.auth{min-height:100vh;display:grid;grid-template-columns:1.05fr .95fr}
  .auth-visual{
    position:relative;overflow:hidden;padding:56px 56px 48px;
    display:flex;flex-direction:column;justify-content:space-between;
    border-right:1px solid var(--line-2);
    background:
      radial-gradient(700px 500px at 20% 10%, rgba(62,232,164,.14), transparent 62%),
      radial-gradient(600px 500px at 90% 90%, rgba(47,214,214,.10), transparent 60%),
      linear-gradient(180deg, rgba(10,16,22,.7), rgba(5,7,10,.9));
  }
  .auth-visual::before{
    content:"";position:absolute;inset:0;
    background-image:linear-gradient(rgba(255,255,255,.03) 1px,transparent 1px),
                     linear-gradient(90deg,rgba(255,255,255,.03) 1px,transparent 1px);
    background-size:60px 60px;
    -webkit-mask-image:radial-gradient(circle at 40% 40%,#000,transparent 80%);
    mask-image:radial-gradient(circle at 40% 40%,#000,transparent 80%);
  }
  .auth-visual > *{position:relative;z-index:2}
  .auth-quote h2{font-size:clamp(26px,3vw,40px);line-height:1.25;margin:26px 0 18px}
  .auth-quote p{color:var(--muted);max-width:440px}
  .auth-points{display:flex;flex-direction:column;gap:14px;margin-top:30px}
  .auth-points div{display:flex;gap:12px;align-items:flex-start;font-size:14.6px}
  .auth-points svg{flex:0 0 auto;margin-top:3px;color:var(--jade)}
  .auth-main{display:flex;align-items:center;justify-content:center;padding:48px 28px}
  .auth-card{width:100%;max-width:420px}
  .auth-card h1{font-size:30px;margin-bottom:8px}
  .auth-card .sub{color:var(--muted);font-size:14.6px;margin:0 0 28px}
  .back{position:absolute;top:28px;right:32px;z-index:3}

  .field{margin-bottom:18px}
  .field label{display:block;font-size:13px;color:var(--muted);margin-bottom:8px;font-weight:500}
  .input{
    width:100%;padding:13px 15px;border-radius:10px;font-size:15px;font-family:var(--font-body);
    background:rgba(255,255,255,.03);border:1px solid var(--line-2);color:var(--fg);outline:none;transition:.25s;
  }
  .input::placeholder{color:var(--dim)}
  .input:focus{border-color:rgba(62,232,164,.55);background:rgba(62,232,164,.05);box-shadow:0 0 0 4px rgba(62,232,164,.09)}
  .code-row{display:flex;gap:10px}
  .code-row .input{flex:1;letter-spacing:.28em;font-family:var(--font-mono)}
  .code-btn{flex:0 0 auto;min-width:118px}
  .err{color:var(--danger);font-size:12.8px;margin:-6px 0 14px;display:none}
  .consent{font-size:12.4px;color:var(--dim);line-height:1.8;margin:16px 0 0;text-align:center}
  .consent a{color:var(--muted);text-decoration:underline;text-decoration-color:rgba(255,255,255,.2)}
  .consent a:hover{color:var(--jade)}
  .demo-btn{margin-top:12px}
  .or-line{display:flex;align-items:center;gap:14px;margin:20px 0 16px;color:var(--dim);font-family:var(--font-mono);font-size:11px;letter-spacing:.14em}
  .or-line::before,.or-line::after{content:"";flex:1;height:1px;background:var(--line-2)}
  .demo-tip{
    margin-top:18px;border:1px dashed rgba(62,232,164,.35);border-radius:10px;padding:13px 15px;
    font-family:var(--font-mono);font-size:12px;color:var(--muted);line-height:1.9;background:rgba(62,232,164,.04);
  }
  .demo-tip b{color:var(--jade);font-weight:500}

/* 图形验证码统一大写显示（服务端已大小写不敏感） */
#capCode{text-transform:uppercase}

/* ==========================================================================
   响应式：窄屏 / 手机
   原版没有任何断点，手机上两个面板仍然左右并排，中文被压成一列一个字。
   ========================================================================== */
@media (max-width:980px){
  .auth{grid-template-columns:1fr;min-height:100vh;min-height:100dvh}
  /* 左侧品牌区收缩为顶部一行，隐藏宣传文案 */
  .auth-visual{
    padding:18px 20px 2px;border-right:0;min-height:0;justify-content:flex-start;
    background:radial-gradient(520px 240px at 12% 0%, rgba(62,232,164,.13), transparent 70%);
  }
  .auth-visual::before{display:none}
  .auth-quote,.auth-visual .hint{display:none}
  .auth-main{padding:10px 20px 40px;align-items:center}
  .auth-card{max-width:460px}
  /* 「返回首页」回到文档流，坐在卡片顶部，不再压住标题 */
  .back{position:static;display:inline-flex;margin:0 0 16px}
}

@media (max-width:560px){
  .brand .brand-sub{display:none}
  .auth-main{padding:6px 16px 34px}
  .auth-card h1{font-size:26px;margin-bottom:6px}
  .auth-card .sub{font-size:14px;line-height:1.7;margin-bottom:20px}
  .back{margin:0 0 13px}
  .field{margin-bottom:15px}
  .field label{font-size:12.5px;margin-bottom:7px}
  /* 16px：iOS 在输入框字号 <16px 时聚焦会自动放大页面，很恼人 */
  .input{padding:14px;font-size:16px;border-radius:11px}
  .code-row{gap:8px}
  .code-row .input{letter-spacing:.2em;min-width:0}
  .code-btn{min-width:104px;padding:9px 12px}
  .cap-img{width:112px;height:41px}
  .cap-img svg{width:112px;height:41px}
  .err{margin:-4px 0 12px}
  #submitBtn{padding:15px 20px;font-size:16px;border-radius:11px}
  .or-line{margin:16px 0 12px}
  .consent{font-size:12px;margin-top:13px;line-height:1.75}
  .toast{left:16px;right:16px;bottom:16px;padding:12px 16px}
}