diff --git a/react-complete-guide/yarn.lock b/react-complete-guide/yarn.lock
index b9760fa..d0f9ff3 100644
--- a/react-complete-guide/yarn.lock
+++ b/react-complete-guide/yarn.lock
@@ -1218,10 +1218,10 @@ bluebird@^3.4.7:
   resolved "https://registry.yarnpkg.com/bluebird/-/bluebird-3.5.5.tgz#a8d0afd73251effbbd5fe384a77d73003c17a71f"
   integrity sha512-5am6HnnfN+urzt4yfg7IgTbotDjIT/u8AJpEt0sIU9FtXfVeezXAPKswrG+xKUCOYAINpSdgZVDU6QFh+cuH3w==
 
-bn.js@^4.0.0, bn.js@^4.1.0, bn.js@^4.1.1, bn.js@^4.4.0:
-  version "4.11.8"
-  resolved "https://registry.yarnpkg.com/bn.js/-/bn.js-4.11.8.tgz#2cde09eb5ee341f484746bb0309b3253b1b1442f"
-  integrity sha512-ItfYfPLkWHUjckQCk8xC+LwxgK8NYcXywGigJgSwOP8Y2iyWT4f2vsZnoOXTTbo+o5yXmIUJ4gn5538SO5S3gA==
+bn.js@^4.0.0, bn.js@^4.1.0, bn.js@^4.1.1, bn.js@^4.11.9:
+  version "4.12.0"
+  resolved "https://registry.yarnpkg.com/bn.js/-/bn.js-4.12.0.tgz#775b3f278efbb9718eec7361f483fb36fbbfea88"
+  integrity sha512-c98Bf3tPniI+scsdk237ku1Dc3ujXQTSgyiPUDEOe7tRkhrqridvh8klBv0HCEso1OLOYcHuCv/cS6DNxKH+ZA==
 
 body-parser@1.18.3:
   version "1.18.3"
@@ -1302,7 +1302,7 @@ braces@^2.3.1, braces@^2.3.2:
     split-string "^3.0.2"
     to-regex "^3.0.1"
 
-brorand@^1.0.1:
+brorand@^1.0.1, brorand@^1.1.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/brorand/-/brorand-1.1.0.tgz#12c25efe40a45e3c323eb8675a0a0ce57b22371f"
   integrity sha1-EsJe/kCkXjwyPrhnWgoM5XsiNx8=
@@ -2455,17 +2455,17 @@ electron-to-chromium@^1.2.7, electron-to-chromium@^1.3.30:
   integrity sha512-GZAiK3oHrs0K+LwH+HD+bdjZ17v40oQQdXbbd3dgrwgbENvazrGpcuIADSAREWnxzo9gADB1evuizrbXsnoU2Q==
 
 elliptic@^6.0.0:
-  version "6.4.1"
-  resolved "https://registry.yarnpkg.com/elliptic/-/elliptic-6.4.1.tgz#c2d0b7776911b86722c632c3c06c60f2f819939a"
-  integrity sha512-BsXLz5sqX8OHcsh7CqBMztyXARmGQ3LWPtGjJi6DiJHq5C/qvi9P3OqgswKSDftbu8+IoI/QDTAm2fFnQ9SZSQ==
+  version "6.5.4"
+  resolved "https://registry.yarnpkg.com/elliptic/-/elliptic-6.5.4.tgz#da37cebd31e79a1367e941b592ed1fbebd58abbb"
+  integrity sha512-iLhC6ULemrljPZb+QutR5TQGB+pdW6KGD5RSegS+8sorOZT+rdQFbsQFJgvN3eRqNALqJer4oQ16YvJHlU8hzQ==
   dependencies:
-    bn.js "^4.4.0"
-    brorand "^1.0.1"
+    bn.js "^4.11.9"
+    brorand "^1.1.0"
     hash.js "^1.0.0"
-    hmac-drbg "^1.0.0"
-    inherits "^2.0.1"
-    minimalistic-assert "^1.0.0"
-    minimalistic-crypto-utils "^1.0.0"
+    hmac-drbg "^1.0.1"
+    inherits "^2.0.4"
+    minimalistic-assert "^1.0.1"
+    minimalistic-crypto-utils "^1.0.1"
 
