Pychram配置
灰底:【File】→【Setting(Ctrl+Alt+S)】→【Appearance & Behavior】→【Appearance】→【Theme:】
行号:【File】→【Setting(Ctrl+Alt+S)】→【Editor】→【General】→【Appearance】→【Show line numbers】
设置代码长度分隔线:【File】→【Setting(Ctrl+Alt+S)】→【Code Style】→【Right margin (columns)】