refactor: enhance UI components and improve theme properties for better visual consistency

src/pygui/ISC/Tabs/SettingsTab.qml

@@ -107,25 +107,29 @@ Item {
             x: toggle.leftPadding
             y: parent.height / 2 - height / 2
             radius: Theme.radiusXs
-            color: toggle.checked ? Theme.primaryAccent : Theme.fieldBackground
+            color: toggle.checked ? Theme.primaryAccent : "transparent"
             border.width: Theme.borderThin
             border.color: toggle.checked ? Theme.primaryAccent : Theme.fieldBorder
 
-            Rectangle {
+            Text {
                 anchors.centerIn: parent
-                width: 9
+                text: "✓"
-                height: 9
+                font.pixelSize: 14
-                radius: Theme.radiusXs
+                font.bold: true
+                color: Theme.panelBackground
                 visible: toggle.checked
-                color: Theme.fieldBackground
+                // Small nudge to center the checkmark perfectly
+                verticalAlignment: Text.AlignVCenter
+                horizontalAlignment: Text.AlignHCenter
             }
         }
 
         contentItem: Text {
             text: toggle.text
-            color: Theme.checkboxText
+            color: Theme.headingColor
             verticalAlignment: Text.AlignVCenter
             leftPadding: toggle.indicator.width + toggle.spacing
+            font.pixelSize: 13
         }
     }
 

src/pygui/ISC/Tabs/components/ReadoutPanel.qml

@@ -9,6 +9,39 @@ ColumnLayout {
     property alias showLabels: labelsToggle.checked
     property alias heatmapBlend: heatmapSlider.value
 
+    component PanelCheckBox: CheckBox {
+        id: toggle
+        indicator: Rectangle {
+            implicitWidth: 18
+            implicitHeight: 18
+            x: toggle.leftPadding
+            y: parent.height / 2 - height / 2
+            radius: Theme.radiusXs
+            color: toggle.checked ? Theme.primaryAccent : "transparent"
+            border.width: Theme.borderThin
+            border.color: toggle.checked ? Theme.primaryAccent : Theme.fieldBorder
+
+            Text {
+                anchors.centerIn: parent
+                text: "✓"
+                font.pixelSize: 13
+                font.bold: true
+                color: Theme.panelBackground
+                visible: toggle.checked
+                verticalAlignment: Text.AlignVCenter
+                horizontalAlignment: Text.AlignHCenter
+            }
+        }
+
+        contentItem: Text {
+            text: toggle.text
+            color: Theme.headingColor
+            verticalAlignment: Text.AlignVCenter
+            leftPadding: toggle.indicator.width + toggle.spacing
+            font.pixelSize: toggle.font.pixelSize || 11
+        }
+    }
+
     // ── READOUT ───────────────────────────────────────────────────────────
     Label {
         text: "READOUT"
@@ -142,7 +175,7 @@ ColumnLayout {
         bottomPadding: 8
     }
 
-    CheckBox {
+    PanelCheckBox {
         id: labelsToggle
         text: "Labels"
         checked: true
@@ -236,7 +269,7 @@ ColumnLayout {
 
     Item { height: 10 }
 
-    CheckBox {
+    PanelCheckBox {
         id: autoCheck
         text: "Auto range  (mean ± 1σ)"
         checked: true

src/pygui/ISC/Tabs/components/SourcePanel.qml

@@ -2,6 +2,7 @@ import QtQuick
 import QtQuick.Controls
 import QtQuick.Layouts
 import ISC
+import ".."
 
 ColumnLayout {
     spacing: 6
@@ -23,6 +24,32 @@ ColumnLayout {
             Layout.alignment: Qt.AlignVCenter
         }
 
+        Button {
+            id: editBtn
+            text: "✎"
+            implicitWidth: 26
+            implicitHeight: 26
+            hoverEnabled: true
+            font.pixelSize: 14
+            background: Rectangle {
+                color: editBtn.pressed ? Theme.buttonPressed
+                     : editBtn.hovered ? Theme.buttonNeutralHover
+                     : "transparent"
+                radius: Theme.radiusSm
+            }
+            contentItem: Text {
+                text: parent.text
+                color: Theme.bodyColor
+                font: parent.font
+                horizontalAlignment: Text.AlignHCenter
+                verticalAlignment: Text.AlignVCenter
+            }
+            onClicked: {
+                file_browser.refreshFiles()
+                csvEditorDialog.open()
+            }
+        }
+
         Button {
             id: refreshBtn
             text: "⟳"
@@ -260,4 +287,9 @@ ColumnLayout {
         color: Theme.bodyColor
         font.pixelSize: 10
     }
+
+    SelectFileDialog {
+        id: csvEditorDialog
+        tableModel: file_browser.files
+    }
 }

src/pygui/ISC/Theme.qml

@@ -81,7 +81,7 @@ QtObject {
     // ── 8. Tabs (footer tab bar) ─────────────────────────────────────────────
     readonly property color tabBarBackground: tone200
     readonly property color tabBackground: "transparent"
-    readonly property color tabActiveBackground: "transparent"
+    readonly property color tabActiveBackground: isDarkMode ? "#333333" : "#FFFFFF"
     readonly property color tabHoverBackground: tone300
     readonly property color tabBorder: "transparent"
     readonly property color tabText: toneMute
@@ -132,7 +132,7 @@ QtObject {
     readonly property int tabBarHeight: 34
     readonly property int tabBarPadding: 6
     readonly property int tabSpacing: 2
-    readonly property int tabRadius: 2
+    readonly property int tabRadius: 8
     readonly property int tabFontSize: 12
     readonly property int tabButtonMinWidth: 80
     // Settings page layout