md/assets/css/app.css

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

input, button, textarea {
  font-family: inherit;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: normal;
}

em {
  font-style: normal !important;
}

html, body {
  height: 100%;
  font-family: 'PingFang SC', BlinkMacSystemFont, Roboto, 'Helvetica Neue', sans-serif;
}

.el-message__icon {
  display: none
}

.container {
  height: 100%;
  display: flex;
  flex-direction: column;
}

.top {
  height: 60px;
  padding: 10px 20px;
  display: flex;
  align-items: center;
  margin-right: 20px;
}

.web-title {
  margin: 0 15px 0 5px;
}

.web-icon {
  width: auto;
  height: 1.5rem;
  vertical-align: middle;
}

#editor {
  height: 100%;
  display: block;
  border: none;
  width: 100%;
  padding: 10px;
}

section {
  height: 100%;
}

.main-body {
  display: flex;
  flex-direction: column;
  padding-top: 0;
  padding-bottom: 10px;
}

.ctrl {
  flex-basis: 60px;
  flex-grow: 1;
  flex-shrink: 1;
  display: flex;
  align-items: center;
}

.preview-wrapper {
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.1);
  padding: 0;
  align-items: center;
  justify-content: center;
  display: flex;
  overflow: scroll;
}

.main-section {
  display: flex;
  height: 100%;
}

.hint {
  opacity: 0.6;
  margin: 20px 0;
}

.preview {
  margin: 0 -20px;
  width: 375px;
  padding: 20px;
  font-size: 14px;
  box-sizing: border-box;
  outline: none;
  box-shadow: 0 0 60px rgba(0, 0, 0, 0.1);
}

.preview table {
  margin-bottom: 10px;
  border-collapse: collapse;
  display: table;
  width: 100% !important;
}
/* 
.preview table tr:nth-child(even){
  background: rgb(250, 250, 250);
}
 */
.select-item-left {
  float: left;
}

.select-item-right {
  float: right;
  color: #8492a6;
  font-size: 13px;
}

.CodeMirror {
  height: 100% !important;
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.1);
  font-size: 14px;
  padding: 20px;
  width: 100% !important;
  font-family: 'PingFang SC', BlinkMacSystemFont, Roboto, 'Helvetica Neue', sans-serif;
}

/* ele ui */
.el-form-item {
  margin-bottom: 0 !important;
}

/*wechat code block*/
.rich_media_content .code-snippet *, .rich_media_content .code-snippet__fix * {
  max-width: 1000% !important;
}

.code-snippet__fix {
  word-wrap: break-word !important;
  font-size: 14px;
  margin: 10px 8px;
  color: #333;
  position: relative;
  background-color: rgba(0, 0, 0, 0.03);
  border: 1px solid #f0f0f0;
  border-radius: 2px;
  display: flex;
  line-height: 24px;
}

.code-snippet__fix .code-snippet__line-index {
  counter-reset: line;
  flex-shrink: 0;
  height: 100%;
  padding: 1em;
  list-style-type: none;
}

.code-snippet__fix .code-snippet__line-index li {
  list-style-type: none;
  text-align: right;
}

.code-snippet__fix .code-snippet__line-index li::before {
  min-width: 1.5em;
  text-align: right;
  left: -2.5em;
  counter-increment: line;
  content: counter(line);
  display: inline;
  color: rgba(0, 0, 0, 0.15);
}

.code-snippet__fix pre {
  overflow-x: auto;
  padding: 1em 1em 1em 1em;
  white-space: normal;
  flex: 1;
  -webkit-overflow-scrolling: touch;
}

.code-snippet__fix code {
  text-align: left;
  font-size: 14px;
  white-space: pre;
  display: flex;
  position: relative;
  font-family: Consolas, "Liberation Mono", Menlo, Courier, monospace;
}

::-webkit-scrollbar {
  width: 6px;
  height: 6px;
  background-color: #FFF;
}

::-webkit-scrollbar-track {
  border-radius: 6px;
  background-color: rgba(200, 200, 200, 0.3);
}

::-webkit-scrollbar-thumb {
  border-radius: 6px;
  background-color: rgba(144, 146, 152, 0.5);
  transition: background-color .3s;
}

::-webkit-scrollbar-thumb:hover {
  background-color: rgba(144, 146, 152, 0.5);
}

.CodeMirror-vscrollbar:focus {
    outline: none;
}

.CodeMirror-scroll, .preview-wrapper {
    overflow: unset!important;
    overflow-y: scroll!important;
}