diff --git a/document/images/1.png b/document/images/1.png
deleted file mode 100644
index b57bd26a..00000000
Binary files a/document/images/1.png and /dev/null differ
diff --git a/document/images/2.png b/document/images/2.png
deleted file mode 100644
index fffa7593..00000000
Binary files a/document/images/2.png and /dev/null differ
diff --git a/document/images/category.png b/document/images/category.png
deleted file mode 100644
index cd634e6f..00000000
Binary files a/document/images/category.png and /dev/null differ
diff --git a/document/images/device-detail.png b/document/images/device-detail.png
deleted file mode 100644
index 8aa57a9e..00000000
Binary files a/document/images/device-detail.png and /dev/null differ
diff --git a/document/images/device-log.png b/document/images/device-log.png
deleted file mode 100644
index a8b28beb..00000000
Binary files a/document/images/device-log.png and /dev/null differ
diff --git a/document/images/device-statistic.png b/document/images/device-statistic.png
deleted file mode 100644
index 4244e8bf..00000000
Binary files a/document/images/device-statistic.png and /dev/null differ
diff --git a/document/images/device-status.png b/document/images/device-status.png
deleted file mode 100644
index 421583df..00000000
Binary files a/document/images/device-status.png and /dev/null differ
diff --git a/document/images/device-timer.png b/document/images/device-timer.png
deleted file mode 100644
index ff609e94..00000000
Binary files a/document/images/device-timer.png and /dev/null differ
diff --git a/document/images/device.png b/document/images/device.png
deleted file mode 100644
index 6d63cea0..00000000
Binary files a/document/images/device.png and /dev/null differ
diff --git a/document/images/emqx-client.png b/document/images/emqx-client.png
deleted file mode 100644
index 6add2f1e..00000000
Binary files a/document/images/emqx-client.png and /dev/null differ
diff --git a/document/images/emqx-plugin.png b/document/images/emqx-plugin.png
deleted file mode 100644
index 241d8e7b..00000000
Binary files a/document/images/emqx-plugin.png and /dev/null differ
diff --git a/document/images/emqx-subscribe.png b/document/images/emqx-subscribe.png
deleted file mode 100644
index 500db946..00000000
Binary files a/document/images/emqx-subscribe.png and /dev/null differ
diff --git a/document/images/flash.png b/document/images/flash.png
deleted file mode 100644
index 7780dab7..00000000
Binary files a/document/images/flash.png and /dev/null differ
diff --git a/document/images/group.png b/document/images/group.png
deleted file mode 100644
index a8003f0d..00000000
Binary files a/document/images/group.png and /dev/null differ
diff --git a/document/images/index.png b/document/images/index.png
deleted file mode 100644
index 941e40dc..00000000
Binary files a/document/images/index.png and /dev/null differ
diff --git a/document/images/integrated.png b/document/images/integrated.png
deleted file mode 100644
index 241a337c..00000000
Binary files a/document/images/integrated.png and /dev/null differ
diff --git a/document/images/message.png b/document/images/message.png
deleted file mode 100644
index da53b281..00000000
Binary files a/document/images/message.png and /dev/null differ
diff --git a/document/images/model.png b/document/images/model.png
deleted file mode 100644
index c648c19c..00000000
Binary files a/document/images/model.png and /dev/null differ
diff --git a/document/images/monitor.png b/document/images/monitor.png
deleted file mode 100644
index a1c51952..00000000
Binary files a/document/images/monitor.png and /dev/null differ
diff --git a/document/images/process.png b/document/images/process.png
deleted file mode 100644
index 9327bfa5..00000000
Binary files a/document/images/process.png and /dev/null differ
diff --git a/document/images/product-detail.png b/document/images/product-detail.png
deleted file mode 100644
index 1489edf1..00000000
Binary files a/document/images/product-detail.png and /dev/null differ
diff --git a/document/images/product.png b/document/images/product.png
deleted file mode 100644
index d61d9f6e..00000000
Binary files a/document/images/product.png and /dev/null differ
diff --git a/document/images/sys.png b/document/images/sys.png
deleted file mode 100644
index df69dfdd..00000000
Binary files a/document/images/sys.png and /dev/null differ