A text with a dynamic size depending of the container width:

.container {
  container-type: inline-size;
}

.fluid-type {
  font-size: clamp(1rem, 4cqi, 3rem);
}

Strategy 2: Grow From a Base Font Size with calc()

font-size: calc(var(--font-size-base) + var(--font-size-fluid, 3cqi));

An upper-bound size can be set with min if needed.

Strategy 3: Generate Styles Using a Type Scale Ratio