ui: dark is readable, and a version nobody compared is not zero

app/desktop/src/main/kotlin/io/github/cubsync/desktop/Theme.kt

@@ -58,19 +58,25 @@ data class CubColors(
 
 internal val DarkCubColors = CubColors(
     isDark = true,
-    // The phone's dark palette, value for value. The desktop had its own near-black set
-    // (#0F1116 against #141318), so the two ends looked like two products side by side —
-    // and the phone's is the one the design tokens name.
-    background = Color(0xFF141318),
-    surface = Color(0xFF141318),
-    surfaceRaised = Color(0xFF1F1F26),
-    surfaceSunken = Color(0xFF26252C),
+    // `html[data-theme="dark"]`, value for value — the desktop's own dark set, not the
+    // phone's. Taking the phone's (#141318 for both the canvas and the panels) put every
+    // card on the colour it was meant to stand on, and a window of one flat black field
+    // is what "深色模式看不清" looks like: nothing separates, so nothing reads.
+    background = Color(0xFF0F1116),
+    surface = Color(0xFF181B21),
+    surfaceRaised = Color(0xFF1E222A),
+    surfaceSunken = Color(0xFF242932),
     outline = Color(0xFF2A2F39),
-    outlineFaint = Color(0xFF232229),
-    outlineStrong = Color(0xFF3A3942),
-    text = Color(0xFFE6E1E9),
-    textDim = Color(0xFFC9C5D0),
-    textFaint = Color(0xFF8E8A97),
+    outlineFaint = Color(0xFF22262E),
+    outlineStrong = Color(0xFF343A46),
+    text = Color(0xFFE8EBF1),
+    // `--dim` is #98A1B0 and `--dim-2` is #6D7686 in the prototype. Both were raised for
+    // the dark window: at 11–12sp these two carry every explanatory line, and on a panel
+    // the prototype's own values read as grey-on-grey — the complaint that started this.
+    // The structure (canvas, panel, raised, sunken) is still the prototype's, value for
+    // value; only the two text weights moved, and `决策记录` says why.
+    textDim = Color(0xFFC2CAD8),
+    textFaint = Color(0xFF97A0AE),
     accent = Color(0xFF1E88E5),
     // `color-mix(in srgb, var(--win-accent) 14%, transparent)` — translucent on purpose,
     // so it composites over whatever it is put on exactly as the prototype's does.
@@ -81,10 +87,10 @@ internal val DarkCubColors = CubColors(
     success = Color(0xFF2E9E5B),
     conflict = Color(0xFFF0731F),
     info = Color(0xFF3B82F6),
-    rail = Color(0xFF1F1F26),
-    hover = Color(0xFF26252C),
-    selected = Color(0x2E4C6EF5),
-    selectedLine = Color(0xFF4C6EF5),
+    rail = Color(0xFF181B21),
+    hover = Color(0xFF232833),
+    selected = Color(0xFF1D2C3E),
+    selectedLine = Color(0xFF2B5F8F),
 )
 
 internal val LightCubColors = CubColors(

app/desktop/src/main/kotlin/io/github/cubsync/desktop/ui/Components.kt

@@ -278,7 +278,7 @@ fun SettingRow(
     ) {
         Column(Modifier.weight(1f)) {
             Text(label, style = CubType.label, color = colors.text)
-            if (hint.isNotEmpty()) Text(hint, style = CubType.meta, color = colors.textFaint)
+            if (hint.isNotEmpty()) Text(hint, style = CubType.meta, color = colors.textDim)
         }
         control()
     }
@@ -312,7 +312,7 @@ fun Toggle(checked: Boolean, enabled: Boolean = true, onChange: (Boolean) -> Uni
 fun KeyValueRow(key: String, value: String, dim: Boolean = false) {
     val colors = CubTheme.colors
     Row(Modifier.fillMaxWidth().padding(vertical = 2.dp), verticalAlignment = Alignment.Top) {
-        Text(key, style = CubType.meta, color = colors.textFaint, modifier = Modifier.width(96.dp))
+        Text(key, style = CubType.meta, color = colors.textDim, modifier = Modifier.width(96.dp))
         Text(
             value.ifEmpty { "—" },
             style = CubType.body,
@@ -459,7 +459,7 @@ fun EmptyState(text: String, detail: String = "", action: (@Composable () -> Uni
         Text(text, style = CubType.body, color = colors.textDim)
         if (detail.isNotEmpty()) {
             Spacer(Modifier.height(4.dp))
-            Text(detail, style = CubType.meta, color = colors.textFaint)
+            Text(detail, style = CubType.meta, color = colors.textDim)
         }
         if (action != null) {
             Spacer(Modifier.height(10.dp))

app/desktop/src/main/kotlin/io/github/cubsync/desktop/ui/ConnectScreen.kt

@@ -251,7 +251,10 @@ private fun NegotiationCard(state: AppState, modifier: Modifier) {
 
         Spacer(Modifier.height(14.dp))
         Kv("本机版本 / 远端版本") {
-            "${BuildInfo.PROTOCOL_VERSION * 100} / ${(peer?.protocolVersion ?: 0) * 100}"
+            // No peer is not version zero: an em dash says "nothing to compare with",
+            // where 0 read as a build from before the protocol existed.
+            val remote = peer?.protocolVersion?.let { "${it * 100}" } ?: DASH
+            "${BuildInfo.PROTOCOL_VERSION * 100} / $remote"
         }
         Kv("比对到的能力位") { "$agreed / $total" }
         Kv("v3 老版本远端") { "仅退出双向模式（清晰提示，不错位）" }

app/desktop/src/test/kotlin/io/github/cubsync/desktop/Preview.kt

@@ -128,6 +128,12 @@ object Preview {
         view: DisplayMode? = null,
         displayMenu: Boolean = false,
     ): AppState {
+        // Each state starts from the same tree: the scratch area is emptied here rather
+        // than once per JVM, so a screen cannot be photographed with whatever the test
+        // before it happened to leave behind.
+        runCatching { scratch.toFile().deleteRecursively() }
+        Files.createDirectories(scratch)
+
         val directory = Files.createTempDirectory("cubsync-preview-")
         val log = AppLog(now = { NOW })
         val desktop = DesktopSettings.inStateDirectory(directory)