/* ============================================================
   词汇学习系统 · Design Tokens
   ============================================================ */
:root {
  /* Brand */
  --navy:       #0d2137;
  --navy2:      #162d47;
  --blue:       #1a6fc4;
  --blue-mid:   #145da8;
  --blue-l:     #d0e8fa;
  --blue-p:     #eef6fd;

  /* Semantic */
  --green:      #1a7a43;
  --green-l:    #e4f7ec;
  --red:        #c0392b;
  --red-l:      #fdecea;
  --amber:      #b7770d;
  --amber-l:    #fdf3dc;
  --purple:     #6c3fc5;
  --purple-l:   #ede6fb;
  --teal:       #0f766e;
  --teal-l:     #e0f5f4;

  /* Neutrals */
  --g900:  #1a2332;
  --g700:  #3d5166;
  --g500:  #7a8fa6;
  --g300:  #d0dae6;
  --g100:  #f0f4f8;
  --g50:   #f5f4f0;
  --white: #ffffff;

  /* Typography */
  --font: 'PingFang SC','Noto Sans SC','Microsoft YaHei',system-ui,sans-serif;
  --font-mono: 'SF Mono','Fira Code','Courier New',monospace;

  /* Radius */
  --r-sm:  6px;
  --r:     10px;
  --r-lg:  16px;
  --r-xl:  22px;

  /* Shadow */
  --shadow: 0 2px 12px rgba(0,0,0,0.07);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.10);

  /* Spacing */
  --sidebar-w: 260px;
  --topbar-h:  60px;
  --content-pad: 32px;
}