The SDL_Delay call was moved to the top of the loop so that it occurs
even while paused.
---
 include/state.h |  1 +
 src/main.c      | 30 +++++++++++++++++++++++++-----
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/include/state.h b/include/state.h
index 6d142dd..4f9f5ec 100644
--- a/include/state.h
+++ b/include/state.h
@@ -13,6 +13,7 @@ enum block_state {
 
 struct state {
 	bool running;
+	bool paused;
 	SDL_Renderer *renderer;
 
 	int hearts;
diff --git a/src/main.c b/src/main.c
index 8340ef0..81cea48 100644
--- a/src/main.c
+++ b/src/main.c
@@ -26,6 +26,7 @@ main()
 
 	struct state st = {
 		.running = true,
+		.paused = false,
 		.renderer = SDL_CreateRenderer(win, -1, 0),
 		.hearts = 5,
 		.score = 0,
@@ -56,23 +57,43 @@ main()
 
 	while (st.running) {
 		SDL_Event event;
+		SDL_Delay(1000 / 60);
 		while (SDL_PollEvent(&event)) {
+			/* Exiting and pausing/unpausing need to occur whether
+			 * or not the game is paused.
+			 */
 			switch (event.type) {
-			case SDL_MOUSEMOTION:
-				paddle_move(&st.paddle, event.motion.x);
-				break;
 			case SDL_KEYUP:
 				switch (event.key.keysym.sym) {
 				case SDLK_q:
-				case SDLK_ESCAPE:
 					st.running = false;
 					break;
+				case SDLK_ESCAPE:
+					st.paused = !st.paused;
+					break;
 				}
 				break;
 			case SDL_QUIT:
 				st.running = false;
 				break;
 			}
+
+			if (st.paused || !st.running) {
+				break;
+			}
+
+			switch (event.type) {
+			case SDL_MOUSEMOTION:
+				paddle_move(&st.paddle, event.motion.x);
+				break;
+			}
+		}
+
+		if (st.paused) {
+			continue;
+		}
+		if (!st.running) {
+			break;
 		}
 
 		ball_update(&st);
@@ -119,7 +140,6 @@ main()
 		}
 
 		SDL_RenderPresent(st.renderer);
-		SDL_Delay(1000 / 60);
 	}
 
 	for (size_t row = 0; row < 10; row++) {
-- 
2.34.1

Thanks, applied!

I also added a little visual effect when the game is paused.

To git.sr.ht:~yerinalexey/sdl2-breakout
   029cc14..107d442  master -> master