:root { --max: 900px; }
* { box-sizing: border-box; }
body { margin: 0; font-family: system-ui, -apple-system, Segoe UI, Roboto, sans-serif; line-height: 1.6; }
header { background: #030303; color: #fff; padding: 1rem; }
header nav a { color: #68aa8b; margin-right: 1rem; text-decoration: none; }
.container { max-width: var(--max); margin: 0 auto; padding: 1rem; }
main h2 { margin-top: 2rem; }
ul { padding-left: 1.25rem; }
input, textarea, button { width: 100%; padding: .75rem; margin: .5rem 0; }
button { cursor: pointer; }
.note { color: rgb(255, 255, 255); font-size: .9rem; }
img { max-width: 300px;   /* or any size you prefer */
  width: 100%;
  height: auto;
  display: block;
  margin: 0 auto;
}