:root {
  --bg: #f4f7fb;
  --card: #ffffff;
  --text: #1a2a3a;
  --muted: #4a5d70;
  --accent: #0b84ff;
  --accent-hover: #0869cc;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #eef4ff, #f7fbff 60%, #ffffff);
  color: var(--text);
}

.container {
  width: min(90vw, 680px);
  background: var(--card);
  border: 1px solid #dce8f5;
  border-radius: 14px;
  padding: 2rem;
  box-shadow: 0 10px 30px rgba(11, 132, 255, 0.08);
}

h1 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

p {
  margin-top: 0;
  line-height: 1.6;
  color: var(--muted);
}

button {
  border: 0;
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  padding: 0.7rem 1rem;
  cursor: pointer;
  transition: background 0.2s ease;
}

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

.message {
  margin-top: 1rem;
  min-height: 1.2rem;
  color: var(--text);
  font-weight: 500;
}