feat: help box "m" explanation

src/ui/draw_blocks.rs

@@ -634,8 +634,20 @@ pub fn draw_info<B: Backend>(f: &mut Frame<'_, B>, text: String) {
 /// draw a box in the center of the screen, based on max line width + number of lines
 fn draw_popup(text_lines: u16, text_width: u16, r: Rect, box_location: BoxLocation) -> Rect {
     // This can panic if number_lines or max_line_width is larger than r.height or r.width
-    let blank_vertical = (r.height - text_lines) / 2;
+
-    let blank_horizontal = (r.width - text_width) / 2;
+	
+
+    let blank_vertical = if r.height > text_lines {
+		(r.height - text_lines) / 2
+	} else {
+		r.height / 2
+	};
+    let blank_horizontal =  if r.width > text_width { 
+		(r.width - text_width) / 2
+	}else {
+		r.width / 2
+
+	};
 
     let vertical_constraints = box_location.get_vertical_constraints(blank_vertical, text_lines);
     let horizontal_constraints =