:root {
  --text: #333;
  --muted: #666;
  --border: #ddd;
  --card: #fff;
  --page: #fafafa;
  --primary: #007bff;
  --primary-hover: #0056b3;
  --secondary: #28a745;
  --secondary-hover: #1e7e34;
  --ok: #1e7e34;
  --error: #c62828;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--text);
  background: var(--page);
}

main {
  max-width: 640px;
  margin: 0 auto;
  padding: 48px 16px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

h1 {
  margin: 0;
  font-size: 24px;
  text-align: center;
  overflow-wrap: anywhere;
}

h2 {
  margin: 0 0 12px;
  font-size: 18px;
}

.card {
  padding: 20px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

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

input {
  flex: 1 1 220px;
  min-width: 0;
  padding: 10px;
  font-size: 16px;
  border: 1px solid #ccc;
  border-radius: 4px;
}

button {
  padding: 10px 16px;
  font-size: 16px;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  color: #fff;
}

button:disabled {
  opacity: 0.6;
  cursor: wait;
}

button.primary {
  background: var(--primary);
}

button.primary:hover:not(:disabled) {
  background: var(--primary-hover);
}

button.secondary {
  background: var(--secondary);
}

button.secondary:hover:not(:disabled) {
  background: var(--secondary-hover);
}

button.link {
  padding: 10px 4px;
  color: var(--primary);
  background: none;
  text-decoration: underline;
}

.result {
  margin-top: 12px;
  overflow-wrap: anywhere;
}

.result:empty {
  display: none;
}

.result ul {
  margin: 4px 0 0;
  padding-left: 20px;
}

.result .ok {
  color: var(--ok);
}

.result .error {
  color: var(--error);
}

.result .muted {
  color: var(--muted);
}

.result table {
  width: 100%;
  border-collapse: collapse;
}

.result th,
.result td {
  padding: 8px;
  border: 1px solid var(--border);
  text-align: left;
}

.result th {
  width: 35%;
  background: #f4f4f4;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}