diff --git a/package.json b/package.json
index e255dad..95fba5c 100644
--- a/package.json
+++ b/package.json
@@ -14,7 +14,7 @@
     "vue": "^2.6.6"
   },
   "devDependencies": {
-    "@fullhuman/postcss-purgecss": "^1.2.0",
+    "@fullhuman/postcss-purgecss": "^1.3.0",
     "@vue/cli-plugin-babel": "^3.11.0",
     "@vue/cli-plugin-eslint": "^3.11.0",
     "@vue/cli-service": "^3.11.0",
diff --git a/yarn.lock b/yarn.lock
index 91ceb43..d35b69c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -670,13 +670,13 @@
     lodash "^4.17.13"
     to-fast-properties "^2.0.0"
 
-"@fullhuman/postcss-purgecss@^1.2.0":
-  version "1.2.0"
-  resolved "https://registry.yarnpkg.com/@fullhuman/postcss-purgecss/-/postcss-purgecss-1.2.0.tgz#a3207a0e1812f8b56fa49fba5796a1020f2756a8"
-  integrity sha512-An05jbnZVUrX+VVNniaNQtOuo/S7tyQu5x86itXTF+7kfMaGxglFGykFX2KCt2hcbJijbvfCval9IkPO19V1KA==
+"@fullhuman/postcss-purgecss@^1.3.0":
+  version "1.3.0"
+  resolved "https://registry.yarnpkg.com/@fullhuman/postcss-purgecss/-/postcss-purgecss-1.3.0.tgz#d632900d818f4fcf4678e7326923fb838c3e03a7"
+  integrity sha512-zvfS3dPKD2FAtMcXapMJXGbDgEp9E++mLR6lTgSruv6y37uvV5xJ1crVktuC1gvnmMwsa7Zh1m05FeEiz4VnIQ==
   dependencies:
     postcss "^7.0.14"
-    purgecss "^1.3.0"
+    purgecss "^1.4.0"
 
 "@hapi/address@2.x.x":
   version "2.0.0"
@@ -6540,15 +6540,15 @@ punycode@^2.1.0, punycode@^2.1.1:
   resolved "https://registry.yarnpkg.com/punycode/-/punycode-2.1.1.tgz#b58b010ac40c22c5657616c8d2c2c02c7bf479ec"
   integrity sha512-XRsRjdf+j5ml+y/6GKHPZbrF/8p2Yga0JPtdqTIY2Xe5ohJPD9saDJJLPvp9+NSBprVvevdXZybnj2cv8OEd0A==
 
-purgecss@^1.3.0:
-  version "1.3.0"
-  resolved "https://registry.yarnpkg.com/purgecss/-/purgecss-1.3.0.tgz#fc3c303df9a74a75547545b2c0da28a9ec63da00"
-  integrity sha512-0UMnr8aUsPO7RbzAT72UELRvwMHhadtuunDm7rcgRS6b8pCVO8yglIqikiYFwQk2XP606mk+GpjI1G74Auxgtg==
+purgecss@^1.4.0:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/purgecss/-/purgecss-1.4.0.tgz#79905624ec1c6c8e1f03044bca92dd8a598ba429"
+  integrity sha512-or7/16i7O6DH+NpXqY8NCcWCc940O6PxOgjWAcMTElzgccKOJua1/n6JVtM8UYqoMMWoCyKk+CbLpo4+4mY3BQ==
   dependencies:
     glob "^7.1.3"
     postcss "^7.0.14"
     postcss-selector-parser "^6.0.0"
-    yargs "^13.2.2"
+    yargs "^14.0.0"
 
 q@^1.1.2:
   version "1.5.1"
@@ -8466,7 +8466,7 @@ yargs@12.0.5:
     y18n "^3.2.1 || ^4.0.0"
     yargs-parser "^11.1.1"
 
-yargs@^13.0.0, yargs@^13.2.2:
+yargs@^13.0.0:
   version "13.3.0"
   resolved "https://registry.yarnpkg.com/yargs/-/yargs-13.3.0.tgz#4c657a55e07e5f2cf947f8a366567c04a0dedc83"
   integrity sha512-2eehun/8ALW8TLoIl7MVaRUrg+yCnenu8B4kBlRxj3GJGDKU1Og7sMXPNm1BYyM1DOJmTZ4YeN/Nwxv+8XJsUA==
@@ -8482,6 +8482,23 @@ yargs@^13.0.0, yargs@^13.2.2:
     y18n "^4.0.0"
     yargs-parser "^13.1.1"
 
+yargs@^14.0.0:
+  version "14.0.0"
+  resolved "https://registry.yarnpkg.com/yargs/-/yargs-14.0.0.tgz#ba4cacc802b3c0b3e36a9e791723763d57a85066"
+  integrity sha512-ssa5JuRjMeZEUjg7bEL99AwpitxU/zWGAGpdj0di41pOEmJti8NR6kyUIJBkR78DTYNPZOU08luUo0GTHuB+ow==
+  dependencies:
+    cliui "^5.0.0"
+    decamelize "^1.2.0"
+    find-up "^3.0.0"
+    get-caller-file "^2.0.1"
+    require-directory "^2.1.1"
+    require-main-filename "^2.0.0"
+    set-blocking "^2.0.0"
+    string-width "^3.0.0"
+    which-module "^2.0.0"
+    y18n "^4.0.0"
+    yargs-parser "^13.1.1"
+
 yorkie@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/yorkie/-/yorkie-2.0.0.tgz#92411912d435214e12c51c2ae1093e54b6bb83d9"