Just add theme info to root style.css, compile everything to styles.min.css

assets/css/styles.min.css

@@ -0,0 +1 @@
+@font-face{font-display:swap;font-family:Zx Spectrum;font-style:normal;font-weight:100;font-weight:400;src:url(/wp-content/themes/zx-spectrum/assets/fonts/zx_spectrum-7-webfont.woff2) format("woff2"),url(/wp-content/themes/zx-spectrum/assets/fonts/zx_spectrum-7-webfont.woff) format("woff")}@font-face{font-display:swap;font-family:Zx Spectrum;font-style:bold;font-weight:700;src:url(/wp-content/themes/zx-spectrum/assets/fonts/zx_spectrum-7_bold-webfont.woff2) format("woff2"),url(/wp-content/themes/zx-spectrum/assets/fonts/zx_spectrum-7_bold-webfont.woff) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:100;src:url(/fonts/inter/Inter-Thin.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Thin.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:100;src:url(/fonts/inter/Inter-ThinItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ThinItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:200;src:url(/fonts/inter/Inter-ExtraLight.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ExtraLight.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:200;src:url(/fonts/inter/Inter-ExtraLightItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ExtraLightItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:300;src:url(/fonts/inter/Inter-Light.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Light.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:300;src:url(/fonts/inter/Inter-LightItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-LightItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:400;src:url(/fonts/inter/Inter-Regular.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Regular.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:400;src:url(/fonts/inter/Inter-Italic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Italic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:500;src:url(/fonts/inter/Inter-Medium.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Medium.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:500;src:url(/fonts/inter/Inter-MediumItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-MediumItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:600;src:url(/fonts/inter/Inter-SemiBold.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-SemiBold.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:600;src:url(/fonts/inter/Inter-SemiBoldItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-SemiBoldItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:700;src:url(/fonts/inter/Inter-Bold.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Bold.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:700;src:url(/fonts/inter/Inter-BoldItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-BoldItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:800;src:url(/fonts/inter/Inter-ExtraBold.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ExtraBold.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:800;src:url(/fonts/inter/Inter-ExtraBoldItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ExtraBoldItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:900;src:url(/fonts/inter/Inter-Black.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Black.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:900;src:url(/fonts/inter/Inter-BlackItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-BlackItalic.woff?v=3.19) format("woff")}@font-face{font-named-instance:"Regular";font-display:swap;font-family:Inter var;font-style:normal;font-weight:100 900;src:url(/fonts/inter/Inter-roman.var.woff2?v=3.19) format("woff2")}@font-face{font-named-instance:"Italic";font-display:swap;font-family:Inter var;font-style:italic;font-weight:100 900;src:url(/fonts/inter/Inter-italic.var.woff2?v=3.19) format("woff2")}@font-face{font-display:swap;font-family:Inter var experimental;font-style:oblique 0deg 10deg;font-weight:100 900;src:url(/fonts/inter/Inter.var.woff2?v=3.19) format("woff2")}@font-face{font-display:swap;font-family:Christmas;font-style:normal;src:url(/fonts/christmas.ttf) format("ttf")}:Line truncated

functions.php

@@ -3,7 +3,7 @@
 add_theme_support( 'title-tag' );
 
 function zxs_add_themes() {
-	wp_enqueue_style('zxs_globals', get_stylesheet_directory_uri() . "/style.css",  array(), wp_get_theme()->get( 'Version' ), 'all');
+	wp_enqueue_style('zxs_globals', get_stylesheet_directory_uri() . "/assets/css/styles.min.css",  array(), wp_get_theme()->get( 'Version' ), 'all');
 }
 
