round1, background 2, ..., backgroundN;
}
            </code></pre>
          </section>

          <section>
            <img style="max-width: 33%" src="/images/slides/lightmap-layered1.png" />
            <img style="max-width: 33%" src="/images/slides/lightmap-layered2.png" />
            <img style="max-width: 33%" src="/images/slides/lightmap-layered3.png" />
          </section>

          <section>
            <pre><code>
$shadow: rgba(0, 0, 0, 0.25);

.bottom {
  ...
  &.shade {
    &.full {
      