fix: 彻底消除滚动闪白 — 全面清除残留白色背景

- html 元素加 background-color: #0A0C16（防弹性滚动露白）
- common.css: nav-item-box、input-search、select-box 背景改深色
- theme.css: .box-shadow/.box-shadow-light 背景改深色
- 共修复 6 处白色背景残留

common/common.css

@@ -180,10 +180,10 @@
   height: 96px;
   padding: 24px 20px;
   border-radius: 3px;
-  background: #fff;
+  background: rgba(30, 41, 59, 0.6);
   display: flex;
   cursor: pointer;
-  box-shadow: 0px 0px 8px rgba(52, 52, 52, 0.08);
+  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
 }
 
 .nav-item-box:hover .title {
@@ -602,8 +602,8 @@
   margin-bottom: 20px;
   width: 30%;
   height: 56px;
-  background: #FFFFFF;
-  border: 1px solid #38BDF8;
+  background: rgba(20, 24, 36, 0.9);
+  border: 1px solid rgba(56, 189, 248, 0.4);
 }
 
 .trademark-box .input-search input {
@@ -634,8 +634,8 @@
   height: 56px;
   margin-top: 30px;
   margin-bottom: 20px;
-  background: #fff;
-  border: 1px solid #38BDF8;
+  background: rgba(20, 24, 36, 0.9);
+  border: 1px solid rgba(56, 189, 248, 0.4);
   border-left: none;
 }
 
@@ -691,8 +691,9 @@
   top: 86px;
   left: 0;
   width: calc(50% + 124px);
-  background: #FEFFFF;
-  box-shadow: 0px 5px 10px rgba(0, 0, 0, 0.1);
+  background: rgba(14, 16, 26, 0.98);
+  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.5);
+  border: 1px solid rgba(255, 255, 255, 0.08);
 }
 
 .input-search .input-search-select .select-box-item {