* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; line-height: 1.6; min-height: 100vh; }
a { text-decoration: none; }
ul { list-style: none; }
button { cursor: pointer; border: none; background: transparent; }
img { max-width: 100%; display: block; }
section { min-height: 100vh; padding: 2rem; display: flex; flex-direction: column; align-items: center; justify-content: center; }
h1, h2, h3 { margin-bottom: 1rem; }
canvas { display: block; margin: 1rem auto; border: 1px solid var(--border-color); }