@jupyterlab/application/style/titlepanel.css

JupyterLab - Application

/*-----------------------------------------------------------------------------
| Copyright (c) Jupyter Development Team.
| Distributed under the terms of the Modified BSD License.
|----------------------------------------------------------------------------*/

:root {
  --jp-private-title-panel-height: 28px;
}

#jp-title-panel {
  min-height: var(--jp-private-title-panel-height);
  width: 100%;
  display: flex;
  background: var(--jp-layout-color1);
}

#jp-title-panel-title {
  flex: 1 1 auto;
  margin-left: 8px;
}

#jp-title-panel-title input {
  background: transparent;
  margin: 0;
  height: 28px;
  width: 100%;
  box-sizing: border-box;
  border: none;
  font-size: 18px;
  font-weight: normal;
  font-family: var(--jp-ui-font-family);
  line-height: var(--jp-private-title-panel-height);
  color: var(--jp-ui-font-color0);
  outline: none;
  appearance: none;
  -webkit-appearance: none;
  -moz-appearance: none;
}