*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
  :root {
    --surface:  #ffffff;
    --border-2: #cbd5e1;
    --text:     #0f172a;
    --text-2:   #475569;
    --text-3:   #94a3b8;
    --accent:   #1d4ed8;
    --accent-h: #1e40af;
    --shadow-md: 0 4px 12px rgba(0,0,0,.10);
    --font: 'IBM Plex Sans', sans-serif;
  }
  body { font-family: var(--font); color: var(--text); font-size: 14px; line-height: 1.5; }

  #login-screen {
    min-height: 100vh; display: flex; align-items: center; justify-content: center;
    background: linear-gradient(135deg, #1d4ed8 0%, #1e3a8a 100%);
    padding: 20px;
  }
  .login-card {
    background: var(--surface); border-radius: 12px; box-shadow: var(--shadow-md);
    padding: 36px 32px; width: 100%; max-width: 360px;
  }
  .login-logo { display: flex; align-items: center; gap: 10px; margin-bottom: 24px; }
  .login-logo svg { flex-shrink: 0; }
  .login-logo span { font-weight: 600; font-size: 16px; display: block; }
  .login-logo small { color: var(--text-3); font-size: 11.5px; }
  .login-card h2 { font-size: 17px; font-weight: 600; margin-bottom: 18px; }
  .login-field { margin-bottom: 14px; }
  .login-field label { display: block; font-size: 12.5px; font-weight: 600; color: var(--text-2); margin-bottom: 5px; }
  .login-field input {
    width: 100%; padding: 9px 11px; border: 1px solid var(--border-2); border-radius: 6px;
    font-size: 13.5px; font-family: var(--font);
  }
  .login-field input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(29,78,216,.12); }
  .login-error {
    background: #fee2e2; color: #991b1b; font-size: 12.5px; padding: 8px 10px;
    border-radius: 6px; margin-bottom: 14px; display: none;
  }
  .btn {
    padding: 10px 18px; border-radius: 6px; font-family: var(--font); font-size: 13.5px;
    font-weight: 500; cursor: pointer; border: none; display: inline-flex; align-items: center;
    justify-content: center; gap: 6px; transition: background .15s; width: 100%;
  }
  .btn-primary { background: var(--accent); color: #fff; }
  .btn-primary:hover { background: var(--accent-h); }
  .btn:disabled { opacity: .55; cursor: not-allowed; }
  .login-boot { text-align: center; color: #bfdbfe; font-size: 13px; }