Update syntax highlighting

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/KotlinExplorer.kt

@@ -448,8 +448,8 @@ private fun RSyntaxTextArea.configureSyntaxTextArea(syntaxStyle: String, focusTr
 
 private fun applyTheme(textArea: RSyntaxTextArea) {
     try {
-        val theme = Theme.load(RSyntaxTextArea::class.java.getResourceAsStream(
-            "/org/fife/ui/rsyntaxtextarea/themes/idea.xml")
+        val theme = Theme.load(UiState::class.java.getResourceAsStream(
+            "/themes/kotlin_explorer.xml")
         )
         theme.apply(textArea)
     } catch (ioe: IOException) {

src/jvmMain/resources/themes/kotlin_explorer.xml

@@ -0,0 +1,70 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE RSyntaxTheme SYSTEM "theme.dtd">
+
+<RSyntaxTheme version="1.0">
+   <!--  General editor colors. -->
+   <background color="ffffff" />
+   <caret color="000000" />
+   <selection fg="ffffff" bg="526da5" />
+   <currentLineHighlight color="f5f8fe" fade="false" />
+   <marginLine fg="b0b4b9" />
+   <markAllHighlight color="edebfc" />
+   <markOccurrencesHighlight color="edebfc" border="false" />
+   <matchedBracket fg="93d9d9" bg="93d9d9" highlightBoth="true" animate="false" />
+   <hyperlinks fg="0000ff" />
+   <secondaryLanguages>
+      <language index="1" bg="fff0cc" />
+      <language index="2" bg="dafeda" />
+      <language index="3" bg="ffe0f0" />
+   </secondaryLanguages>
+
+   <!-- Gutter styling. -->
+   <gutterBorder color="dddddd" />
+   <lineNumbers fg="787878" />
+   <foldIndicator fg="808080" armedFg="585858" iconBg="ffffff" />
+   <iconRowHeader activeLineRange="3399ff" />
+
+   <!-- Syntax tokens. -->
+   <tokenStyles>
+      <style token="IDENTIFIER" fg="000000" />
+      <style token="RESERVED_WORD" fg="0033b3" />
+      <style token="RESERVED_WORD_2" fg="0033b3" />
+      <style token="ANNOTATION" fg="9e880d" />
+      <style token="COMMENT_DOCUMENTATION" fg="8c8c8c" italic="true" />
+      <style token="COMMENT_EOL" fg="8c8c8c" italic="true" />
+      <style token="COMMENT_MULTILINE" fg="8c8c8c" italic="true" />
+      <style token="COMMENT_KEYWORD" fg="8c8c8c" underline="true" italic="true" />
+      <style token="COMMENT_MARKUP" fg="8c8c8c" bg="e2ffe2" italic="true" />
+      <style token="DATA_TYPE" fg="871094" />
+      <style token="FUNCTION" fg="00627a" />
+      <style token="LITERAL_BOOLEAN" fg="000080" />
+      <style token="LITERAL_NUMBER_DECIMAL_INT" fg="1750eb" />
+      <style token="LITERAL_NUMBER_FLOAT" fg="1750eb" />
+      <style token="LITERAL_NUMBER_HEXADECIMAL" fg="1750eb" />
+      <style token="LITERAL_STRING_DOUBLE_QUOTE" fg="067d17" />
+      <style token="LITERAL_CHAR" fg="067d17" />
+      <style token="LITERAL_BACKQUOTE" fg="067d17" bg="ffcccc" />
+      <style token="MARKUP_TAG_DELIMITER" fg="000000" bold="true" />
+      <style token="MARKUP_TAG_NAME" fg="000080" bold="true" />
+      <style token="MARKUP_TAG_ATTRIBUTE" fg="0000ff" bold="true" />
+      <style token="MARKUP_TAG_ATTRIBUTE_VALUE" fg="008000" bold="true" />
+      <style token="MARKUP_COMMENT" fg="808080" italic="true"/>
+      <style token="MARKUP_DTD" fg="808080"/>
+      <style token="MARKUP_PROCESSING_INSTRUCTION"  fg="808080"/>
+      <style token="MARKUP_CDATA" fg="cc6600"/>
+      <style token="MARKUP_CDATA_DELIMITER" fg="008080"/>
+      <style token="MARKUP_ENTITY_REFERENCE" fg="008000"/>
+      <style token="OPERATOR" fg="000000" />
+      <style token="PREPROCESSOR" fg="808080" />
+      <style token="REGEX" fg="871094" />
+      <style token="SEPARATOR" fg="000000" />
+      <style token="VARIABLE" fg="871094" />
+      <style token="WHITESPACE" fg="000000" />
+
+      <style token="ERROR_IDENTIFIER" fg="ff0000" />
+      <style token="ERROR_NUMBER_FORMAT" fg="ff0000" />
+      <style token="ERROR_STRING_DOUBLE" fg="ff0000" />
+      <style token="ERROR_CHAR" fg="ff0000" />
+   </tokenStyles>
+
+</RSyntaxTheme>