diff --git a/HellionChat/Ui/StyleEngine/BaselineMath.cs b/HellionChat/Ui/StyleEngine/BaselineMath.cs
new file mode 100644
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+++ b/HellionChat/Ui/StyleEngine/BaselineMath.cs
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+namespace HellionChat.Ui.StyleEngine;
+
+// TEST-MIRROR: Ui/BaselineMathTests.cs
+//
+// ImGui lines items up on a row by their top edge, not their baseline: ItemSize
+// only shifts anything when CurrLineTextBaseOffset is non-zero, and that stays at
+// zero unless AlignTextToFramePadding ran. So a smaller face beside a larger one
+// hangs, flush at the top and floating above the baseline.
+//
+// The correction is the difference between the two ascents. It is easy to assume
+// the display scale is applied twice here and it is not: Dalamud rasterises at
+// SizePx * GlobalScale and then divides the metrics straight back down
+// (ImGuiHelpers.AdjustGlyphMetrics(1 / scale, ...)), so ImFont.Ascent is a
+// logical value. Drawing multiplies it up again -- and so must this.
+internal static class BaselineMath
+{
+    internal static float OffsetFor(float ascentLarge, float ascentSmall, float uiScale) =>
+        MathF.Max(0f, (ascentLarge - ascentSmall) * uiScale);
+}