:root{--color-primary: #000;--color-secondary: #9e9e9e;--color-border: #d0d0d0;--font-size-small: 12px;--font-size-medium: 16px;--font-size-large: 28px}*{box-sizing:border-box}body{margin:0;font-family:sans-serif;color:var(--color-primary)}.app{max-width:960px;margin:0 auto;padding:32px 16px 64px}.app h1{margin:0 0 8px;font-size:1.75rem;font-weight:700}.app>p{margin:0 0 32px;font-size:1rem;font-weight:400;color:var(--color-secondary)}.app section{margin:0 0 32px;padding:16px;border:1px solid var(--color-border);border-radius:8px}.app section h2{margin:0 0 16px;font-size:1rem;font-weight:700}.app section p{margin:8px 0 0;font-size:1rem;font-weight:400;color:var(--color-secondary)}.demo-block{display:grid;gap:8px}