diff --git a/composer.json b/composer.json
index a77bb4f4f..391dfe0f6 100644
--- a/composer.json
+++ b/composer.json
@@ -76,7 +76,7 @@
 		"masterminds/html5": "^2.7",
 		"tubalmartin/cssmin": "^4.1",
 		"wptt/webfont-loader": "^1.1",
-		"sabberworm/php-css-parser": "^8.4",
+		"sabberworm/php-css-parser": "^9.0",
 		"stripe/stripe-php": "^15.3",
 		"enshrined/svg-sanitize": "^0.21.0"
 	}
diff --git a/composer.lock b/composer.lock
index 7fa0b70a6..9e92b8d60 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "341c7931ffba722141772961613cf262",
+    "content-hash": "2933e226a6422304884680b53cbba8f5",
     "packages": [
         {
             "name": "codeinwp/themeisle-sdk",
@@ -161,24 +161,32 @@
         },
         {
             "name": "sabberworm/php-css-parser",
-            "version": "v8.8.0",
+            "version": "v9.0.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/MyIntervals/PHP-CSS-Parser.git",
-                "reference": "3de493bdddfd1f051249af725c7e0d2c38fed740"
+                "reference": "54574e3de2f8cdc91175ffd2337e5c6804a7d729"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/MyIntervals/PHP-CSS-Parser/zipball/3de493bdddfd1f051249af725c7e0d2c38fed740",
-                "reference": "3de493bdddfd1f051249af725c7e0d2c38fed740",
+                "url": "https://api.github.com/repos/MyIntervals/PHP-CSS-Parser/zipball/54574e3de2f8cdc91175ffd2337e5c6804a7d729",
+                "reference": "54574e3de2f8cdc91175ffd2337e5c6804a7d729",
                 "shasum": ""
             },
             "require": {
                 "ext-iconv": "*",
-                "php": "^5.6.20 || ^7.0.0 || ~8.0.0 || ~8.1.0 || ~8.2.0 || ~8.3.0 || ~8.4.0"
+                "php": "^7.2.0 || ~8.0.0 || ~8.1.0 || ~8.2.0 || ~8.3.0 || ~8.4.0"
             },
             "require-dev": {
-                "phpunit/phpunit": "5.7.27 || 6.5.14 || 7.5.20 || 8.5.41"
+                "php-parallel-lint/php-parallel-lint": "1.4.0",
+                "phpstan/extension-installer": "1.4.3",
+                "phpstan/phpstan": "1.12.28 || 2.1.19",
+                "phpstan/phpstan-phpunit": "1.4.2 || 2.0.7",
+                "phpstan/phpstan-strict-rules": "1.6.2 || 2.0.6",
+                "phpunit/phpunit": "8.5.42",
+                "rawr/phpunit-data-provider": "3.3.1",
+                "rector/rector": "1.2.10 || 2.1.2",
+                "rector/type-perfect": "1.0.0 || 2.1.0"
             },
             "suggest": {
                 "ext-mbstring": "for parsing UTF-8 CSS"
@@ -186,7 +194,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-main": "9.0.x-dev"
+                    "dev-main": "9.1.x-dev"
                 }
             },
             "autoload": {
@@ -220,9 +228,9 @@
             ],
             "support": {
                 "issues": "https://github.com/MyIntervals/PHP-CSS-Parser/issues",
-                "source": "https://github.com/MyIntervals/PHP-CSS-Parser/tree/v8.8.0"
+                "source": "https://github.com/MyIntervals/PHP-CSS-Parser/tree/v9.0.0"
             },
-            "time": "2025-03-23T17:59:05+00:00"
+            "time": "2025-07-27T07:24:01+00:00"
         },
         {
             "name": "stripe/stripe-php",