:root {
  --bg: #f8fafc;
  --card: #ffffff;
  --primary: #2563eb;
  --primary-hover: #1e40af;
  --text: #111827;
  --muted: #6b7280;
  --border: #e5e7eb;
  --radius: 14px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  font-family: "Inter", system-ui, sans-serif;
  color: var(--text);
}

.shell {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.card {
  width: 100%;
  max-width: 520px;
  background: var(--card);
  padding: 40px;
  border-radius: 20px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
}

h1 {
  margin: 0 0 6px 0;
  font-size: 1.9rem;
  font-weight: 700;
  text-align: center;
}

.subtitle {
  text-align: center;
  color: var(--muted);
  margin-bottom: 32px;
  font-size: 0.95rem;
}

.input-row {
  display: flex;
  gap: 10px;
}

input[type="url"] {
  flex: 1;
  height: 52px;
  padding: 0 16px;
  font-size: 0.95rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  transition: border-color 0.2s, box-shadow 0.2s;
}

input[type="url"]:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.15);
}

button {
  height: 52px;
  padding: 0 22px;
  border-radius: var(--radius);
  border: none;
  font-size: 0.95rem;
  font-weight: 600;
  background: var(--primary);
  color: #ffffff;
  cursor: pointer;
  transition: background 0.2s, transform 0.05s;
}

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

button:active {
  transform: translateY(1px);
}

/* Result container (used by your JS as-is) */
.result {
  margin-top: 28px;
  padding: 18px;
  background: #f1f5f9;
  border-radius: var(--radius);
  font-size: 0.95rem;
  text-align: center;
}

.result a {
  color: var(--primary);
  font-weight: 600;
  text-decoration: none;
}

.result a:hover {
  text-decoration: underline;
}