:root {
    --color-bg: #ffffff;
    --color-text: #1a1a1a;
    --color-muted: #666666;
    --color-border: #e5e5e5;
    --color-link: #0066cc;
    --color-link-hover: #004999;
    --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, sans-serif;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 0;
    font-family: var(--font-stack);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.6;
}

.container {
    max-width: 720px;
    margin: 0 auto;
    padding: 48px 24px;
}

header {
    margin-bottom: 48px;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--color-border);
}

h1 {
    font-size: 2rem;
    margin: 0 0 8px 0;
    font-weight: 600;
}

h2 {
    font-size: 1.25rem;
    margin: 0 0 16px 0;
    font-weight: 600;
}

.subtitle {
    color: var(--color-muted);
    margin: 0;
}

.prototype-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.prototype-list li {
    padding: 16px 0;
    border-bottom: 1px solid var(--color-border);
}

.prototype-list li:last-child {
    border-bottom: none;
}

.prototype-list a {
    color: var(--color-link);
    text-decoration: none;
    font-weight: 500;
    display: block;
    margin-bottom: 4px;
}

.prototype-list a:hover {
    color: var(--color-link-hover);
    text-decoration: underline;
}

.description {
    color: var(--color-muted);
    font-size: 0.9rem;
}

footer {
    margin-top: 48px;
    padding-top: 24px;
    border-top: 1px solid var(--color-border);
    color: var(--color-muted);
    font-size: 0.9rem;
}

footer a {
    color: var(--color-link);
}