*,
*::before,
*::after {
  box-sizing: border-box;
}

:root {
  --bg: #020617;
  --card-bg: #ffffff;
  --accent: #2563eb;
  --accent-soft: rgba(37, 99, 235, 0.12);
  --border: #e2e8f0;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --radius-lg: 18px;
  --shadow-soft: 0 20px 50px rgba(15, 23, 42, 0.45);
  --font-main: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
  sans-serif;
  --transition: 0.2s ease;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-main);
  background: radial-gradient(circle at top, #1e293b 0, #020617 55%, #020617);
  color: var(--text-main);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.page {
  width: 100%;
  max-width: 960px;
}

.card {
  background-color: var(--card-bg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  padding: 24px 24px 20px;
}

.card-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 18px;
}

.icon {
  font-weight: 700;
  font-size: 1.4rem;
  padding: 8px 12px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
}

.card-header h1 {
  margin: 0;
  font-size: 1.6rem;
}

.subtitle {
  margin: 4px 0 0;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.layout {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.panel h2 {
  margin: 0 0 4px;
  font-size: 1rem;
}

.hint {
  margin: 0 0 6px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

textarea {
  width: 100%;
  min-height: 220px;
  resize: vertical;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas,
  "Liberation Mono", "Courier New", monospace;
  font-size: 0.86rem;
  border-radius: 14px;
  border: 1px solid var(--border);
  padding: 10px 12px;
  outline: none;
  background: #f8fafc;
  transition: border-color var(--transition), box-shadow var(--transition),
  background-color var(--transition);
}

textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px rgba(37, 99, 235, 0.35);
  background: #ffffff;
}

.controls {
  margin-top: 16px;
}

.status {
  font-size: 0.85rem;
  margin-bottom: 8px;
  padding: 8px 10px;
  border-radius: 999px;
  background: #f1f5f9;
  color: var(--text-muted);
}

.status.ok {
  background: #ecfdf3;
  color: #15803d;
}

.status.error {
  background: #fef2f2;
  color: #b91c1c;
}

.buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.primary-btn,
.secondary-btn,
.ghost-btn {
  border-radius: 999px;
  border: none;
  cursor: pointer;
  font: inherit;
  padding: 9px 16px;
  transition: background-color var(--transition), transform var(--transition),
  box-shadow var(--transition), color var(--transition), border-color var(--transition);
}

.primary-btn {
  background: var(--accent);
  color: #ffffff;
}

.primary-btn:hover {
  background: #1d4ed8;
  box-shadow: 0 10px 25px rgba(37, 99, 235, 0.45);
  transform: translateY(-1px);
}

.secondary-btn {
  background: #e2e8f0;
  color: #0f172a;
}

.secondary-btn:hover {
  background: #cbd5f5;
}

.ghost-btn {
  background: transparent;
  border: 1px solid #e2e8f0;
  color: var(--text-muted);
}

.ghost-btn:hover {
  border-color: #cbd5f5;
  background: #f8fafc;
}

.footer-note {
  margin-top: 10px;
  font-size: 0.78rem;
  color: var(--text-muted);
  text-align: center;
}

/* responsive */
@media (max-width: 768px) {
  .layout {
    grid-template-columns: minmax(0, 1fr);
  }

  textarea {
    min-height: 180px;
  }

  .card {
    padding: 20px 18px 16px;
  }
}