* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: "Microsoft Yahei", sans-serif;
        }

        /* ========== 全屏视频背景层（固定，内容可在其上层滚动） ========== */
        .banner {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            z-index: -1;
            overflow: hidden;
        }
        .bg-video {
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            min-width: 100%;
            min-height: 100%;
            z-index: 1;
            object-fit: cover;
        }
        .banner-mask {
            position: absolute;
            width:100%;
            height:100%;
            background: rgba(0,0,0,0.25);
            z-index: 2;
        }


        /* ===== 顶部导航栏 ===== */
        header{
            display:flex;
            justify-content: space-between;
            align-items:center;
            padding:24px 40px;
            color:#fff;
            z-index:2;
            position:relative;
        }
        .logo{
            font-size:24px;
            color:#40bfff;
            font-weight:bold;
        }
        .nav-menu a{
            color:#fff;
            text-decoration:none;
            margin-left:20px;
            font-size:16px;
        }
        .nav-menu a:hover{
            text-decoration:underline;
        }

        /* ===== 页面标题 ===== */
        .page-title{
            text-align:center;
            padding:50px 20px 30px;
            color:#fff;
            position:relative;
            z-index:2;
        }
        .page-title h1{
            font-size:44px;
            margin-bottom:14px;
        }
        .page-title p{
            font-size:17px;
            opacity:0.85;
        }

        /* ===== 投稿表单容器 ===== */
        .container{
            max-width:620px;
            margin:0 auto;
            padding:0 20px 60px;
            position:relative;
            z-index:2;
        }
        /* 磨砂卡片 */
        .glass-card{
            background: rgba(255,255,255,0.15);
            backdrop-filter: blur(14px);
            border:1px solid rgba(255,255,255,0.3);
            border-radius:14px;
            padding:34px;
            color:#fff;
        }
        .glass-card h2{
            font-size:24px;
            margin-bottom:24px;
            text-align:center;
        }

        /* 表单项通用 */
        .form-item{
            margin-bottom:18px;
        }
        .form-item label{
            display:block;
            margin-bottom:8px;
            font-size:15px;
            opacity:0.9;
        }
        .form-item input,
        .form-item select,
        .form-item textarea{
            width:100%;
            padding:12px 14px;
            background:rgba(255,255,255,0.12);
            border:1px solid rgba(255,255,255,0.25);
            border-radius:10px;
            color:#fff;
            outline:none;
            font-size:15px;
        }
        .form-item input::placeholder,
        .form-item textarea::placeholder{
            color:rgba(255,255,255,0.6);
        }
        .form-item textarea{
            min-height:180px;
            resize:vertical;
        }
        /* 下拉选项文字颜色 */
        .form-item select option{
            color:#000;
        }

        /* ===== 文件上传样式【新增】 ===== */
        .file-input-wrap{
            padding:14px;
            border:1px dashed rgba(255,255,255,0.4);
            border-radius:10px;
            text-align:center;
            cursor:pointer;
            transition:0.3s;
        }
        .file-input-wrap:hover{
            background:rgba(255,255,255,0.1);
        }
        /* 原生文件输入框隐藏 */
        #fileInput{
            display:none;
        }
        .file-tip{
            font-size:14px;
            opacity:0.8;
            margin-top:6px;
        }
        .file-list{
            margin-top:12px;
            font-size:14px;
            max-height:120px;
            overflow-y:auto;
        }

        /* 提交按钮 */
        .submit-btn{
            width:100%;
            padding:13px;
            border:none;
            border-radius:10px;
            background: rgba(92, 116, 240,0.65);
            backdrop-filter: blur(8px);
            color:#fff;
            font-size:17px;
            cursor:pointer;
            transition:0.3s;
            margin-top:10px;
        }
        .submit-btn:hover{
            background: rgba(92, 116, 240,0.85);
        }

        /* 右侧悬浮按钮（和联系我页面保持一致） */
        .float-side-btn{
            position:fixed;
            right:24px;
            top:120px;
            display:flex;
            flex-direction:column;
            gap:12px;
            z-index:99;
        }
        .float-circle-btn{
            width:40px;
            height:40px;
            border-radius:50%;
            background: rgba(255,255,255,0.15);
            backdrop-filter: blur(12px);
            border:1px solid rgba(255,255,255,0.3);
            color:#fff;
            display:flex;
            align-items:center;
            justify-content:center;
            cursor:pointer;
        }
        .float-avatar{
            position:fixed;
            right:16px;
            top:260px;
            width:60px;
            height:60px;
            border-radius:50%;
            background: rgba(255,255,255,0.15);
            backdrop-filter: blur(12px);
            border:1px solid rgba(255,255,255,0.3);
            z-index:99;
        }