style(theme): 更新各主题logo及顶部栏样式，统一白底阴影效果

- 所有主题的 avue-logo 背景改为白色，并添加 0 2px 8px rgba(0,0,0,0.06) 阴影效果
- 各主题顶部栏背景及文字颜色调整，提升整体对比度与视觉统一性
- 统一调整下拉菜单、面包屑、图标等元素颜色为 rgba(0,0,0,0.85) 或 0.65，增强易读性
- 修正部分输入框和色彩选择器的边框及背景颜色，增强一致性
- index.html 添加 favicon.ico 作为页面图标
- 新增图标悬停显示浅灰圆形背景效果示例页面 icon-hover-demo.html
- icon-hover-demo.html 包含核心 CSS 代码和 Element Plus 的示例用法，方便复用和参考

src/page/index/top/index.vue

@@ -33,7 +33,7 @@
         <top-logs></top-logs>
       </div>
       <div class="top-user">
-        <img class="top-bar__img" :src="userInfo.avatar" />
+        <img class="top-bar__img" :src="userInfo.avatar"  alt=""/>
         <el-dropdown :hide-on-click="false">
           <span class="el-dropdown-link">
             {{ userInfo.real_name }}

src/page/index/top/top-theme.vue

@@ -10,8 +10,10 @@
       </el-radio-group>
     </el-dialog>
 
-    <span>
-      <i class="icon-zhuti" @click="open"></i>
+    <span class="top-theme-icon" @click="open">
+      <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+        <path d="M7 3l3 3h4l3-3 4 4-3 2v11a2 2 0 0 1-2 2H8a2 2 0 0 1-2-2V9L3 7l4-4z" />
+      </svg>
     </span>
   </div>
 </template>
@@ -116,4 +118,44 @@ export default {
 .list {
   width: 100%;
 }
+
+.top-theme-icon {
+  position: relative;
+  display: inline-flex;
+  vertical-align: middle;
+  align-items: center;
+  justify-content: center;
+  width: 36px;
+  height: 36px;
+  cursor: pointer;
+  color: rgba(0, 0, 0, 0.85);
+
+  &::before {
+    content: "";
+    position: absolute;
+    inset: 0;
+    margin: auto;
+    width: 36px;
+    height: 36px;
+    border-radius: 50%;
+    background: #f2f3f5;
+    transform: scale(0.6);
+    opacity: 0;
+    transition: transform 0.25s cubic-bezier(0.34, 1.56, 0.64, 1), opacity 0.2s ease;
+  }
+
+  &:hover::before,
+  &:focus-visible::before {
+    transform: scale(1);
+    opacity: 1;
+  }
+
+  svg {
+    position: relative;
+    z-index: 1;
+    width: 18px;
+    height: 18px;
+    pointer-events: none;
+  }
+}
 </style>

src/styles/theme/d2.scss

@@ -16,7 +16,7 @@
   }
 
   .avue-main {
-    //padding: 0 5px;
+    padding: 0 1px;
   }
 
   .avue-tags {

src/styles/top.scss

@@ -81,7 +81,6 @@
 .top-bar__right {
   height: variables.$top_height;
   position: absolute;
-  margin-top: 2px;
   top: 0;
 
   i {
@@ -121,6 +120,7 @@
   height: variables.$top_height;
   margin: 0 7px;
   font-size: 16px;
+  top: -2px;
 
   .el-badge__content.is-fixed {
     top: 12px;