 emoji-regex@^6.1.0:
   version "6.5.1"
@@ -3568,7 +3568,7 @@ he@1.2.x:
   resolved "https://registry.yarnpkg.com/he/-/he-1.2.0.tgz#84ae65fa7eafb165fddb61566ae14baf05664f0f"
   integrity sha512-F/1DnUGPopORZi0ni+CvrCgHQ5FyEAHRLSApuYWMmrbSwoN2Mn/7k+Gl38gJnR7yyDZk6WLXwiGod1JOWNDKGw==
 
-hmac-drbg@^1.0.0:
+hmac-drbg@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/hmac-drbg/-/hmac-drbg-1.0.1.tgz#d2745701025a6c775a6c545793ed502fc0c649a1"
   integrity sha1-0nRXAQJabHdabFRXk+1QL8DGSaE=
@@ -3800,16 +3800,21 @@ inflight@^1.0.4:
     once "^1.3.0"
     wrappy "1"
 
-inherits@2, inherits@2.0.3, inherits@^2.0.1, inherits@^2.0.3, inherits@~2.0.1, inherits@~2.0.3:
-  version "2.0.3"
-  resolved "https://registry.yarnpkg.com/inherits/-/inherits-2.0.3.tgz#633c2c83e3da42a502f52466022480f4208261de"
-  integrity sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4=
+inherits@2, inherits@^2.0.1, inherits@^2.0.3, inherits@^2.0.4, inherits@~2.0.1, inherits@~2.0.3:
+  version "2.0.4"
+  resolved "https://registry.yarnpkg.com/inherits/-/inherits-2.0.4.tgz#0fa2c64f932917c3433a0ded55363aae37416b7c"
+  integrity sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==
 
 inherits@2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/inherits/-/inherits-2.0.1.tgz#b17d08d326b4423e568eff719f91b0b1cbdf69f1"
   integrity sha1-sX0I0ya0Qj5Wjv9xn5GwscvfafE=
 
+inherits@2.0.3:
+  version "2.0.3"
+  resolved "https://registry.yarnpkg.com/inherits/-/inherits-2.0.3.tgz#633c2c83e3da42a502f52466022480f4208261de"
+  integrity sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4=
+
 ini@^1.3.4, ini@~1.3.0:
   version "1.3.5"
   resolved "https://registry.yarnpkg.com/ini/-/ini-1.3.5.tgz#eee25f56db1c9ec6085e0c22778083f596abf927"
@@ -5091,7 +5096,7 @@ minimalistic-assert@^1.0.0, minimalistic-assert@^1.0.1:
   resolved "https://registry.yarnpkg.com/minimalistic-assert/-/minimalistic-assert-1.0.1.tgz#2e194de044626d4a10e7f7fbc00ce73e83e4d5c7"
   integrity sha512-UtJcAD4yEaGtjPezWuO9wC4nwUnVH/8/Im3yEHQP4b67cXlD/Qr9hdITCU1xDbSEXg2XKNaP8jsReV7vQd00/A==
 
-minimalistic-crypto-utils@^1.0.0, minimalistic-crypto-utils@^1.0.1:
+minimalistic-crypto-utils@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/minimalistic-crypto-utils/-/minimalistic-crypto-utils-1.0.1.tgz#f6c00c1c0b082246e5c4d99dfb8c7c083b2b582a"
   integrity sha1-9sAMHAsIIkblxNmd+4x8CDsrWCo=
@@ -6374,15 +6379,15 @@ react-dev-utils@^5.0.2:
     strip-ansi "3.0.1"
     text-table "0.2.0"
 
