diff --git a/include/thirdparty/ScssPhp/ScssPhp/Compiler.php b/include/thirdparty/ScssPhp/ScssPhp/Compiler.php
index ecafc8c..86c3a8a 100644
--- a/include/thirdparty/ScssPhp/ScssPhp/Compiler.php
+++ b/include/thirdparty/ScssPhp/ScssPhp/Compiler.php
@@ -458,10 +458,33 @@ class Compiler
     }
 
     /**
-     * Compile scss
+     * Compiles the provided scss file into CSS.
+     *
+     * @param string $path
+     *
+     * @return CompilationResult
+     *
+     * @throws SassException when the source fails to compile
+     */
+    public function compileFile($path)
+    {
+        $source = file_get_contents($path);
+
+        if ($source === false) {
+            throw new \RuntimeException('Could not read the file content');
+        }
+
+        return $this->compileString($source, $path);
+    }
+
+    /**
+     * Compiles the provided scss source code into CSS.
+     *
+     * If provided, the path is considered to be the path from which the source code comes
+     * from, which will be used to resolve relative imports.
      *
      * @param string      $source
-     * @param string|null $path
+     * @param string|null $path   The path for the source, used to resolve relative imports
      *
      * @return CompilationResult
      *
@@ -1508,6 +1531,7 @@ class Compiler
         // start from the root
         while ($scope->parent && $scope->parent->type !== Type::T_ROOT) {
             array_unshift($childStash, $scope);
+            \assert($scope->parent !== null);
             $scope = $scope->parent;
         }
 
@@ -2090,6 +2114,11 @@ class Compiler
             foreach ($selector as $node) {
                 $compound = '';
 
+                if (!is_array($node)) {
+                    $output[] = $node;
+                    continue;
+                }
+
                 array_walk_recursive(
                     $node,
                     function ($value, $key) use (&$compound) {
@@ -2124,12 +2153,16 @@ class Compiler
             foreach ($selector as $node) {
                 $compound = '';
 
-                array_walk_recursive(
-                    $node,
-                    function ($value, $key) use (&$compound) {
-                        $compound .= $value;
-                    }
-                );
+                if (!is_array($node)) {
+                    $compound .= $node;
+                } else {
+                    array_walk_recursive(
+                        $node,
+                        function ($value, $key) use (&$compound) {
+                            $compound .= $value;
+                        }
+                    );
+                }
 
                 if ($this->isImmediateRelationshipCombinator($compound)) {
                     if (\count($output)) {
@@ -2885,7 +2918,7 @@ class Compiler
     {
         if (isset($child[Parser::SOURCE_LINE])) {
             $this->sourceIndex  = isset($child[Parser::SOURCE_INDEX]) ? $child[Parser::SOURCE_INDEX] : null;
-            $this->sourceLine   = isset($child[Parser::SOURCE_LINE]) ? $child[Parser::SOURCE_LINE] : -1;
+            $this->sourceLine   = $child[Parser::SOURCE_LINE];
             $this->sourceColumn = isset($child[Parser::SOURCE_COLUMN]) ? $child[Parser::SOURCE_COLUMN] : -1;
         } elseif (\is_array($child) && isset($child[1]->sourceLine) && $child[1] instanceof Block) {
             $this->sourceIndex  = $child[1]->sourceIndex;
@@ -4529,8 +4562,10 @@ EOL;
                             return $colorName;
                         }
 
-                        if (is_numeric($alpha)) {
+                        if (\is_int($alpha) || \is_float($alpha)) {
                             $a = new Number($alpha, '');
+                        } elseif (is_numeric($alpha)) {
+                            $a = new Number((float) $alpha, '');
                         } else {
                             $a = $alpha;
                         }
@@ -6984,10 +7019,14 @@ EOL;
             return static::$null;
         }
 
-        if (is_numeric($value)) {
+        if (\is_int($value) || \is_float($value)) {
             return new Number($value, '');
         }
 
