how to vertical align only the heading h1 to top.

[cmaspi]

I want to align only the heading to the top but not any other content in the slide.

After hours of googling, I found only the following solution

style: |
  section {
    justify-content: start;    
  }

However, this aligns everything. Being a novice in CSS, my natural instinct was to use h1 instead of section. That doesn't appear to solve anything though.

[yhatt]

A simple solution is using absolutely positioning to h1.

style: |
  h1 {
    position: absolute;
    top: 60px;
    left: 75px;
    right: 75px;
  }

Suitable distances for top, left, and right may be different by using theme.

Another solution

The positioning of absolute element is not affected from other elements, so may overlap with slide contents if there are a lot of contents.

For centering in cross axis (vertically in this case) with keeping flex items, sandwich main contents with 2 flex items that has flex-grow: 1. Following style is using h1 and a generated empty content to sandwich.

section > h1 {
  flex: 1 0 auto;
  padding: 0;
  margin: 0;
  order: -999999;
}

section:has(> h1)::before {
  flex: 1 0 auto;
  display: block;
  content: '';
  order: 999999;
}