diff --git a/src/Value/CSSFunction.php b/src/Value/CSSFunction.php
index 300dc3ec..570dc0fc 100644
--- a/src/Value/CSSFunction.php
+++ b/src/Value/CSSFunction.php
@@ -33,6 +33,35 @@ public function __construct($sName, $aArguments, $sSeparator = ',', $iLineNo = 0
         parent::__construct($aArguments, $sSeparator, $iLineNo);
     }
 
+    /**
+     * @param ParserState $oParserState
+     * @param bool $bIgnoreCase
+     *
+     * @return string
+     *
+     * @throws SourceException
+     * @throws UnexpectedEOFException
+     * @throws UnexpectedTokenException
+     */
+    public static function parseName(ParserState $oParserState, $bIgnoreCase = false)
+    {
+        return $oParserState->parseIdentifier($bIgnoreCase);
+    }
+
+    /**
+     * @param ParserState $oParserState
+     *
+     * @return array
+     *
+     * @throws SourceException
+     * @throws UnexpectedEOFException
+     * @throws UnexpectedTokenException
+     */
+    public static function parseArgs(ParserState $oParserState)
+    {
+        return Value::parseValue($oParserState, ['=', ' ', ',']);
+    }
+
     /**
      * @param ParserState $oParserState
      * @param bool $bIgnoreCase
@@ -45,9 +74,9 @@ public function __construct($sName, $aArguments, $sSeparator = ',', $iLineNo = 0
      */
     public static function parse(ParserState $oParserState, $bIgnoreCase = false)
     {
-        $mResult = $oParserState->parseIdentifier($bIgnoreCase);
+        $mResult = self::parseName($oParserState, $bIgnoreCase);
         $oParserState->consume('(');
-        $aArguments = Value::parseValue($oParserState, ['=', ' ', ',']);
+        $aArguments = self::parseArgs($oParserState);
         $mResult = new CSSFunction($mResult, $aArguments, ',', $oParserState->currentLine());
         $oParserState->consume(')');
         return $mResult;
diff --git a/src/Value/Value.php b/src/Value/Value.php
index a920396b..3cd98da1 100644
--- a/src/Value/Value.php
+++ b/src/Value/Value.php
@@ -72,6 +72,9 @@ public static function parseValue(ParserState $oParserState, array $aListDelimit
             }
             $iStartPosition = null;
             while (($iStartPosition = array_search($sDelimiter, $aStack, true)) !== false) {
+                if ($iStartPosition === 0) {
+                    break;
+                }
                 $iLength = 2; //Number of elements to be joined
                 for ($i = $iStartPosition + 2; $i < count($aStack); $i += 2, ++$iLength) {
                     if ($sDelimiter !== $aStack[$i]) {
@@ -156,7 +159,16 @@ public static function parsePrimitiveValue(ParserState $oParserState)
         } elseif ($oParserState->comes("U+")) {
             $oValue = self::parseUnicodeRangeValue($oParserState);
         } else {
-            $oValue = self::parseIdentifierOrFunction($oParserState);
+            $sNextChar = $oParserState->peek(1);
+            try {
+                $oValue = self::parseIdentifierOrFunction($oParserState);
+            } catch (UnexpectedTokenException $e) {
+                if (in_array($sNextChar, ['+', '-', '*', '/'], true)) {
+                    $oValue = $oParserState->consume(1);
+                } else {
+                    throw $e;
+                }
+            }
         }
         $oParserState->consumeWhiteSpace();
         return $oValue;
diff --git a/tests/ParserTest.php b/tests/ParserTest.php
index 74449ee2..9235cb03 100644
--- a/tests/ParserTest.php
+++ b/tests/ParserTest.php
@@ -1240,6 +1240,29 @@ public function lonelyImport()
         self::assertSame($sExpected, $oDoc->render());
     }
 
+    /**
+     * @test
+     */
+    public function functionArithmeticInFile()
+    {
+        $oDoc = self::parsedStructureForFile('function-arithmetic', Settings::create()->withMultibyteSupport(true));
+        $sExpected = 'div {height: max(300,vh + 10);}
+div {height: max(300,vh - 10);}
+div {height: max(300,vh * 10);}
+div {height: max(300,vh / 10);}';
+        self::assertSame($sExpected, $oDoc->render());
+    }
+
+    /**
+     * @test
+     */
+    public function infiniteLoopInFile()
+    {
+        $oDoc = self::parsedStructureForFile('infinite-loop', Settings::create()->withMultibyteSupport(true));
+        $sExpected = 'div {}';
+        self::assertSame($sExpected, $oDoc->render());
+    }
+
     public function escapedSpecialCaseTokens()
     {
         $oDoc = $this->parsedStructureForFile('escaped-tokens');
diff --git a/tests/fixtures/function-arithmetic.css b/tests/fixtures/function-arithmetic.css
new file mode 100644
index 00000000..07a2c318
--- /dev/null
+++ b/tests/fixtures/function-arithmetic.css
@@ -0,0 +1,12 @@
+div {
+    height: max(300, vh + 10);
+}
+div {
+    height: max(300, vh - 10);
+}
+div {
+    height: max(300, vh * 10);
+}
+div {
+    height: max(300, vh / 10);
+}
diff --git a/tests/fixtures/infinite-loop.css b/tests/fixtures/infinite-loop.css
new file mode 100644
index 00000000..9f7f31d5
--- /dev/null
+++ b/tests/fixtures/infinite-loop.css
@@ -0,0 +1,3 @@
+div {
+    height: ///!;
+}