diff --git a/src/Value/CalcFunction.php b/src/Value/CalcFunction.php
index c8791d98..3be53277 100644
--- a/src/Value/CalcFunction.php
+++ b/src/Value/CalcFunction.php
@@ -71,10 +71,10 @@ public static function parse(ParserState $oParserState, $bIgnoreCase = false)
             } else {
                 if (in_array($oParserState->peek(), $aOperators)) {
                     if (($oParserState->comes('-') || $oParserState->comes('+'))) {
+                        $sNextChar = $oParserState->peek(1, 1);
                         if (
                             $oParserState->peek(1, -1) != ' '
-                            || !($oParserState->comes('- ')
-                                || $oParserState->comes('+ '))
+                            || !($sNextChar === ' ' || $sNextChar === "\n" || $sNextChar === "\r")
                         ) {
                             throw new UnexpectedTokenException(
                                 " {$oParserState->peek()} ",
diff --git a/tests/ParserTest.php b/tests/ParserTest.php
index e291efd6..9446c3d9 100644
--- a/tests/ParserTest.php
+++ b/tests/ParserTest.php
@@ -1265,4 +1265,16 @@ public function escapedSpecialCaseTokens()
         self::assertTrue(is_a($urlRule->getValue(), '\Sabberworm\CSS\Value\URL'));
         self::assertTrue(is_a($calcRule->getValue(), '\Sabberworm\CSS\Value\CalcFunction'));
     }
+
+    /**
+     * @test
+     */
+    public function multilineCalc()
+    {
+        $oDoc = self::parsedStructureForFile('multiline-calc');
+        $sExpected = <<<EXPECTED
+.btn {--foo: calc(var(--bar) + ( var(--baz) + var(--qux) ) * 2);}
+EXPECTED;
+        self::assertSame($sExpected, $oDoc->render());
+    }
 }
diff --git a/tests/fixtures/multiline-calc.css b/tests/fixtures/multiline-calc.css
new file mode 100644
index 00000000..069caccf
--- /dev/null
+++ b/tests/fixtures/multiline-calc.css
@@ -0,0 +1,6 @@
+.btn {
+  --foo: calc(
+    var(--bar) +
+      (var(--baz) + var(--qux)) * 2
+  );
+}