How can I reference `@theme` values without using variables, by reusing the value statically?

If I reference variables in CSS in a nested way using the var() CSS function, it cannot properly track changes to the original variable. Is there a way in TailwindCSS to reference a value declared in @theme without using var(), so that the value is statically written into the desired place without relying on a variable?

<script src="https://cdn.jsdelivr.net/npm/@tailwindcss/browser@4"></script>
<style type="text/tailwindcss">
@theme inline {
  --color-clifford: #da373d;
}

@layer components {
  .example {
    margin: --spacing(4);
    width: --spacing(64);
    height: --spacing(16);
    background-color: var(--color-clifford);
  }
}
</style>

<div class="example">Hello World by Component</div>
<div class="m-4 w-64 h-16 bg-clifford">Hello World by Utilities</div>

Generated CSS (check yourself: Playground)

In the case of a component, the background-color is not a hardcoded static value but a variable:

.example {
  background-color: var(--color-clifford);
}

Whereas in the case of the bg-clifford utility, the hardcoded value is used as clarified in the question:

.bg-clifford {
  background-color: #da373d;
}

I would like my component to also use the hardcoded value, and the expected generated CSS should look like this:

.example {
  background-color: #da373d; /* instead of var(--color-clifford) */
}

.bg-clifford {
  background-color: #da373d;
}

Solution

If you want to use hardcoded CSS instead of a variable in a given place, use TailwindCSS's built-in theme() CSS function for that:

<script src="https://cdn.jsdelivr.net/npm/@tailwindcss/browser@4"></script>
<style type="text/tailwindcss">
@theme inline {
  --color-clifford: #da373d;
}

@layer components {
  .example {
    margin: --spacing(4);
    width: --spacing(64);
    height: --spacing(16);
    background-color: theme(--color-clifford); /* instead of var(--color-clifford) */
  }
}
</style>

<div class="example">Hello World by Component</div>
<div class="m-4 w-64 h-16 bg-clifford">Hello World by Utilities</div>

Generated CSS (check yourself: Playground)

.example {
  background-color: #da373d; /* what expected */
}

.bg-clifford {
  background-color: #da373d;
}

Important: However, keep in mind that unlike var(), theme() can only be used statically. This means that at build time, Tailwind detects theme(--color-clifford) in the source file and replaces it with the corresponding color code in the generated CSS, but afterwards it in no way behaves like var().