label { font-size: 13px; color: var(--muted); margin-bottom: 8px; }
#examples { display: flex; flex-wrap: wrap; gap: 8px; }
.example-chip {
  border: 1px solid var(--line);
  background: var(--soft);
  padding: 7px 12px;
  font-size: 13px;
  cursor: pointer;
  transition: border-color .15s;
}
.example-chip:hover { border-color: var(--ink); }

.ask { display: flex; gap: 10px; margin: 16px 0 28px; align-items: stretch; }
#question {
  flex: 1;
  font: inherit;
  padding: 12px 14px;
  border: 1px solid var(--ink);
  resize: vertical;
  min-height: 52px;
}
#question:focus { outline: 2px solid var(--ink); outline-offset: -1px; }
#send {
  background: var(--ink);
  color: var(--paper);
  border: 1px solid var(--ink);
  padding: 0 22px;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  flex: 0 0 auto;
}
#send:disabled { opacity: .45; cursor: default; }

.pipeline { border: 1px solid var(--line); margin-bottom: 28px; }
.step { border-bottom: 1px solid var(--line); }
.step:last-child { border-bottom: none; }
.step-head {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 12px 16px;
}
.step-dot {
  width: 10px; height: 10px;
  border: 1.5px solid var(--muted);
  border-radius: 50%;
  flex: 0 0 auto;
  align-self: center;
}
.step.active .step-dot { border-color: var(--ink); animation: pulse 1s infinite alternate; }
.step.done .step-dot { background: var(--ink); border-color: var(--ink); }
@keyframes pulse { from { transform: scale(.8); } to { transform: scale(1.25); } }
.step-name { font-weight: 600; font-size: 14px; white-space: nowrap; }
.step-desc { color: var(--muted); font-size: 13px; }
.step.active .step-desc { color: var(--ink); }
.step-body {
  padding: 0 16px 14px 36px;
  font-size: 13px;
  color: #333;
  word-break: break-word;
}
.step-body h3 { font-size: 13px; margin: 10px 0 4px; }
.step-body ul { margin: 6px 0 6px 18px; }
.step-body p { margin: 6px 0; }
.step-body code {
  display: block;
  background: var(--soft);
  border: 1px solid var(--line);
  padding: 8px 10px;
  margin-top: 6px;
  font-size: 12px;
  overflow-x: auto;
  white-space: pre;
}

.answer {
  border: 2px solid var(--ink);
  padding: 22px 26px;
}
.answer h3 { margin: 14px 0 8px; font-size: 16px; }
.answer h3:first-child { margin-top: 0; }
.answer ul { margin: 8px 0 8px 22px; }
.answer li { margin: 4px 0; }
.answer p { margin: 8px 0; }

.error {
  border: 1px solid var(--ink);
  background: var(--soft);
  padding: 12px 16px;
  font-size: 14px;
}

footer {
  margin-top: 40px;
  color: var(--muted);
  font-size: 12px;
  border-top: 1px solid var(--line);
  padding-top: 12px;
}

.hidden { display: none; }

@media (max-width: 560px) {
  header { flex-direction: column; }
  .lang-switch { align-self: flex-end; }
  .ask { flex-direction: column; }
  #send { padding: 12px; }
  .step-head { flex-wrap: wrap; }
}