The level of code is not high, do not criticize. 
@font-face {
font-family: "wk";
src: url("C:/Windows/Fonts/LXGWWenKai-Regular.ttf") format("truetype");
}
body {
font-family: "wk";
font-size: 18px;
}
ol > li::marker {
color: rgb(21, 91, 218);
font-weight: bold;
}
ul >li::marker{
color: rgb(21, 91, 218);
}
h1, h2, h3, h4, h5, h6 {
color: rgb(21, 91, 218);
line-height: 30px;
}
h1 {
font-size: 1.5em;
}
h2 {
font-size: 1.4em;
}
h3 {
font-size: 1.3em;
}
h4 {
font-size: 1em;
}
h5{
font-size: 1em;
}
h6 {
font-size: 1em;
}
h1::before {
content: "h1";
position: relative;
display: inline-block;
top: -5px;;
left: 0;
color: rgb(220, 220, 220);
font-size: 15px;
line-height: 30px;
margin-right: 10px;
font-family: "wk";
}
h2::before {
content: "h2";
position: relative;
display: inline-block;
top: 0;
left: 0;
color: rgb(220, 220, 220);
font-size: 15px;
line-height: 30px;
margin-right: 10px;
font-family: "wk";
}
h3::before {
content: "h3";
position: relative;
display: inline-block;
top: 0;
left: 0;
color: rgb(220, 220, 220);
font-size: 15px;
line-height: 30px;
margin-right: 10px;
font-family: "wk";
}
h4::before {
content: "h4";
position: relative;
display: inline-block;
top: 0;
left: 0;
color: rgb(220, 220, 220);
font-size: 15px;
line-height: 30px;
margin-right: 10px;
font-family: "wk";
}
h5::before {
content: "h5";
position: relative;
display: inline-block;
top: 0;
left: 0;
color: rgb(220, 220, 220);
font-size: 15px;
line-height: 30px;
margin-right: 10px;
font-family: "wk";
}
h6::before {
content: "h6";
position: relative;
display: inline-block;
top: 0;
left: 0;
color: rgb(220, 220, 220);
font-size: 13px;
line-height: 30px;
margin-right: 10px;
font-family: "wk";
}
/* Check box */
.md-checkbox {
color: var(--joplin-color);
color: black;
}
.md-checkbox input[type=checkbox]:checked {
opacity: 0.7;
}
.jop-tinymce ul.joplin-checklist .checked,
.md-checkbox .checkbox-label-checked {
opacity: 0.5;
}
/* Bold */
b,strong{
font-weight:bolder;
color: #A63F78;
}
b::before,b::after,
strong::before,strong::after {
position: relative;
content:"**";
}
/*italic*/
em, i {
font-style: italic;
color: #e1c11f;
}
em::before,em::after,
i::before,i::after {
position: relative;
content:"*";
}
/* mark*/
mark {
background-color: #fffadc;
padding: 0 5px;
/* border-radius: 4px; */
color: var(--joplin-color);
}
mark::before,mark::after {
content: "::";
}
/* Hyphenated*/
s {
color: #c9846c !important;
}
del {
color: #c9846c !important;
}
del::before,del::after,
s::before,s::after {
position: relative;
content:"~~";
}
/*underline*/
ins,u{
color: #a17fe0;
}
/*Dividing line*/
hr {
border: none;
border-top: 2px solid #ed5a65;
margin: 1em 0;
}