添加登录和后端校验

完成后端设计（未在本仓库体现），通过安全的手段完成了登录鉴权

src/custom-tab-bar/index.scss

@@ -0,0 +1,62 @@
+.custom-tab-bar {
+  position: fixed;
+  bottom: 0;
+  left: 0;
+  right: 0;
+  height: 120px;
+  background: #ffffff;
+  display: flex;
+  justify-content: space-around;
+  align-items: center;
+  border-top: 3px dashed #A0C4FF;
+  padding-bottom: constant(safe-area-inset-bottom);
+  padding-bottom: env(safe-area-inset-bottom);
+  z-index: 1000;
+}
+
+/* 自定义组件样式隔离：两套主题配色在组件内自包含，不依赖全局 app.wxss */
+.custom-tab-bar.theme-dark {
+  background: #1e1e2f;
+  border-top-color: #5b8cff;
+}
+
+.tab-item {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  padding: 10px 20px;
+  position: relative;
+}
+
+.tab-icon-img {
+  width: 28px;
+  height: 28px;
+  margin-bottom: 4px;
+  transition: transform 0.2s;
+  opacity: 0.6;
+}
+
+.tab-item.active .tab-icon-img {
+  transform: scale(1.15);
+  opacity: 1;
+}
+
+.tab-label {
+  font-size: 20px;
+  color: #b08d8d;
+  transition: color 0.2s;
+}
+
+.custom-tab-bar.theme-dark .tab-label {
+  color: #a0a0c0;
+}
+
+.tab-item.active .tab-label {
+  color: #ff9a9e;
+  font-weight: 600;
+}
+
+.custom-tab-bar.theme-dark .tab-item.active .tab-label {
+  color: #ff7eb3;
+}