body {
            background: linear-gradient(135deg, #1e1e2d 0%, #2d2d44 100%);
            display: flex;
            justify-content: center;
            align-items: center;
            min-height: 100vh;
            font-family: -apple-system, BlinkMacSystemFont, "Microsoft YaHei", sans-serif;
        }
        .login-box {
            background: #fff;
            border-radius: 12px;
            padding: 40px;
            width: 380px;
            box-shadow: 0 10px 40px rgba(0,0,0,0.3);
        }
        .login-box h2 {
            text-align: center;
            margin-bottom: 8px;
            font-size: 22px;
            color: #1e1e2d;
        }
        .login-box .subtitle {
            text-align: center;
            color: #999;
            font-size: 13px;
            margin-bottom: 28px;
        }
        .login-box .form-group {
            margin-bottom: 18px;
        }
        .login-box label {
            display: block;
            font-size: 13px;
            color: #666;
            margin-bottom: 6px;
            font-weight: 600;
        }
        .login-box .form-control {
            width: 100%;
            padding: 12px 14px;
            border: 1px solid #ddd;
            border-radius: 8px;
            font-size: 15px;
            transition: all 0.2s;
            box-sizing: border-box;
        }
        .login-box .form-control:focus {
            border-color: #1a73e8;
            box-shadow: 0 0 0 3px rgba(26,115,232,0.15);
            outline: none;
        }
        .login-box .btn-login {
            width: 100%;
            padding: 12px;
            background: #1a73e8;
            color: #fff;
            border: none;
            border-radius: 8px;
            font-size: 16px;
            font-weight: 600;
            cursor: pointer;
            transition: background 0.2s;
        }
        .login-box .btn-login:hover {
            background: #1557b0;
        }
        .login-box .btn-login:disabled {
            background: #93b8f0;
            cursor: not-allowed;
        }
        .login-box .error-msg {
            color: #dc3545;
            font-size: 13px;
            text-align: center;
            margin-top: 12px;
            display: none;
        }
        .login-box .error-msg.show {
            display: block;
        }
        .login-box .info {
            text-align: center;
            margin-top: 16px;
            font-size: 12px;
            color: #bbb;
        }
        @media (max-width: 480px) {
            .login-box { width: 90%; padding: 28px 20px; }
        }