+        if (is_numeric($value)) {
+            return new Number((float) $value, '');
+        }
+
         if ($value === '') {
             return static::$emptyString;
         }
diff --git a/include/thirdparty/ScssPhp/ScssPhp/LICENSE.md b/include/thirdparty/ScssPhp/ScssPhp/LICENSE.md
new file mode 100644
index 0000000..afcfdfb
--- /dev/null
+++ b/include/thirdparty/ScssPhp/ScssPhp/LICENSE.md
@@ -0,0 +1,20 @@
+Copyright (c) 2015 Leaf Corcoran, http://scssphp.github.io/scssphp
+ 
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+ 
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/include/thirdparty/ScssPhp/ScssPhp/OutputStyle.php b/include/thirdparty/ScssPhp/ScssPhp/OutputStyle.php
index c284639..a1d8b42 100644
--- a/include/thirdparty/ScssPhp/ScssPhp/OutputStyle.php
+++ b/include/thirdparty/ScssPhp/ScssPhp/OutputStyle.php
@@ -1,9 +1,62 @@
 <?php
 
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
 namespace ScssPhp\ScssPhp;
 
 final class OutputStyle
 {
     const EXPANDED = 'expanded';
     const COMPRESSED = 'compressed';
+
+    /**
+     * Converts a string to an output style.
+     *
+     * Using this method allows to write code which will support both
+     * versions 1.12+ and 2.0 of Scssphp. In 2.0, OutputStyle will be
+     * an enum instead of using string constants.
+     *
+     * @param string $string
+     *
+     * @return self::*
+     */
+    public static function fromString($string)
+    {
+        switch ($string) {
+            case 'expanded':
+                return self::EXPANDED;
+
+            case 'compressed':
+                return self::COMPRESSED;
+
+            default:
+                throw new \InvalidArgumentException('Invalid output style');
+        }
+    }
+
+    /**
+     * Converts an output style to a string supported by {@see OutputStyle::fromString()}.
+     *
+     * Using this method allows to write code which will support both
+     * versions 1.12+ and 2.0 of Scssphp. In 2.0, OutputStyle will be
+     * an enum instead of using string constants.
+     * The returned string representation is guaranteed to be compatible
+     * between 1.12 and 2.0.
+     *
+     * @param self::* $outputStyle
+     *
+     * @return string
+     */
+    public static function toString($outputStyle)
+    {
+        return $outputStyle;
+    }
 }
diff --git a/include/thirdparty/ScssPhp/ScssPhp/Parser.php b/include/thirdparty/ScssPhp/ScssPhp/Parser.php
index 1c76e7c..0debcc8 100644
--- a/include/thirdparty/ScssPhp/ScssPhp/Parser.php
+++ b/include/thirdparty/ScssPhp/ScssPhp/Parser.php
@@ -273,6 +273,11 @@ class Parser
         $this->saveEncoding();
         $this->extractLineNumbers($buffer);
 
+        if ($this->utf8 && !preg_match('//u', $buffer)) {
+            $message = $this->sourceName ? 'Invalid UTF-8 file: ' . $this->sourceName : 'Invalid UTF-8 file';
+            throw new ParserException($message);
+        }
+
         $this->pushBlock(null); // root block
         $this->whitespace();
         $this->pushBlock(null);
@@ -323,6 +328,13 @@ class Parser
 
         $list = $this->valueList($out);
 
