fix(ui): remap dark article colors in dark theme

Colors set by dictionaries such as navy, dark red and brown are nearly invisible on the dark background. Swap the dark named colors for lighter tones when rendering in the dark theme; the light theme keeps the original colors.

app/src/main/java/com/example/research/ui/article/ArticleScreen.kt

@@ -11,6 +11,7 @@ import androidx.compose.runtime.*
 import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.luminance
 import androidx.compose.ui.layout.onSizeChanged
 import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.platform.testTag
@@ -197,12 +198,22 @@ fun ArticleContent(
                 articleState.dslContent.size > HEAVY_ARTICLE_BLOCK_COUNT
 
             val density = LocalDensity.current
+            val darkTheme = MaterialTheme.colorScheme.background.luminance() < 0.5f
             val displayBlocks = remember(
                 articleState.dslContent,
                 density,
-                baseTextStyle
+                baseTextStyle,
+                darkTheme
             ) {
-                mergeDslBlocks(articleState.dslContent, density, baseTextStyle)
+                val merged =
+                    mergeDslBlocks(articleState.dslContent, density, baseTextStyle)
+                if (darkTheme) {
+                    merged.map {
+                        it.copy(text = DslAnnotatedParser.remapForDarkTheme(it.text))
+                    }
+                } else {
+                    merged
+                }
             }
             val articleList: @Composable (Modifier) -> Unit = { listModifier ->
                 LazyColumn(

app/src/main/java/com/example/research/ui/article/DslAnnotatedParser.kt

@@ -411,6 +411,35 @@ object DslAnnotatedParser {
         linkText = Color(0xFF1E88E5),
     )
 
+    private val DARK_THEME_COLORS: Map<Color, Color> = mapOf(
+        Color(0xFF000000) to Color(0xFFE8E6E3),
+        Color(0xFF000080) to Color(0xFF8FA8E0),
+        Color(0xFF00008B) to Color(0xFF8FA8E0),
+        Color(0xFF0000FF) to Color(0xFF7C9CE8),
+        Color(0xFF006400) to Color(0xFF66BB6A),
+        Color(0xFF008000) to Color(0xFF66BB6A),
+        Color(0xFF8B0000) to Color(0xFFE57373),
+        Color(0xFF800000) to Color(0xFFE57373),
+        Color(0xFF800080) to Color(0xFFBA68C8),
+        Color(0xFFA52A2A) to Color(0xFFBCAAA4),
+        Color(0xFF008080) to Color(0xFF4DB6AC),
+        Color(0xFF808000) to Color(0xFFC0CA33),
+    )
+
+    fun remapForDarkTheme(text: AnnotatedString): AnnotatedString {
+        if (text.spanStyles.none { it.item.color in DARK_THEME_COLORS }) return text
+        val builder = AnnotatedString.Builder(text.text)
+        text.spanStyles.forEach { range ->
+            val style = DARK_THEME_COLORS[range.item.color]
+                ?.let { range.item.copy(color = it) } ?: range.item
+            builder.addStyle(style, range.start, range.end)
+        }
+        text.paragraphStyles.forEach { range ->
+            builder.addStyle(range.item, range.start, range.end)
+        }
+        return builder.toAnnotatedString()
+    }
+
     // Allow external cache clearing (e.g., when dictionaries change)
     fun clearRefCache() {
         refCache.evictAll()