SVG Relative Path

HTML

<svg width='570' height='270'>
    <!-- relative -->
    <path d='m30 10, 0 30, -30 0' />
    <path d='m300 10, 0 30, 30 0' />
    <path d='m0 200, 30 0, 0 30' />
    <path d='m300 230, 0 -30, 30 0' />
</svg>

CSS

html, body {
    background: #222;
}
svg {
    background: yellow;
}
path {
    stroke: red;
    fill: none;
}