body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            background: var(--gray-50);
            color: var(--gray-800);
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 20px;
        }

        /* ===== 登录卡片 ===== */
        .login-wrapper {
            width: 100%;
            max-width: 420px;
            animation: fadeUp 0.4s ease;
        }

        @keyframes fadeUp {
            from {
                opacity: 0;
                transform: translateY(20px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .login-card {
            background: #fff;
            border-radius: var(--radius);
            box-shadow: var(--shadow-lg);
            border: 1px solid var(--gray-200);
            padding: 40px 36px 36px;
        }

        /* 品牌头 */
        .login-brand {
            display: flex;
            align-items: center;
            gap: 14px;
            margin-bottom: 32px;
        }

        .login-brand .logo-icon {
            width: 48px;
            height: 48px;
            background: var(--primary);
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 24px;
            color: #fff;
            flex-shrink: 0;
        }

        .login-brand .brand-text {
            font-weight: 600;
            font-size: 22px;
            color: var(--gray-900);
            line-height: 1.2;
        }
        .login-brand .brand-text small {
            display: block;
            font-weight: 400;
            font-size: 13px;
            color: var(--gray-500);
            letter-spacing: 0.3px;
        }

        .login-title {
            font-size: 16px;
            font-weight: 500;
            color: var(--gray-700);
            margin-bottom: 24px;
            text-align: center;
        }

        /* ===== 表单 ===== */
        .form-group {
            margin-bottom: 20px;
        }

        .form-group label {
            display: block;
            font-size: 13px;
            font-weight: 600;
            color: var(--gray-700);
            margin-bottom: 6px;
        }

        .form-group label .required {
            color: var(--danger);
            font-weight: 700;
        }

        .form-group .input-with-icon {
            position: relative;
        }

        .form-group .input-with-icon i {
            position: absolute;
            left: 14px;
            top: 50%;
            transform: translateY(-50%);
            color: var(--gray-400);
            font-size: 16px;
        }

        .form-group input {
            width: 100%;
            padding: 10px 14px 10px 42px;
            border: 1px solid var(--gray-300);
            border-radius: 8px;
            font-size: 14px;
            color: var(--gray-800);
            background: #fff;
            transition: all var(--transition);
            outline: none;
        }

        .form-group input:focus {
            border-color: var(--primary);
            box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
        }

        .form-group input::placeholder {
            color: var(--gray-400);
        }

        /* 额外选项 (记住我 / 忘记密码) */
        .form-options {
            display: flex;
            align-items: center;
            justify-content: space-between;
            margin: 6px 0 22px;
            font-size: 13px;
        }

        .form-options label {
            display: flex;
            align-items: center;
            gap: 6px;
            color: var(--gray-600);
            cursor: pointer;
            font-weight: 400;
        }

        .form-options label input[type="checkbox"] {
            width: 16px;
            height: 16px;
            accent-color: var(--primary);
            cursor: pointer;
        }

        .form-options a {
            color: var(--primary);
            text-decoration: none;
            font-weight: 500;
        }

        .form-options a:hover {
            text-decoration: underline;
        }

        /* 登录按钮 */
        .btn-login {
            width: 100%;
            padding: 12px;
            background: var(--primary);
            color: #fff;
            border: none;
            border-radius: 8px;
            font-size: 16px;
            font-weight: 600;
            cursor: pointer;
            transition: all var(--transition);
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 10px;
        }

        .btn-login:hover {
            background: var(--primary-dark);
            box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
        }

        .btn-login:active {
            transform: scale(0.98);
        }

        /* 错误提示 */
        .login-error {
            background: var(--danger-bg);
            color: var(--danger);
            padding: 10px 14px;
            border-radius: 8px;
            font-size: 13px;
            font-weight: 500;
            margin-bottom: 16px;
            display: none;
            align-items: center;
            gap: 8px;
            border-left: 4px solid var(--danger);
        }

        .login-error.show {
            display: flex;
        }

        .demo-accounts {
            margin-top: 20px;
            padding: 14px 16px;
            background: var(--gray-50);
            border-radius: 8px;
            border: 1px solid var(--gray-200);
        }
        .demo-accounts-title {
            font-size: 12px;
            font-weight: 600;
            color: var(--gray-500);
            margin-bottom: 10px;
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .demo-account-list {
            display: flex;
            flex-direction: column;
            gap: 6px;
            font-size: 12px;
            color: var(--gray-600);
        }
        .demo-account-list code {
            background: var(--gray-200);
            padding: 1px 6px;
            border-radius: 4px;
            font-size: 11px;
            color: var(--primary);
        }

        /* ===== 响应式 ===== */
        @media (max-width: 480px) {
            .login-card {
                padding: 28px 20px;
            }
            .login-brand .brand-text {
                font-size: 18px;
            }
            .login-brand .logo-icon {
                width: 40px;
                height: 40px;
                font-size: 20px;
            }
        }