超简洁外观

/*隐藏前进后退图标*/
#back-button { display: none !important }
#forward-button { display: none !important }
    
/*隐藏网站信息图标*/
#identity-box { display: none !important }
    
/*隐藏盾形图标*/
#tracking-protection-icon-container { display: none !important }
    
/*隐藏标签栏左右空白*/
.titlebar-spacer { display: none !important; }
  
/*隐藏地址栏里面的功能按钮*/
#page-action-buttons { display: none !important }
  
/* 隐藏地址栏里面的功能按钮，悬停时显示 
#urlbar:not(:hover, [focused]) #page-action-buttons > :not([open], #urlbar-zoom-button) {
  display: none !important
}*/
    
/* 隐藏所有非固定标签页的关闭按钮（默认状态） */
#tabbrowser-tabs .tabbrowser-tab:not([pinned]) .tab-close-button {
  visibility: collapse !important;
  opacity: 0 !important;
  transition: all 150ms ease-in-out !important;
}
    
/* 鼠标悬停时显示标签页的关闭按钮 */
#tabbrowser-tabs .tabbrowser-tab:not([pinned]):hover .tab-close-button {
  visibility: visible !important;
  opacity: 1 !important;
  transition: all 150ms ease-in-out !important;
}
    
/* 保持固定标签页（如钉住的标签）的关闭按钮行为不变 */
#tabbrowser-tabs .tabbrowser-tab[pinned] .tab-close-button {
  /* 固定标签页的关闭按钮保持默认行为 */
}
    
/*隐藏右键图标*/
#context-navigation,
#context-sep-navigation
{display: none !important;}
    
/*书签图标*/
#bookmarks-menu-button {
  /*list-style-image: url("chrome://browser/skin/bookmark-hollow.svg")!important;*/
  list-style-image: url("chrome://global/skin/icons/arrow-down.svg")!important;
  /*list-style-image: url("chrome://global/skin/icons/resizer.svg")!important;*/
}
    
/*扩展图标*/
#unified-extensions-button{
 list-style-image: url("chrome://global/skin/icons/chevron.svg")!important;
 }
    
/*窗口按钮间隔*/
/*.titlebar-button{ margin-inline: -5px !important; }*/
    
/*标题栏高度*/
:root {
  --tab-min-height: 34px !important;
  --tab-block-margin: 4px 6px !important;
}
  
/* 标签页样式 */
.tabbrowser-tab .tab-background {
  background-color: transparent !important;
  box-shadow: none !important;
  border: none !important;
  outline: none !important;
}
.tabbrowser-tab .tab-content {
  position: relative !important;
}
.tabbrowser-tab:not([selected]):hover .tab-content::after {
  content: '' !important;
  position: absolute !important;
  bottom: 6px !important;
  left: 1px !important;
  right: 1px !important;
  height: 2px !important;
  background-color: currentColor !important;
  opacity: 0.7 !important;
  border-radius: 0 !important;
  pointer-events: none !important;
  z-index: 1 !important;
}
.tabbrowser-tab[selected] .tab-content::after {
  content: '' !important;
  position: absolute !important;
  bottom: 6px !important;
  left: 1px !important;
  right: 1px !important;
  height: 3px !important;
  background-color: currentColor !important;
  opacity: 0.7 !important;  
  border-radius: 0 !important;
  pointer-events: none !important;
  z-index: 1 !important;
}  
    
/*===地址栏样式===*/
#nav-bar { background  : none !important; } 
#urlbar {
  .urlbar-background {
    /*box-shadow: 0 0 0 1px color-mix(in srgb, currentColor 30%, transparent) !important;*/ /*如果使用原版标签页样式，解除这行注释为佳*/
    border-radius: 3px !important; 
    --toolbar-field-background-color: var(--pf-toolbar-bgcolor);
    --toolbarbutton-border-radius: var(--pf-border-radius-md);
  }
}
#urlbar:hover .urlbar-background {
  box-shadow: 0 0 0 1px color-mix(in srgb, currentColor 70%, transparent) !important;
}
    
/*地址栏标签栏同列*/
#urlbar-container { width: auto !important; }
 :root { 
    --uc-urlbar-width: clamp(200px, 240px, 300px);
}
@media (min-width: 500px) {
    #TabsToolbar { margin-left: var(--uc-urlbar-width) !important; }
    #nav-bar { margin: calc((var(--urlbar-min-height) * -1) - 11px) calc(100vw - var(--uc-urlbar-width)) 0 0 !important; }
}