@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500;700&display=swap');

:root {
  --bg-dark: #1b2b2b;
  --text-dark: #e0f0f0;
  --card-dark: #283a3a;
  --border-dark: #4a5c5c;

  --bg-light: #dce7e7;
  --text-light: #1b2b2b;
  --card-light: #ffffff;
  --border-light: #ccc;

  --accent: #2e8b57;
  --accent-hover: #256b45;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Segoe UI", Roboto, Arial, sans-serif;
}

body {
  min-height: 100vh;
  transition: background 0.5s ease, color 0.5s ease;
  line-height: 1.6;
}

body.dark {
  background: var(--bg-dark);
  color: var(--text-dark);
}

body.light {
  background: var(--bg-light);
  color: var(--text-light);
}

header {
  padding: 20px 30px;
  border-bottom: 1px solid;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

body.dark header {
  border-color: var(--border-dark);
}

body.light header {
  border-color: var(--border-light);
}

header h1 {
  font-size: 1.6rem;
  font-weight: 500;
}

button {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 0.9rem;
  color: inherit;
  opacity: 0.8;
}

button:hover {
  opacity: 1;
}

main {
  max-width: 800px;
  margin: 40px auto;
  padding: 0 20px;
}

.card {
  padding: 25px 30px;
  border-radius: 10px;
  border: 1px solid;
  margin-bottom: 25px;
}

body.dark .card {
  background: var(--card-dark);
  border-color: var(--border-dark);
}

body.light .card {
  background: var(--card-light);
  border-color: var(--border-light);
}

h2 {
  font-size: 1.2rem;
  margin-bottom: 10px;
  color: var(--accent);
}

ul {
  padding-left: 20px;
  margin-top: 10px;
}

li {
  margin-bottom: 8px;
}

.warn {
  color: #ffb3b3;
  font-weight: 500;
}

.footer {
  text-align: center;
  opacity: 0.6;
  font-size: 0.85rem;
  margin-top: 40px;
}