+        if ($this->count !== \strlen($this->buffer)) {
+            $error = $this->parseError('Expected end of value');
+            $message = 'Passing trailing content after the expression when parsing a value is deprecated since Scssphp 1.12.0 and will be an error in 2.0. ' . $error->getMessage();
+
+            @trigger_error($message, E_USER_DEPRECATED);
+        }
+
         $this->restoreEncoding();
 
         return $list;
@@ -1678,9 +1690,9 @@ class Parser
      */
     protected function appendComment($comment)
     {
-        assert($this->env !== null);
-
         if (! $this->discardComments) {
+            assert($this->env !== null);
+
             $this->env->comments[] = $comment;
         }
     }
diff --git a/include/thirdparty/ScssPhp/ScssPhp/README.md b/include/thirdparty/ScssPhp/ScssPhp/README.md
new file mode 100644
index 0000000..65bb93e
--- /dev/null
+++ b/include/thirdparty/ScssPhp/ScssPhp/README.md
@@ -0,0 +1,71 @@
+# scssphp
+### <https://scssphp.github.io/scssphp>
+
+![Build](https://github.com/scssphp/scssphp/workflows/CI/badge.svg)
+[![License](https://poser.pugx.org/scssphp/scssphp/license)](https://packagist.org/packages/scssphp/scssphp)
+
+`scssphp` is a compiler for SCSS written in PHP.
+
+Checkout the homepage, <https://scssphp.github.io/scssphp>, for directions on how to use.
+
+## Running Tests
+
+`scssphp` uses [PHPUnit](https://github.com/sebastianbergmann/phpunit) for testing.
+
+Run the following command from the root directory to run every test:
+
+    vendor/bin/phpunit tests
+
+There are several tests in the `tests/` directory:
+
+* `ApiTest.php` contains various unit tests that test the PHP interface.
+* `ExceptionTest.php` contains unit tests that test for exceptions thrown by the parser and compiler.
+* `FailingTest.php` contains tests reported in Github issues that demonstrate compatibility bugs.
+* `InputTest.php` compiles every `.scss` file in the `tests/inputs` directory
+  then compares to the respective `.css` file in the `tests/outputs` directory.
+* `SassSpecTest.php` extracts tests from the `sass/sass-spec` repository.
+
+When changing any of the tests in `tests/inputs`, the tests will most likely
+fail because the output has changed. Once you verify that the output is correct
+you can run the following command to rebuild all the tests:
+
+    BUILD=1 vendor/bin/phpunit tests
+
+This will compile all the tests, and save results into `tests/outputs`. It also
+updates the list of excluded specs from sass-spec.
+
+To enable the full `sass-spec` compatibility tests:
+
+    TEST_SASS_SPEC=1 vendor/bin/phpunit tests
+
+## Coding Standard
+
+`scssphp` source conforms to [PSR12](https://www.php-fig.org/psr/psr-12/).
+
+Run the following command from the root directory to check the code for "sniffs".
+
+    vendor/bin/phpcs --standard=PSR12 --extensions=php bin src tests *.php
+
+## Static Analysis
+
+`scssphp` uses [phpstan](https://phpstan.org/) for static analysis.
+
+Run the following command from the root directory to analyse the codebase:
+
+    make phpstan
+
+As most of the codebase is composed of legacy code which cannot be type-checked
+fully, the setup contains a baseline file with all errors we want to ignore. In
+particular, we ignore all errors related to not specifying the types inside arrays
+when these arrays correspond to the representation of Sass values and Sass AST nodes
+in the parser and compiler.
+When contributing, the proper process to deal with static analysis is the following:
+
+1. Make your change in the codebase
+2. Run `make phpstan`
+3. Fix errors reported by phpstan when possible
+4. Repeat step 2 and 3 until nothing gets fixed anymore at step 3
+5. Run `make phpstan-baseline` to regenerate the phpstan baseline
+
+Additions to the baseline will be reviewed to avoid ignoring errors that should have
+been fixed.
diff --git a/include/thirdparty/ScssPhp/ScssPhp/Version.php b/include/thirdparty/ScssPhp/ScssPhp/Version.php
index d604a50..17394ce 100644
--- a/include/thirdparty/ScssPhp/ScssPhp/Version.php
+++ b/include/thirdparty/ScssPhp/ScssPhp/Version.php
@@ -19,5 +19,5 @@ namespace ScssPhp\ScssPhp;
  */
 class Version
 {
-    const VERSION = '1.11.0';
+    const VERSION = '1.12.0';
 }