diff --git a/frontend/app/trades/page.tsx b/frontend/app/trades/page.tsx
index 2c58e6c..6d451e1 100644
--- a/frontend/app/trades/page.tsx
+++ b/frontend/app/trades/page.tsx
@@ -206,26 +206,42 @@ function FlowAnalysis({ symbol }: { symbol: Symbol }) {
       ) : (
         <div className="p-4 space-y-4">
           {/* 摘要卡片 */}
-          <div className="grid grid-cols-4 gap-2">
-            <div className="bg-slate-50 rounded-lg p-2 text-center">
-              <p className="text-xs text-slate-400">主动买量</p>
-              <p className="font-mono font-semibold text-emerald-600 text-sm">{totalBuy.toFixed(1)}</p>
-            </div>
-            <div className="bg-slate-50 rounded-lg p-2 text-center">
-              <p className="text-xs text-slate-400">主动卖量</p>
-              <p className="font-mono font-semibold text-red-500 text-sm">{totalSell.toFixed(1)}</p>
-            </div>
-            <div className="bg-slate-50 rounded-lg p-2 text-center">
-              <p className="text-xs text-slate-400">Delta</p>
-              <p className={`font-mono font-semibold text-sm ${totalDelta >= 0 ? "text-emerald-600" : "text-red-500"}`}>
-                {totalDelta >= 0 ? "+" : ""}{totalDelta.toFixed(1)}
+          <div className="space-y-2">
+            <div className="flex items-center justify-between">
+              <p className="text-xs text-slate-500 font-medium">
+                统计时间窗口：
+                <span className="font-semibold text-slate-700 ml-1">
+                  {interval === "1m" ? "过去1小时" : interval === "5m" ? "过去4小时" : interval === "15m" ? "过去12小时" : "过去48小时"}
+                </span>
+                （每{interval}聚合一根，每30秒刷新）
               </p>
+              <p className="text-xs text-slate-400">单位：{symbol === "BTC" ? "BTC" : "ETH"}</p>
             </div>
-            <div className="bg-slate-50 rounded-lg p-2 text-center">
-              <p className="text-xs text-slate-400">买方占比</p>
-              <p className={`font-mono font-semibold text-sm ${buyPct >= 50 ? "text-emerald-600" : "text-red-500"}`}>
-                {buyPct.toFixed(1)}%
-              </p>
+            <div className="grid grid-cols-2 md:grid-cols-4 gap-2">
+              <div className="bg-slate-50 rounded-lg p-3">
+                <p className="text-xs text-slate-400">主动买量</p>
+                <p className="font-mono font-semibold text-emerald-600 text-base mt-0.5">{totalBuy.toFixed(1)}</p>
+                <p className="text-xs text-slate-400 mt-1">买方主动吃卖单</p>
+              </div>
+              <div className="bg-slate-50 rounded-lg p-3">
+                <p className="text-xs text-slate-400">主动卖量</p>
+                <p className="font-mono font-semibold text-red-500 text-base mt-0.5">{totalSell.toFixed(1)}</p>
+                <p className="text-xs text-slate-400 mt-1">卖方主动砸买单</p>
+              </div>
+              <div className="bg-slate-50 rounded-lg p-3">
+                <p className="text-xs text-slate-400">Delta（买-卖）</p>
+                <p className={`font-mono font-semibold text-base mt-0.5 ${totalDelta >= 0 ? "text-emerald-600" : "text-red-500"}`}>
+                  {totalDelta >= 0 ? "+" : ""}{totalDelta.toFixed(1)}
+                </p>
+                <p className="text-xs text-slate-400 mt-1">{totalDelta >= 0 ? "多头占优 ↑" : "空头占优 ↓"}</p>
+              </div>
+              <div className="bg-slate-50 rounded-lg p-3">
+                <p className="text-xs text-slate-400">买方占比</p>
+                <p className={`font-mono font-semibold text-base mt-0.5 ${buyPct >= 50 ? "text-emerald-600" : "text-red-500"}`}>
+                  {buyPct.toFixed(1)}%
+                </p>
+                <p className="text-xs text-slate-400 mt-1">{buyPct >= 55 ? "强势买盘" : buyPct >= 45 ? "买卖均衡" : "强势卖盘"}</p>
+              </div>
             </div>
           </div>