diff --git a/src/ui/material/draw_helpers.h b/src/ui/material/draw_helpers.h
index d323d1e..dfabaaa 100644
--- a/src/ui/material/draw_helpers.h
+++ b/src/ui/material/draw_helpers.h
@@ -35,6 +35,15 @@ inline ImU32 ScaleAlpha(ImU32 col, float scale) {
     return (col & ~IM_COL32_A_MASK) | (static_cast<ImU32>(a) << IM_COL32_A_SHIFT);
 }
 
+// True when the active theme is light (app background luminance is high).
+inline bool IsLightTheme() {
+    ImU32 bg = Background();
+    float r = ((bg >> IM_COL32_R_SHIFT) & 0xFF) / 255.0f;
+    float g = ((bg >> IM_COL32_G_SHIFT) & 0xFF) / 255.0f;
+    float b = ((bg >> IM_COL32_B_SHIFT) & 0xFF) / 255.0f;
+    return (0.299f * r + 0.587f * g + 0.114f * b) > 0.5f;
+}
+
 // Animated "loading" ellipsis: "", ".", "..", "..." cycling on a ~3Hz phase.
 inline const char* LoadingDots() {
     int n = ((int)(ImGui::GetTime() * 3.0f)) % 4;
@@ -227,6 +236,14 @@ inline void DrawButtonGlassOverlay(ImDrawList* dl, const ImVec2& bMin,
                                    const ImVec2& bMax, float rounding,
                                    bool active, bool hovered)
 {
+    // Light themes: flat buttons (like the Manage-portfolio modal's plain buttons). Skip the glass
+    // sheen + tactile 3D — ImGui::Button already draws the fill/hover/active — and add just a subtle
+    // defining edge, which reads cleaner on light surfaces than the raised glass look.
+    if (IsLightTheme()) {
+        ImU32 rim = schema::UI().resolveColor("var(--rim-light)", IM_COL32(0, 0, 0, 50));
+        dl->AddRect(bMin, bMax, active ? ScaleAlpha(rim, 0.6f) : rim, rounding, 0, 1.0f);
+        return;
+    }
     // Frosted glass highlight — subtle fill on top
     if (!active) {
         ImU32 col = hovered