remove unnecessary styles and update readme;

Author: Cube-J

1.hello-world/6.read-video-vue3/README.md

@@ -335,8 +335,6 @@ onBeforeUnmount(async () => {
   display: flex;
   justify-content: center;
   align-items: center;
-  width: 100%;
-  height: 90%;
   border: 1px solid black
 }
 </style>
@@ -381,7 +379,7 @@ const showImgDecode = () => {
 <template>
   <div className="helloWorld">
     <h1>Hello World for Vue 3 <img class="applogo" alt="Vue logo" src="../assets/logo.svg" /></h1>
-    <div class="btn-group">
+    <div>
       <button :style="{ marginRight: '10px', backgroundColor: bShowScanner ? 'rgb(255,174,55)' : 'white' }"
         @click="showScanner">Video Decode</button>
       <button :style="{ backgroundColor: bShowImgDecode ? 'rgb(255,174,55)' : 'white' }" @click="showImgDecode">Image
@@ -405,7 +403,6 @@ button {
   margin: 2vmin auto;
   text-align: center;
   font-size: medium;
-  /* height: 40vh; */
   width: 100%;
 }
 
@@ -418,7 +415,6 @@ button {
   flex-direction: column;
   align-items: center;
   justify-content: center;
-  overflow: hidden;
   width: 100%;
   height: 100%;
   color: #455a64;

1.hello-world/6.read-video-vue3/src/components/HelloWorld.vue

@@ -34,7 +34,7 @@ const showImgDecode = () => {
 <template>
   <div className="helloWorld">
     <h1>Hello World for Vue 3 <img class="applogo" alt="Vue logo" src="../assets/logo.svg" /></h1>
-    <div class="btn-group">
+    <div>
       <button :style="{ marginRight: '10px', backgroundColor: bShowScanner ? 'rgb(255,174,55)' : 'white' }"
         @click="showScanner">Video Decode</button>
       <button :style="{ backgroundColor: bShowImgDecode ? 'rgb(255,174,55)' : 'white' }" @click="showImgDecode">Image
@@ -58,7 +58,6 @@ button {
   margin: 2vmin auto;
   text-align: center;
   font-size: medium;
-  /* height: 40vh; */
   width: 100%;
 }
 
@@ -71,7 +70,6 @@ button {
   flex-direction: column;
   align-items: center;
   justify-content: center;
-  overflow: hidden;
   width: 100%;
   height: 100%;
   color: #455a64;

1.hello-world/6.read-video-vue3/src/components/ImgDecode.vue

@@ -41,8 +41,6 @@ onBeforeUnmount(async () => {
   display: flex;
   justify-content: center;
   align-items: center;
-  width: 100%;
-  height: 90%;
   border: 1px solid black
 }
 </style>