diff --git a/deploy/nginx/locations.conf b/deploy/nginx/locations.conf
index a9a9139..17d0018 100644
--- a/deploy/nginx/locations.conf
+++ b/deploy/nginx/locations.conf
@@ -32,7 +32,28 @@ location /.well-known {
     alias /data/ssl/.well-known;
 }
 
+# 注意：location 里一旦出现 add_header，http 级的 add_header 就不再继承，
+# 所以下面两个 block 都要把 nginx.conf 里的安全头重新写一遍。
+
+# 构建产物文件名带内容 hash，内容一变文件名就变，可以永久缓存。
+# 命中后浏览器直接读磁盘，不再发条件请求。
+location /assets/ {
+    root /app/dist;
+    expires 1y;
+    add_header Cache-Control "public, immutable";
+    add_header X-XSS-Protection "1; mode=block" always;
+    add_header X-Frame-Options SAMEORIGIN always;
+    add_header X-Content-Type-Options nosniff always;
+    access_log off;
+}
+
 location / {
     root /app/dist;
     try_files $uri $uri/ /index.html =404;
+    # index.html 引用着带 hash 的文件名，必须每次回源校验，
+    # 否则发新版后学生刷不到。no-cache 是"缓存但每次校验"，命中走 304。
+    add_header Cache-Control "no-cache";
+    add_header X-XSS-Protection "1; mode=block" always;
+    add_header X-Frame-Options SAMEORIGIN always;
+    add_header X-Content-Type-Options nosniff always;
 }
diff --git a/deploy/nginx/nginx.conf b/deploy/nginx/nginx.conf
index 4beafdc..839a585 100644
--- a/deploy/nginx/nginx.conf
+++ b/deploy/nginx/nginx.conf
@@ -19,7 +19,18 @@ http {
 
 	gzip on;
 	gzip_vary on;
-	gzip_types application/javascript text/css;
+	gzip_comp_level 6;
+	gzip_min_length 1024;
+	# nginx 1.21.1 起 mime.types 把 .js 标成 text/javascript，
+	# 只写 application/javascript 会导致前端 JS 完全不压缩，两个都要留。
+	# text/html 是内置的，不用也不能写在这里。
+	gzip_types
+		text/javascript
+		application/javascript
+		text/css
+		application/json
+		image/svg+xml
+		text/plain;
 
 	log_format main '$remote_addr - $remote_user [$time_local] "$request" '
 			'$status $body_bytes_sent "$http_referer" '