diff --git a/notes/pics/epoll.png b/notes/pics/epoll.png
index 93608a4f..5a664676 100644
Binary files a/notes/pics/epoll.png and b/notes/pics/epoll.png differ
diff --git a/tools/diagram/src/epoll.svg b/tools/diagram/src/epoll.svg
index 967f622d..c2891288 100644
--- a/tools/diagram/src/epoll.svg
+++ b/tools/diagram/src/epoll.svg
@@ -1,31 +1,31 @@
 <svg xmlns="http://www.w3.org/2000/svg" width="640" height="330" viewBox="0 0 640 330">
   <style>
-    text { font-family: "PingFang SC", "Microsoft YaHei", Helvetica, Arial, sans-serif; fill: #666; font-size: 12px; }
-    .title { font-weight: bold; font-size: 15px; fill: #777; text-anchor: middle; }
+    text { font-family: "PingFang SC", "Microsoft YaHei", Helvetica, Arial, sans-serif; fill: #3F3F3F; font-size: 12px; }
+    .title { font-weight: bold; font-size: 15px; fill: #333; text-anchor: middle; }
     .b { font-weight: bold; }
     .c { text-anchor: middle; }
     .e { text-anchor: end; }
     .note { fill: #C0605A; }
     .ok { fill: #6A9F68; }
-    .sub { font-size: 11px; fill: #888; }
+    .sub { font-size: 11px; fill: #6E6E6E; }
     .mono { font-family: Menlo, Consolas, monospace; }
-    .arrow { stroke: #666; stroke-width: 1.3; fill: none; marker-end: url(#a); }
+    .arrow { stroke: #555; stroke-width: 1.1; fill: none; marker-end: url(#a); }
     .red { stroke: #C0605A; marker-end: url(#r); }
     .green { stroke: #6A9F68; marker-end: url(#g); }
     .dash { stroke-dasharray: 5 4; }
-    .line { stroke: #666; stroke-width: 1.3; fill: none; }
+    .line { stroke: #555; stroke-width: 1.1; fill: none; }
     .frame { fill: none; stroke: #999; stroke-width: 1; stroke-dasharray: 4 3; }
     .shadow { fill: #DADADA; }
   </style>
   <defs>
     <marker id="a" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
-      <path d="M1,1 L9,5 L1,9" fill="none" stroke="#666" stroke-width="1.6"/>
+      <path d="M1,1.5 L9.5,5 L1,8.5 z" fill="#555"/>
     </marker>
     <marker id="r" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
-      <path d="M1,1 L9,5 L1,9" fill="none" stroke="#C0605A" stroke-width="1.6"/>
+      <path d="M1,1.5 L9.5,5 L1,8.5 z" fill="#C0605A"/>
     </marker>
     <marker id="g" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
-      <path d="M1,1 L9,5 L1,9" fill="none" stroke="#6A9F68" stroke-width="1.6"/>
+      <path d="M1,1.5 L9.5,5 L1,8.5 z" fill="#6A9F68"/>
     </marker>
   </defs>
   <rect width="100%" height="100%" fill="#FFFFFF"/>
@@ -33,16 +33,14 @@
   <text x="320" y="28" class="title">select / poll 与 epoll</text>
   <rect x="20" y="50" width="290" height="265" rx="8" class="frame"/>
   <text x="30" y="68" class="b">select / poll</text>
-  <rect x="97" y="82" width="140" height="34" rx="6" class="shadow"/>
-  <rect x="95" y="80" width="140" height="34" rx="6" fill="#B0E3E6"/>
+  <rect x="95" y="80" width="140" height="34" rx="6" fill="#C6ECE9" stroke="#7DBCB7"/>
   <text x="165" y="101.5" class="b c">用户进程</text>
   <line x1="30" y1="150" x2="300" y2="150" class="line dash"/>
   <text x="300" y="143" class="sub e">用户态</text>
   <text x="300" y="163" class="sub e">内核态</text>
   <rect x="330" y="50" width="290" height="265" rx="8" class="frame"/>
   <text x="340" y="68" class="b">epoll</text>
-  <rect x="407" y="82" width="140" height="34" rx="6" class="shadow"/>
-  <rect x="405" y="80" width="140" height="34" rx="6" fill="#B0E3E6"/>
+  <rect x="405" y="80" width="140" height="34" rx="6" fill="#C6ECE9" stroke="#7DBCB7"/>
   <text x="475" y="101.5" class="b c">用户进程</text>
   <line x1="340" y1="150" x2="610" y2="150" class="line dash"/>
   <text x="610" y="143" class="sub e">用户态</text>
@@ -50,8 +48,7 @@
   <line x1="110" y1="117" x2="110" y2="200" class="arrow "/>
   <text x="104" y="180" class="e sub">每次调用复制</text>
   <text x="104" y="194" class="e sub">全部描述符</text>
-  <rect x="72" y="205" width="160" height="40" rx="6" class="shadow"/>
-  <rect x="70" y="203" width="160" height="40" rx="6" fill="#B1DDF0"/>
+  <rect x="70" y="203" width="160" height="40" rx="6" fill="#C6E4FB" stroke="#7FB2D6"/>
   <text x="150" y="221" class="b c">遍历全部描述符</text>
   <text x="150" y="236" class="sub c">检查是否就绪</text>
   <line x1="195" y1="200" x2="195" y2="117" class="arrow "/>
@@ -73,10 +70,10 @@
   <circle cx="385" cy="275" r="9" fill="#61646B"/>
   <circle cx="415" cy="275" r="9" fill="#C0605A"/>
   <text x="400" y="300" class="c sub">红黑树：已注册描述符</text>
-  <rect x="535" y="210" width="50" height="20" rx="3" fill="#DDD7F6"/>
-  <rect x="535" y="238" width="50" height="20" rx="3" fill="#DDD7F6"/>
+  <rect x="535" y="210" width="50" height="20" rx="3" fill="#E6E3FA" stroke="#B8B0DE"/>
+  <rect x="535" y="238" width="50" height="20" rx="3" fill="#E6E3FA" stroke="#B8B0DE"/>
   <line x1="560" y1="230" x2="560" y2="237" class="arrow "/>
-  <rect x="535" y="266" width="50" height="20" rx="3" fill="#DDD7F6"/>
+  <rect x="535" y="266" width="50" height="20" rx="3" fill="#E6E3FA" stroke="#B8B0DE"/>
   <line x1="560" y1="258" x2="560" y2="265" class="arrow "/>
   <text x="560" y="297" class="c sub">就绪链表</text>
   <path d="M430,245 C470,245 490,220 532,220" class="arrow dash"/>