-react-dom@16.8.6:
-  version "16.8.6"
-  resolved "https://registry.yarnpkg.com/react-dom/-/react-dom-16.8.6.tgz#71d6303f631e8b0097f56165ef608f051ff6e10f"
-  integrity sha512-1nL7PIq9LTL3fthPqwkvr2zY7phIPjYrT0jp4HjyEQrEROnw4dG41VVwi/wfoCneoleqrNX7iAD+pXebJZwrwA==
+react-dom@^16.8.6:
+  version "16.14.0"
+  resolved "https://registry.yarnpkg.com/react-dom/-/react-dom-16.14.0.tgz#7ad838ec29a777fb3c75c3a190f661cf92ab8b89"
+  integrity sha512-1gCeQXDLoIqMgqD3IO2Ah9bnf0w9kzhwN5q4FGnHZ67hBm9yePzB5JJAIQCc8x3pFnNlwFq4RidZggNAAkzWWw==
   dependencies:
     loose-envify "^1.1.0"
     object-assign "^4.1.1"
     prop-types "^15.6.2"
-    scheduler "^0.13.6"
+    scheduler "^0.19.1"
 
 react-error-overlay@^4.0.1:
   version "4.0.1"
@@ -6440,15 +6445,14 @@ react-scripts@1.1.5:
   optionalDependencies:
     fsevents "^1.1.3"
 
-react@16.8.6:
-  version "16.8.6"
-  resolved "https://registry.yarnpkg.com/react/-/react-16.8.6.tgz#ad6c3a9614fd3a4e9ef51117f54d888da01f2bbe"
-  integrity sha512-pC0uMkhLaHm11ZSJULfOBqV4tIZkx87ZLvbbQYunNixAAvjnC+snJCg0XQXn9VIsttVsbZP/H/ewzgsd5fxKXw==
+react@^16.8.6:
+  version "16.14.0"
+  resolved "https://registry.yarnpkg.com/react/-/react-16.14.0.tgz#94d776ddd0aaa37da3eda8fc5b6b18a4c9a3114d"
+  integrity sha512-0X2CImDkJGApiAlcf0ODKIneSwBPhqJawOa5wCtKbu7ZECrmS26NvtSILynQ66cgkT/RJ4LidJOc3bUESwmU8g==
   dependencies:
     loose-envify "^1.1.0"
     object-assign "^4.1.1"
     prop-types "^15.6.2"
-    scheduler "^0.13.6"
 
 read-pkg-up@^1.0.1:
   version "1.0.1"
@@ -6855,10 +6859,10 @@ sax@^1.2.1, sax@^1.2.4, sax@~1.2.1:
   resolved "https://registry.yarnpkg.com/sax/-/sax-1.2.4.tgz#2816234e2378bddc4e5354fab5caa895df7100d9"
   integrity sha512-NqVDv9TpANUjFm0N8uM5GxL36UgKi9/atZw+x7YFnQ8ckwFGKrl4xX4yWtrey3UJm5nP1kUbnYgLopqWNSRhWw==
 
-scheduler@^0.13.6:
-  version "0.13.6"
-  resolved "https://registry.yarnpkg.com/scheduler/-/scheduler-0.13.6.tgz#466a4ec332467b31a91b9bf74e5347072e4cd889"
-  integrity sha512-IWnObHt413ucAYKsD9J1QShUKkbKLQQHdxRyw73sw4FN26iWr3DY/H34xGPe4nmL1DwXyWmSWmMrA9TfQbE/XQ==
+scheduler@^0.19.1:
+  version "0.19.1"
+  resolved "https://registry.yarnpkg.com/scheduler/-/scheduler-0.19.1.tgz#4f3e2ed2c1a7d65681f4c854fa8c5a1ccb40f196"
+  integrity sha512-n/zwRWRYSUj0/3g/otKDRPMh6qv2SYMWNq85IEa8iZyAv8od9zDYpGSnpBEjNgcMNq6Scbu5KfIPxNF72R/2EA==
   dependencies:
     loose-envify "^1.1.0"
     object-assign "^4.1.1"