diff --git a/freshman/宿舍规格/index.html b/freshman/宿舍规格/index.html
index 41df045..faa1cda 100644
--- a/freshman/宿舍规格/index.html
+++ b/freshman/宿舍规格/index.html
@@ -769,28 +769,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "1279347317@qq.com"; 
diff --git a/freshman/群/index.html b/freshman/群/index.html
index 7dbc523..a887a8b 100644
--- a/freshman/群/index.html
+++ b/freshman/群/index.html
@@ -561,28 +561,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "1279347317@qq.com"; 
diff --git a/rapidlinks/快速链接/index.html b/rapidlinks/快速链接/index.html
index 4aeae6f..6a7ee9b 100644
--- a/rapidlinks/快速链接/index.html
+++ b/rapidlinks/快速链接/index.html
@@ -477,28 +477,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = ""; 
diff --git a/resources/c语言/index.html b/resources/c语言/index.html
index 81274ee..3b3b43e 100644
--- a/resources/c语言/index.html
+++ b/resources/c语言/index.html
@@ -478,28 +478,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "3055938446@qq.com"; 
diff --git a/resources/大化/index.html b/resources/大化/index.html
index de1c3b7..1791e10 100644
--- a/resources/大化/index.html
+++ b/resources/大化/index.html
@@ -474,28 +474,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "3055938446@qq.com"; 
diff --git a/resources/大物活页/index.html b/resources/大物活页/index.html
index 947bf32..0c8cdd0 100644
--- a/resources/大物活页/index.html
+++ b/resources/大物活页/index.html
@@ -474,28 +474,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "3055938446@qq.com"; 
diff --git a/resources/孙子兵法/index.html b/resources/孙子兵法/index.html
index 7876cb4..125ebe3 100644
--- a/resources/孙子兵法/index.html
+++ b/resources/孙子兵法/index.html
@@ -459,28 +459,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "1547163325@qq.com"; 
diff --git a/resources/工图习题/index.html b/resources/工图习题/index.html
index 7f97c46..4af6c00 100644
--- a/resources/工图习题/index.html
+++ b/resources/工图习题/index.html
@@ -455,28 +455,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "3055938446@qq.com"; 
diff --git a/resources/数值分析/index.html b/resources/数值分析/index.html
index 6750f88..fe516b5 100644
--- a/resources/数值分析/index.html
+++ b/resources/数值分析/index.html
@@ -534,28 +534,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "1279347317@qq.com"; 
diff --git a/resources/新通用教师用书1/index.html b/resources/新通用教师用书1/index.html
index 099b2c8..296ae42 100644
--- a/resources/新通用教师用书1/index.html
+++ b/resources/新通用教师用书1/index.html
@@ -466,28 +466,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "3055938446@qq.com"; 
diff --git a/resources/概率论/index.html b/resources/概率论/index.html
index 7507339..86b36cf 100644
--- a/resources/概率论/index.html
+++ b/resources/概率论/index.html
@@ -475,28 +475,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "3055938446@qq.com"; 
diff --git a/resources/概率论习题/index.html b/resources/概率论习题/index.html
index 3799bd8..1e21f7b 100644
--- a/resources/概率论习题/index.html
+++ b/resources/概率论习题/index.html
@@ -474,28 +474,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "3055938446@qq.com"; 
diff --git a/resources/毛概复习指南/index.html b/resources/毛概复习指南/index.html
index 9f0d067..d592a6f 100644
--- a/resources/毛概复习指南/index.html
+++ b/resources/毛概复习指南/index.html
@@ -463,28 +463,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = ""; 
diff --git a/resources/画法几何ppt/index.html b/resources/画法几何ppt/index.html
index 0bdb666..26d3ab3 100644
--- a/resources/画法几何ppt/index.html
+++ b/resources/画法几何ppt/index.html
@@ -459,28 +459,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = ""; 
diff --git a/resources/线性代数/index.html b/resources/线性代数/index.html
index aa27100..47c0fba 100644
--- a/resources/线性代数/index.html
+++ b/resources/线性代数/index.html
@@ -665,28 +665,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "1279347317@qq.com"; 
diff --git a/resources/软测测验/index.html b/resources/软测测验/index.html
index 2dc83f5..694fe94 100644
--- a/resources/软测测验/index.html
+++ b/resources/软测测验/index.html
@@ -482,28 +482,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "1279347317@qq.com"; 
diff --git a/resources/食品安全/index.html b/resources/食品安全/index.html
index 99d1ce4..9c78012 100644
--- a/resources/食品安全/index.html
+++ b/resources/食品安全/index.html
@@ -459,28 +459,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "1279347317@qq.com"; 
diff --git a/resources/高数/index.html b/resources/高数/index.html
index be93a07..54bbe69 100644
--- a/resources/高数/index.html
+++ b/resources/高数/index.html
@@ -491,28 +491,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "3055938446@qq.com"; 
diff --git a/resources/高数习题/index.html b/resources/高数习题/index.html
index 6bcb1ef..1ff1256 100644
--- a/resources/高数习题/index.html
+++ b/resources/高数习题/index.html
@@ -479,28 +479,34 @@
         }
 
         async function updateAvatar(email) {
-            if (!email) {
-                console.log("Email not provided, skipping avatar update.");
-                return;
-            }
+          if (!email) {
+              console.log("Email not provided, skipping avatar update.");
+              return;
+          }
 
-            const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const avatarUrl = `https://emberimg.oss-cn-beijing.aliyuncs.com/user/${email}/avatar`;
+          const defaultAvatarUrl = "https://emberimg.oss-cn-beijing.aliyuncs.com/avatar/default.png";
+
+          try {
+              const response = await fetchNoCache(avatarUrl);
+              if (response.ok) {
+                  document.getElementById('avatar').src = avatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar updated.");
+              } else if (response.status === 404) {
+                  document.getElementById('avatar').src = defaultAvatarUrl;
+                  document.getElementById('avatar').style.display = "block";
+                  console.log("Avatar file not found, using default avatar.");
+              } else {
+                  throw new Error('Failed to fetch avatar');
+              }
+          } catch (error) {
+              document.getElementById('avatar').src = defaultAvatarUrl;
+              document.getElementById('avatar').style.display = "block";
+              console.error("Error loading avatar:", error);
+          }
+}
 
-            try {
-                const response = await fetchNoCache(avatarUrl);
-                if (response.ok) {
-                    document.getElementById('avatar').src = avatarUrl;
-                    document.getElementById('avatar').style.display = "block";
-                    console.log("Avatar updated.");
-                } else if (response.status === 404) {
-                    console.log("Avatar file not found, using default avatar.");
-                } else {
-                    throw new Error('Failed to fetch avatar');
-                }
-            } catch (error) {
-                console.error("Error loading avatar:", error);
-            }
-        }
 
         
         const email = "3055938446@qq.com";