 

package.json

@@ -5,7 +5,7 @@
   "main": "index.js",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1",
-    "build:css": "postcss assets/css/styles.css > style.css"
+    "build:css": "postcss assets/css/styles.css > assets/css/styles.min.css"
   },
   "repository": {
     "type": "git",

style.css

@@ -1 +1,17 @@
-@font-face{font-display:swap;font-family:Zx Spectrum;font-style:normal;font-weight:100;font-weight:400;src:url(/wp-content/themes/zx-spectrum/assets/fonts/zx_spectrum-7-webfont.woff2) format("woff2"),url(/wp-content/themes/zx-spectrum/assets/fonts/zx_spectrum-7-webfont.woff) format("woff")}@font-face{font-display:swap;font-family:Zx Spectrum;font-style:bold;font-weight:700;src:url(/wp-content/themes/zx-spectrum/assets/fonts/zx_spectrum-7_bold-webfont.woff2) format("woff2"),url(/wp-content/themes/zx-spectrum/assets/fonts/zx_spectrum-7_bold-webfont.woff) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:100;src:url(/fonts/inter/Inter-Thin.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Thin.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:100;src:url(/fonts/inter/Inter-ThinItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ThinItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:200;src:url(/fonts/inter/Inter-ExtraLight.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ExtraLight.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:200;src:url(/fonts/inter/Inter-ExtraLightItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ExtraLightItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:300;src:url(/fonts/inter/Inter-Light.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Light.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:300;src:url(/fonts/inter/Inter-LightItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-LightItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:400;src:url(/fonts/inter/Inter-Regular.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Regular.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:400;src:url(/fonts/inter/Inter-Italic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Italic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:500;src:url(/fonts/inter/Inter-Medium.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Medium.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:500;src:url(/fonts/inter/Inter-MediumItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-MediumItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:600;src:url(/fonts/inter/Inter-SemiBold.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-SemiBold.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:600;src:url(/fonts/inter/Inter-SemiBoldItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-SemiBoldItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:700;src:url(/fonts/inter/Inter-Bold.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Bold.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:700;src:url(/fonts/inter/Inter-BoldItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-BoldItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:800;src:url(/fonts/inter/Inter-ExtraBold.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ExtraBold.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:800;src:url(/fonts/inter/Inter-ExtraBoldItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-ExtraBoldItalic.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:normal;font-weight:900;src:url(/fonts/inter/Inter-Black.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-Black.woff?v=3.19) format("woff")}@font-face{font-display:swap;font-family:Inter;font-style:italic;font-weight:900;src:url(/fonts/inter/Inter-BlackItalic.woff2?v=3.19) format("woff2"),url(/fonts/inter/Inter-BlackItalic.woff?v=3.19) format("woff")}@font-face{font-named-instance:"Regular";font-display:swap;font-family:Inter var;font-style:normal;font-weight:100 900;src:url(/fonts/inter/Inter-roman.var.woff2?v=3.19) format("woff2")}@font-face{font-named-instance:"Italic";font-display:swap;font-family:Inter var;font-style:italic;font-weight:100 900;src:url(/fonts/inter/Inter-italic.var.woff2?v=3.19) format("woff2")}@font-face{font-display:swap;font-family:Inter var experimental;font-style:oblique 0deg 10deg;font-weight:100 900;src:url(/fonts/inter/Inter.var.woff2?v=3.19) format("woff2")}@font-face{font-display:swap;font-family:Christmas;font-style:normal;src:url(/fonts/christmas.ttf) format("ttf")}:Line truncated
+@charset "UTF-8";
+
+/*
+Theme Name: ZX Spectrum
+Theme URI: https://lewisdale.dev
+Author: Lewis Dale
+Author URI: https://lewisdale.dev/
+Description: A blast from the past
+Requires at least: 5.3
+Tested up to: 6.1
+Requires PHP: 5.6
+Version: 1.7
+License: GNU General Public License v2 or later
+License URI: http://www.gnu.org/licenses/gpl-2.0.html
+Text Domain: zxs
+Tags: one-column, accessibility-ready, custom-colors, custom-menu, custom-logo, editor-style, featured-images, footer-widgets, block-patterns, rtl-language-support, sticky-post, threaded-comments, translation-ready.
+*/