:root {
  --bg-color: #f9fafb;
  --card-bg: #ffffff;
  --text-primary: #111827;
  --text-secondary: #4b5563;
  --border-color: #e5e7eb;
  --primary-btn: #ef4444;
  --primary-hover: #dc2626;
}

body {
  margin: 0;
  font-family: 'Inter', sans-serif;
  background-color: var(--bg-color);
  color: var(--text-primary);
  display: flex;
  justify-content: center;
  padding: 2rem;
}

.container {
  width: 100%;
  max-width: 600px;
  background: var(--card-bg);
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05), 0 10px 15px rgba(0, 0, 0, 0.1);
}

header {
  margin-bottom: 1.5rem;
  text-align: center;
}

h1 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

textarea {
  width: 100%;
  height: 200px;
  padding: 1rem;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-family: monospace;
  resize: vertical;
  margin-bottom: 1rem;
  box-sizing: border-box;
}

button {
  width: 100%;
  padding: 0.75rem;
  background-color: var(--primary-btn);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.2s;
}

button:hover {
  background-color: var(--primary-hover);
}

button:disabled {
  background-color: #fca5a5;
  cursor: not-allowed;
}

.hidden {
  display: none !important;
}

#results {
  margin-top: 2rem;
  border-top: 1px solid var(--border-color);
  padding-top: 1.5rem;
}

.result-item {
  display: flex;
  flex-direction: column;
  padding: 1rem;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  margin-bottom: 1rem;
  background: var(--bg-color);
}

.result-title {
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.result-link {
  font-size: 0.85rem;
  color: var(--text-secondary);
  word-break: break-all;
  margin-bottom: 0.75rem;
}

.status {
  display: inline-block;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
}

.status.alive {
  background-color: #d1fae5;
  color: #065f46;
}

.status.dead {
  background-color: #fee2e2;
  color: #991b1b;
}

.status.loading {
  background-color: #fef3c7;
  color: #92400e;
}

.status.invalid {
  background-color: #f3f4f6;
  color: #4b5563;
}