﻿
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
	<!-- 禁止 meta refresh 自动跳首页：本页由 httpErrors 统一处理 4xx/5xx，
	     已设置 Response.Status = "404 Not Found"。若 0 秒跳转首页，
	     Google 会判定为「软 404 / 重定向」而忽略真实状态码。 -->
    <meta name="robots" content="noindex,follow">
		<meta http-equiv="refresh" content="0;URL=/index.html">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>404 - Page Not Found</title>
    <style>
        :root {
            --primary-green: #10b981; /* Emerald Green */
            --primary-blue: #3b82f6;  /* Royal Blue */
            --bg-dark: #1b6ca8;       /* Dark Slate */
            --text-light: #f8fafc;
            --text-dim: #94a3b8;
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
            background-color: var(--bg-dark);
            color: var(--text-light);
            height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            overflow: hidden;
            position: relative;
        }

        /* Animated Background Blobs */
        .background-blobs {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            z-index: 0;
            overflow: hidden;
        }

        .blob {
            position: absolute;
            border-radius: 50%;
            filter: blur(80px);
            opacity: 0.6;
            animation: move 20s infinite alternate;
        }

        .blob-1 {
            top: 10%;
            left: 20%;
            width: 400px;
            height: 400px;
            background: var(--primary-green);
            animation-duration: 25s;
        }

        .blob-2 {
            bottom: 10%;
            right: 20%;
            width: 500px;
            height: 500px;
            background: var(--primary-blue);
            animation-duration: 30s;
            animation-direction: alternate-reverse;
        }

        .blob-3 {
            top: 40%;
            left: 40%;
            width: 300px;
            height: 300px;
            background: linear-gradient(to right, var(--primary-green), var(--primary-blue));
            opacity: 0.4;
            animation-duration: 22s;
        }

        @keyframes move {
            from { transform: translate(0, 0) scale(1); }
            to { transform: translate(50px, -50px) scale(1.1); }
        }

        /* Main Content */
        .content-wrapper {
            position: relative;
            z-index: 1;
            text-align: center;
            padding: 2rem;
            max-width: 600px;
            backdrop-filter: blur(10px); /* Glassmorphism effect */
            background: rgba(15, 23, 42, 0.3);
            border-radius: 20px;
            border: 1px solid rgba(255, 255, 255, 0.1);
            box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
        }

        h1 {
            font-size: 9rem;
            font-weight: 900;
            line-height: 1;
            margin-bottom: 0.5rem;
            /* Gradient Text */
            background: linear-gradient(135deg, var(--primary-green), var(--primary-blue));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            text-shadow: 0 10px 30px rgba(16, 185, 129, 0.2);
            letter-spacing: -5px;
        }

        h2 {
            font-size: 2rem;
            margin-bottom: 1rem;
            font-weight: 700;
            color: white;
        }

        p {
            color: var(--text-dim);
            font-size: 1.125rem;
            margin-bottom: 2.5rem;
            line-height: 1.6;
        }

        .home-btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 14px 36px;
            font-size: 1rem;
            font-weight: 600;
            color: white;
            text-decoration: none;
            background: linear-gradient(90deg, var(--primary-green), var(--primary-blue));
            border-radius: 50px;
            transition: all 0.3s ease;
            box-shadow: 0 4px 15px rgba(59, 130, 246, 0.4);
            border: none;
            cursor: pointer;
        }

        .home-btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 8px 25px rgba(16, 185, 129, 0.5);
            filter: brightness(1.1);
        }

        .home-btn:active {
            transform: translateY(-1px);
        }

        /* Responsive adjustments */
        @media (max-width: 768px) {
            h1 { font-size: 6rem; }
            h2 { font-size: 1.5rem; }
            .blob { filter: blur(50px); }
        }
    </style>
</head>
<body>

    <!-- Background Elements -->
    <div class="background-blobs">
        <div class="blob blob-1"></div>
        <div class="blob blob-2"></div>
        <div class="blob blob-3"></div>
    </div>

    <!-- Main Content -->
    <div class="content-wrapper">
        <h1>404</h1>
        <h2>Page Not Found</h2>
        <p>Sorry, we couldn't find the page you're looking for. It might have been moved or deleted.</p>
        <a href="/" class="home-btn">Go Back Home</a>
    </div>

</body>
</html>
