/* 全局样式重置 */
    /* 全局样式重置 */
    * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
    }

    body {
        font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
        /* 纯正科技蓝背景：从深空蓝到午夜蓝 */
        background: linear-gradient(135deg, #000428 0%, #004e92 100%);
        height: 100vh;
        color: #fff;
        overflow: hidden;
        position: relative;
    }

    /* --- 科技感动态背景画布 --- */
    #tech-bg {
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        z-index: 0;
    }

    /* 登录卡片容器 - 高科技玻璃拟态 */
    .login-container {
        position: relative;
        z-index: 1;
        width: 450px;
        /* 深色半透明背景 */
        background: rgba(10, 25, 47, 0.7);
        padding: 40px;
        border-radius: 12px;
        backdrop-filter: blur(15px);
        -webkit-backdrop-filter: blur(15px);
        /* 科技蓝边框 */
        border: 1px solid rgba(64, 156, 255, 0.3);
        /* 强烈的蓝色辉光阴影 */
        box-shadow: 0 0 30px rgba(0, 123, 255, 0.2), inset 0 0 20px rgba(0, 123, 255, 0.05);
        text-align: center;
        position: absolute;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%);
    }

    /* Logo与标题区域 */
    .login-header {
        margin-bottom: 30px;
    }

    .login-header h1 {
        font-size: 20px;
        font-weight: 600;
        color: #fff;
        margin-bottom: 8px;
        /* 标题文字增加蓝色霓虹光晕 */
        text-shadow: 0 0 15px rgba(64, 156, 255, 0.8);
        letter-spacing: 1px;
    }

    .login-header p {
        font-size: 14px;
        color: #8da2c7;
        letter-spacing: 2px;
        text-transform: uppercase;
    }

    /* 表单样式 */
    .form-group {
        margin-bottom: 20px;
        text-align: left;
    }

    .form-group label {
        display: block;
        margin-bottom: 8px;
        font-size: 14px;
        color: #a8b2d1;
        font-weight: 500;
    }

    .form-group input {
        width: 100%;
        padding: 12px 15px;
        background: rgba(2, 12, 27, 0.6);
        border: 1px solid #1d3f66;
        border-radius: 4px;
        font-size: 14px;
        transition: all 0.3s ease;
        outline: none;
        color: #fff;
    }

    /* 输入框聚焦时的强烈蓝光效果 */
    .form-group input:focus {
        border-color: #409cff;
        box-shadow: 0 0 15px rgba(64, 156, 255, 0.4);
        background: rgba(2, 12, 27, 0.9);
    }

    /* 验证码区域样式 */
    .captcha-group {
        display: flex;
        gap: 10px;
        align-items: center;
    }

    .captcha-group input {
        flex: 1;
    }

    .captcha-display {
        width: 120px;
        height: 42px;
        background: rgba(2, 12, 27, 0.8);
        border-radius: 4px;
        display: flex;
        justify-content: center;
        align-items: center;
        font-size: 20px;
        font-weight: bold;
        letter-spacing: 4px;
        color: #409cff;
        user-select: none;
        cursor: pointer;
        font-style: italic;
        border: 1px solid #409cff;
        text-shadow: 0 0 10px rgba(64, 156, 255, 0.8);
        transition: all 0.3s;
        box-shadow: 0 0 10px rgba(64, 156, 255, 0.2);
    }

    .captcha-display:hover {
        background: rgba(64, 156, 255, 0.1);
        box-shadow: 0 0 20px rgba(64, 156, 255, 0.4);
    }

    /* 登录按钮 - 充满能量的科技蓝 */
    .login-btn {
        width: 100%;
        padding: 12px;
        background: linear-gradient(90deg, #007bff, #00d4ff);
        color: #fff;
        border: none;
        border-radius: 4px;
        font-size: 16px;
        font-weight: bold;
        cursor: pointer;
        transition: all 0.3s;
        box-shadow: 0 0 20px rgba(0, 123, 255, 0.5);
        margin-top: 10px;
        text-transform: uppercase;
        letter-spacing: 1px;
    }

    .login-btn:hover {
        transform: translateY(-2px);
        box-shadow: 0 0 30px rgba(0, 212, 255, 0.7);
        filter: brightness(1.1);
    }
/* 底部版权信息 */
.footer {
    margin-top: 20px;
    font-size: 16px;
    color: red;
}