:root {
  --bg: #0f1117;
  --panel: #1a1d27;
  --border: #2c3040;
  --text: #e6e8ef;
  --muted: #9aa0b4;
  --accent: #5b8cff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Segoe UI", "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
  line-height: 1.6;
}

.container {
  max-width: 880px;
  margin: 0 auto;
  padding: 2rem 1.25rem 4rem;
}

h1 {
  margin: 0 0 0.25rem;
}

.lead {
  color: var(--muted);
  margin-top: 0;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem 1.5rem;
  margin-top: 1.5rem;
}

.panel h2 {
  margin-top: 0;
}

label {
  display: block;
  margin: 0.9rem 0 0.3rem;
  font-weight: 600;
}

input,
textarea {
  width: 100%;
  background: #11141c;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.55rem 0.7rem;
  font-size: 0.95rem;
  font-family: inherit;
}

textarea {
  resize: vertical;
  font-family: "Consolas", "Courier New", monospace;
}

button {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 0.5rem 1rem;
  font-size: 0.9rem;
  cursor: pointer;
}

button:hover {
  filter: brightness(1.1);
}

#generate {
  margin-top: 1.25rem;
  padding: 0.65rem 1.5rem;
  font-size: 1rem;
}

.errors {
  color: #ff8080;
  min-height: 1.2em;
  font-weight: 600;
}

.output {
  margin-top: 1.25rem;
}

.output-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.output-head label {
  margin: 0;
}

.output-head button {
  padding: 0.3rem 0.8rem;
  background: transparent;
  border: 1px solid var(--accent);
  color: var(--accent);
}