theme color update

src/assets/styles/theme.css

@@ -20,6 +20,7 @@
     --m-grey15-hover: rgba(69, 87, 115, .8);
     --m-grey16: #405066;
     --m-grey16-hover: rgba(64, 80, 102, .8);
+    --m-grey17: #556772;
     --m-grey18: #1D2327;
     --m-grey19: #162534;
     --m-grey20: #1B2A38;