diff --git a/src/renderer/text.c b/src/renderer/text.c
index 8ace20a..11d936b 100644
--- a/src/renderer/text.c
+++ b/src/renderer/text.c
@@ -112,6 +112,29 @@ static void clean_cairo_context(cairo_t *cr) {
   cairo_restore(cr);
 }
 
+static void draw_rect(cairo_t *cr, int32_t x, int32_t y, uint32_t width,
+                      uint32_t height, bool fill, color_t *color,
+                      uint32_t line_width) {
+  cairo_set_line_width(cr, line_width);
+  if (fill) {
+    cairo_rectangle(cr, x, y, width, height);
+    cairo_set_source_rgba(cr, color->red, color->green, color->blue,
+                          color->alpha);
+    cairo_fill(cr);
+  } else {
+    double half_lw = (double)line_width / 2;
+    double sx = x, sy = y, w = width, h = height;
+    sx += half_lw;
+    sy += half_lw;
+    w -= line_width;
+    h -= line_width;
+    cairo_rectangle(cr, sx, sy, w, h);
+    cairo_set_source_rgba(cr, color->red, color->green, color->blue,
+                          color->alpha);
+    cairo_stroke(cr);
+  }
+}
+
 void draw_bar(monitor_t *monitor, bool is_current_monitor,
               color_set_t *color_set, uint32_t height, uint32_t tag_x_padding) {
   cairo_t *cr = monitor->cr;
@@ -119,13 +142,18 @@ void draw_bar(monitor_t *monitor, bool is_current_monitor,
   uint32_t width = 0;
   const char *text;
   color_t *color;
+  uint32_t tag_mask_has_client = 0;
+  for (client_t *c = monitor->clients; c; c = c->next) {
+    tag_mask_has_client |= c->tags;
+  }
 
   clean_cairo_context(cr);
   draw_background(cr, &color_set->bar_bg, 0, 0, monitor->monitor_width, height);
 
   /* 绘制 tags */
-  for (int i = 0; i < g_strv_length(monitor->tags); i++) {
+  for (uint32_t i = 0; i < g_strv_length(monitor->tags); i++) {
     bool selected = (monitor->selected_tags >> i) & 0x1;
+    bool has_client = (1 << i) & tag_mask_has_client;
     text = monitor->tags[i];
     width = get_text_width(text) + tag_x_padding * 2;
 
@@ -134,6 +162,7 @@ void draw_bar(monitor_t *monitor, bool is_current_monitor,
       draw_background(cr, color, x, 0, width, height);
     }
     color = selected ? &color_set->active_tag_color : &color_set->tag_color;
+    if (has_client) draw_rect(cr, x, 0, 4, 4, selected, color, 1);
     draw_text(cr, text, color, x, 0, width, height, true);
     x += width;
   }