diff --git a/internal/web/static/app.css b/internal/web/static/app.css
index b158596..35c2875 100644
--- a/internal/web/static/app.css
+++ b/internal/web/static/app.css
@@ -824,3 +824,10 @@ button[type="submit"]:focus-visible,
 .created-banner { display: block; }
 /* #167: gutter rows for wrapped paste view — one row per visual code line */
 .gutline { display: block; }
+/* #167: blank gutter rows must be exactly one code line tall so numbers sit
+   on each wrapped line's first row. Desktop uses the code font vars; the
+   mobile media query overrides .code font-size to 13px, mirrored here. */
+.code .gutter .gutline { height: calc(var(--code-fs) * var(--code-lh)); }
+@media (max-width: 640px) {
+  .code .gutter .gutline { height: calc(13px * 1.7); }
+}