diff --git a/init.lua b/init.lua
index aa7d3c3..4beead9 100644
--- a/init.lua
+++ b/init.lua
@@ -29,5 +29,12 @@ require("custom-autocmd")
 require("mappings")
 -- all the plugins installed and their configurations
 vim.cmd("source " .. vim.fs.joinpath(config_dir, "viml_conf/plugins.vim"))
+
+-- diagnostic related config
+require("diagnostic-conf")
+
 -- colorscheme settings
-require("colorschemes")
+local color_scheme = require("colorschemes")
+
+-- Load a random colorscheme
+color_scheme.rand_colorscheme()
diff --git a/lua/config/lsp.lua b/lua/config/lsp.lua
index 32dc0ec..374ab88 100644
--- a/lua/config/lsp.lua
+++ b/lua/config/lsp.lua
@@ -6,18 +6,6 @@ local lspconfig = require("lspconfig")
 
 local utils = require("utils")
 
--- set quickfix list from diagnostics in a certain buffer, not the whole workspace
-local set_qflist = function(buf_num, severity)
-  local diagnostics = nil
-  diagnostics = diagnostic.get(buf_num, { severity = severity })
-
-  local qf_items = diagnostic.toqflist(diagnostics)
-  vim.fn.setqflist({}, " ", { title = "Diagnostics", items = qf_items })
-
-  -- open quickfix by default
-  vim.cmd([[copen]])
-end
-
 local custom_attach = function(client, bufnr)
   -- Mappings.
   local map = function(mode, l, r, opts)
@@ -30,23 +18,10 @@ local custom_attach = function(client, bufnr)
   map("n", "gd", vim.lsp.buf.definition, { desc = "go to definition" })
   map("n", "<C-]>", vim.lsp.buf.definition)
   map("n", "K", function()
-    vim.lsp.buf.hover { border = "single", max_height = 25 }
+    vim.lsp.buf.hover { border = "single", max_height = 25, max_width = 120 }
   end)
   map("n", "<C-k>", vim.lsp.buf.signature_help)
   map("n", "<space>rn", vim.lsp.buf.rename, { desc = "varialbe rename" })
-  map("n", "gr", vim.lsp.buf.references, { desc = "show references" })
-  map("n", "[d", function()
-    diagnostic.jump { count = -1 }
-  end, { desc = "previous diagnostic" })
-  map("n", "]d", function()
-    diagnostic.jump { count = 1 }
-  end, { desc = "next diagnostic" })
-  -- this puts diagnostics from opened files to quickfix
-  map("n", "<space>qw", diagnostic.setqflist, { desc = "put window diagnostics to qf" })
-  -- this puts diagnostics from current buffer to quickfix
-  map("n", "<space>qb", function()
-    set_qflist(bufnr)
-  end, { desc = "put buffer diagnostics to qf" })
   map("n", "<space>ca", vim.lsp.buf.code_action, { desc = "LSP code action" })
   map("n", "<space>wa", vim.lsp.buf.add_workspace_folder, { desc = "add workspace folder" })
   map("n", "<space>wr", vim.lsp.buf.remove_workspace_folder, { desc = "remove workspace folder" })
@@ -65,12 +40,6 @@ local custom_attach = function(client, bufnr)
 
   -- The blow command will highlight the current variable and its usages in the buffer.
   if client.server_capabilities.documentHighlightProvider then
-    vim.cmd([[
-      hi! link LspReferenceRead Visual
-      hi! link LspReferenceText Visual
-      hi! link LspReferenceWrite Visual
-    ]])
-
     local gid = api.nvim_create_augroup("lsp_document_highlight", { clear = true })
     api.nvim_create_autocmd("CursorHold", {
       group = gid,
@@ -255,45 +224,3 @@ if utils.executable("lua-language-server") then
     capabilities = capabilities,
   }
 end
-
--- global config for diagnostic
-diagnostic.config {
-  underline = false,
-  virtual_text = false,
-  virtual_lines = false,
-  signs = {
-    text = {
-      [diagnostic.severity.ERROR] = "🆇",
-      [diagnostic.severity.WARN] = "⚠️",
-      [diagnostic.severity.INFO] = "ℹ️",
-      [diagnostic.severity.HINT] = "",
-    },
-  },
-  severity_sort = true,
-  float = {
-    source = true,
-    header = "Diagnostics:",
-    prefix = " ",
-    border = "single",
-  },
-}
-
-api.nvim_create_autocmd("CursorHold", {
-  pattern = "*",
-  callback = function()
-    if #vim.diagnostic.get(0) == 0 then
-      return
-    end
-
-    if not vim.b.diagnostics_pos then
-      vim.b.diagnostics_pos = { nil, nil }
-    end
-
-    local cursor_pos = api.nvim_win_get_cursor(0)
-    if cursor_pos[1] ~= vim.b.diagnostics_pos[1] or cursor_pos[2] ~= vim.b.diagnostics_pos[2] then
-      diagnostic.open_float()
-    end
-
-    vim.b.diagnostics_pos = cursor_pos
-  end,
-})
diff --git a/lua/diagnostic-conf.lua b/lua/diagnostic-conf.lua
new file mode 100644
index 0000000..e50a4be
--- /dev/null
+++ b/lua/diagnostic-conf.lua
@@ -0,0 +1,66 @@
+local diagnostic = vim.diagnostic
+local api = vim.api
+
+-- global config for diagnostic
+diagnostic.config {
+  underline = false,
+  virtual_text = false,
+  virtual_lines = false,
+  signs = {
+    text = {
+      [diagnostic.severity.ERROR] = "🆇",
+      [diagnostic.severity.WARN] = "⚠️",
+      [diagnostic.severity.INFO] = "ℹ️",
+      [diagnostic.severity.HINT] = "",
+    },
+  },
+  severity_sort = true,
+  float = {
+    source = true,
+    header = "Diagnostics:",
+    prefix = " ",
+    border = "single",
+  },
+}
+
+-- set quickfix list from diagnostics in a certain buffer, not the whole workspace
+local set_qflist = function(buf_num, severity)
+  local diagnostics = nil
+  diagnostics = diagnostic.get(buf_num, { severity = severity })
+
+  local qf_items = diagnostic.toqflist(diagnostics)
+  vim.fn.setqflist({}, " ", { title = "Diagnostics", items = qf_items })
+
+  -- open quickfix by default
+  vim.cmd([[copen]])
+end
+
+-- this puts diagnostics from opened files to quickfix
+vim.keymap.set("n", "<space>qw", diagnostic.setqflist, { desc = "put window diagnostics to qf" })
+
+-- this puts diagnostics from current buffer to quickfix
+vim.keymap.set("n", "<space>qb", function()
+  set_qflist(0)
+end, { desc = "put buffer diagnostics to qf" })
+
+-- automatically show diagnostic in float win for current line
+api.nvim_create_autocmd("CursorHold", {
+  pattern = "*",
+  callback = function()
+    if #vim.diagnostic.get(0) == 0 then
+      return
+    end
+
+    if not vim.b.diagnostics_pos then
+      vim.b.diagnostics_pos = { nil, nil }
+    end
+
+    local cursor_pos = api.nvim_win_get_cursor(0)
+
+    if not vim.deep_equal(cursor_pos, vim.b.diagnostics_pos) then
+      diagnostic.open_float { width = 100 }
+    end
+
+    vim.b.diagnostics_pos = cursor_pos
+  end,
+})