:root {
  --bg: #0f1420;
  --card-bg: #171d2b;
  --border: #262f42;
  --text: #e7ebf3;
  --muted: #8b95ab;
  --accent: #4f7cff;
  --accent-hover: #3d67f0;
  --ok: #34c98f;
  --ok-bg: rgba(52, 201, 143, 0.12);
  --err: #ef5a6f;
  --err-bg: rgba(239, 90, 111, 0.12);
  --radius: 14px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(circle at top, #161c2c 0%, var(--bg) 60%);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.page {
  width: 100%;
  max-width: 480px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.header {
  text-align: center;
}

.header h1 {
  margin: 0 0 4px;
  font-size: 1.9rem;
  letter-spacing: -0.02em;
}

.subtitle {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}

.section h2 {
  margin: 0 0 6px;
  font-size: 1.1rem;
}

.hint {
  margin: 0 0 18px;
  color: var(--muted);
  font-size: 0.9rem;
}

.btn {
  width: 100%;
  padding: 12px 18px;
  border: none;
  border-radius: 10px;
  background: var(--accent);
  color: white;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s ease, transform 0.1s ease;
}

.btn:hover {
  background: var(--accent-hover);
}

.btn:active {
  transform: scale(0.98);
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.result {
  margin-top: 18px;
  padding: 14px 16px;
  border-radius: 10px;
  font-size: 0.88rem;
  line-height: 1.5;
  word-break: break-word;
}

.result--idle {
  background: rgba(255, 255, 255, 0.04);
  border: 1px dashed var(--border);
  color: var(--muted);
}

.result--loading {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  color: var(--muted);
}

.result--ok {
  background: var(--ok-bg);
  border: 1px solid rgba(52, 201, 143, 0.35);
  color: var(--ok);
}

.result--error {
  background: var(--err-bg);
  border: 1px solid rgba(239, 90, 111, 0.35);
  color: var(--err);
}

.result pre {
  margin: 8px 0 0;
  white-space: pre-wrap;
  font-family: "SF Mono", Consolas, Monaco, monospace;
  font-size: 0.82rem;
  color: var(--text);
}

.footer {
  text-align: center;
  color: var(--muted);
  font-size: 0.78rem;
}