style(小程序): 题目去外层大卡片融入页面背景，选项选中态统一蓝紫渐变白字并修调研页暗色残留

miniprogram/src/app.scss

@@ -249,10 +249,16 @@ page { -ms-overflow-style: none; scrollbar-width: none; }
   border-color: rgba(98, 132, 255, 0.5);
 }
 
-/* 一题一屏：卡片更突出，题目/选项更大 */
+/* 一题一屏：不再包大卡片，题目直接融入页面背景（选项保留玻璃药丸），题目/选项更大 */
 .ot-qcard.one {
-  margin-top: 8px;
-  padding: 44px 32px;
+  background: transparent;
+  backdrop-filter: none;
+  -webkit-backdrop-filter: none;
+  border: none;
+  box-shadow: none;
+  border-radius: 0;
+  margin-top: 0;
+  padding: 12px 8px 0;
 }
 
 .ot-qcard.one .ot-qtext {
@@ -304,9 +310,15 @@ page { -ms-overflow-style: none; scrollbar-width: none; }
   padding: 20px 22px;
 }
 
+/* 选中态全站统一：蓝紫渐变 + 白字 */
 .ot-opt.sel {
-  border-color: #6284ff;
-  background: rgba(99, 132, 255, 0.08);
+  border-color: transparent;
+  background: linear-gradient(135deg, #6b8bff, #8f7bff);
+  box-shadow: 0 8rpx 24rpx rgba(98, 132, 255, 0.28);
+}
+
+.ot-opt.sel .opt-text {
+  color: #ffffff;
 }
 
 .opt-key {
@@ -317,7 +329,7 @@ page { -ms-overflow-style: none; scrollbar-width: none; }
 }
 
 .ot-opt.sel .opt-key {
-  color: #6284ff;
+  color: #ffffff;
 }
 
 .opt-text {
@@ -405,7 +417,21 @@ page { -ms-overflow-style: none; scrollbar-width: none; }
 }
 .page-navbar-col { display: flex; flex-direction: column; }
 .page-navbar-no { font-family: 'BubbledotICG', monospace; color: #a3abc9; font-size: 26rpx; letter-spacing: 2rpx; line-height: 1.15; }
-.page-navbar-titlerow { display: flex; align-items: baseline; gap: 16rpx; line-height: 1.15; }
+.page-navbar-titlerow { display: flex; align-items: center; gap: 16rpx; line-height: 1.15; }
+/* 标题区返回按钮：玻璃圆形 + 线性箭头（沉浸式导航下唯一返回入口） */
+.page-navbar-back {
+  width: 56rpx; height: 56rpx; border-radius: 50%;
+  display: flex; align-items: center; justify-content: center;
+  background: rgba(255, 255, 255, 0.55);
+  backdrop-filter: blur(20rpx) saturate(160%);
+  -webkit-backdrop-filter: blur(20rpx) saturate(160%);
+  border: 1px solid rgba(99, 132, 255, 0.22);
+  color: #5a6aa3;
+  box-shadow: 0 4rpx 14rpx rgba(59, 79, 125, 0.10);
+  flex-shrink: 0;
+}
+.page-navbar-back .ic { width: 30rpx; height: 30rpx; }
+.page-navbar-back.pressed { opacity: 0.65; }
 .page-navbar-title {
   font-size: 40rpx; font-weight: 800; letter-spacing: -0.5rpx; line-height: 1.15;
   background: linear-gradient(120deg, #8fc3ff 0%, #a8a0ff 45%, #e0a0ff 80%, #7fe0ff 100%);

miniprogram/src/pages/survey/index.scss

@@ -97,7 +97,7 @@
 .sv-progress {
   height: 12rpx;
   border-radius: 999px;
-  background: rgba(255, 255, 255, 0.1);
+  background: rgba(99, 132, 255, 0.14);
   margin: 22rpx 0 18rpx;
   overflow: hidden;
 }
@@ -111,7 +111,7 @@
 .sv-part {
   display: block;
   font-size: 24rpx;
-  color: #a8c4ff;
+  color: #6284ff;
   margin-bottom: 8rpx;
 }
 
@@ -128,14 +128,16 @@
   margin: 8rpx 0 20rpx;
 }
 
-/* ---------- 问题卡片 ---------- */
+/* ---------- 题目区（不包大卡片，直接融入页面背景） ---------- */
 .sv-qcard {
-  background: rgba(255,255,255,0.55); backdrop-filter: blur(20px) saturate(160%); -webkit-backdrop-filter: blur(20px) saturate(160%);
-  border: 1rpx solid rgba(99, 132, 255, 0.14);
-  border-radius: 20px;
-  padding: 34rpx 32rpx;
-  margin-top: 8rpx;
-  box-shadow: 0 12rpx 40rpx rgba(0, 0, 0, 0.45);
+  background: transparent;
+  backdrop-filter: none;
+  -webkit-backdrop-filter: none;
+  border: none;
+  border-radius: 0;
+  padding: 16rpx 8rpx 0;
+  margin-top: 0;
+  box-shadow: none;
 }
 .sv-qnum {
   display: flex;
@@ -147,11 +149,11 @@
 }
 .sv-qnum .sv-flag {
   font-size: 20rpx;
-  color: #a8c4ff;
+  color: #6284ff;
   font-weight: 600;
 }
 .sv-check {
-  color: #a8c4ff;
+  color: #6284ff;
   font-size: 24rpx;
   display: inline-flex;
   align-items: center;
@@ -188,15 +190,15 @@
   transition: all 0.2s ease;
 }
 .sv-opt.sel {
-  border-color: #a8c4ff;
-  background: rgba(160, 180, 255,0.08);
-  box-shadow: 0 0 0 1rpx rgba(160, 180, 255,0.5), 0 0 22rpx rgba(160, 180, 255,0.14);
+  border-color: transparent;
+  background: linear-gradient(135deg, #6b8bff, #8f7bff);
+  box-shadow: 0 8rpx 24rpx rgba(98, 132, 255, 0.28);
 }
 .sv-opt-dot {
   width: 32rpx;
   height: 32rpx;
   border-radius: 50%;
-  border: 2rpx solid #5b5b5b;
+  border: 2rpx solid #8a94c0;
   flex-shrink: 0;
   margin-top: 4rpx;
   display: flex;
@@ -206,11 +208,11 @@
   color: transparent;
   transition: all 0.2s ease;
 }
+.sv-opt.sel .sv-opt-text { color: #fff; }
 .sv-opt.sel .sv-opt-dot {
-  border-color: #a8c4ff;
-  background: #a8c4ff;
-  color: #000;
-  box-shadow: 0 0 10rpx rgba(160, 180, 255,0.6);
+  border-color: #fff;
+  background: transparent;
+  color: #fff;
 }
 .sv-opt-text {
   font-size: 27rpx;
@@ -236,9 +238,9 @@
   transition: all 0.2s ease;
 }
 .sv-lk.sel {
-  border-color: #a8c4ff;
-  background: rgba(160, 180, 255,0.08);
-  box-shadow: 0 0 0 1rpx rgba(160, 180, 255,0.5), 0 0 22rpx rgba(160, 180, 255,0.14);
+  border-color: transparent;
+  background: linear-gradient(135deg, #6b8bff, #8f7bff);
+  box-shadow: 0 8rpx 24rpx rgba(98, 132, 255, 0.28);
 }
 .sv-lk-v {
   width: 48rpx;
@@ -255,9 +257,11 @@
   transition: all 0.2s ease;
 }
 .sv-lk.sel .sv-lk-v {
-  background: linear-gradient(135deg, #5b8cff, #9d6bff);
-  color: #000;
-  box-shadow: 0 0 14rpx rgba(160, 180, 255,0.55);
+  background: rgba(255, 255, 255, 0.22);
+  color: #fff;
+}
+.sv-lk.sel .sv-lk-l {
+  color: #fff;
 }
 .sv-lk-l {
   font-size: 28rpx;