html {
            font-size: 21px; 
            height: 100%;
        }

        body {
            font-family: Microsoft Yahei, Arial, sans-serif;
            margin: 0;
            padding: 0;
            background-color: #fff;
        }
        .navbar {
            display: flex;
            justify-content: space-between;
            align-items: center;
            background-color: #fff;
            padding: 12px 24px;
            box-shadow: 0 7px 9px rgba(0, 0, 0, 0.5);
            position: relative;
        }
        .nav-links {
            display: flex;
            gap: 1.2em;
        }

        .nav-links a {
           text-decoration: none;
           color: #6a859c;
           font-size: 1.2em;
        }
        .nav-links a:hover {
           color: #2e9dff; 
        }
        .navbar .logo {
            display: flex;
            align-items: center;
            transition: transform 0.3s ease;
        }
        .navbar .logo img {
            height: 66px;
            margin-right: 10px;
            transition: transform 0.3s ease; 
        }
        .navbar .logo p {
            font-size: 1.4em;
            margin: 0;
            color: #2e9dff;
            letter-spacing: 2px;
        }
        .navbar .logo:hover {
            transform: translateY(-3px);
        }
        .dropdown-btn {
            display: none;
            background-color: transparent;
            border: none;
            font-size: 1.5em;
            cursor: pointer;
            color: #6a859c;
        }
        @media (max-width: 780px) {
            .nav-links {
                display: none;
                flex-direction: column;
                position: absolute;
                top: 100%;
                left: 0;
                width: 100%;
                background-color: #3b99d9;
                box-shadow: 0 7px 9px rgba(0, 0, 0, 0.5);
            }

            .nav-links a {
                text-align: left;
                padding-left: 2em;
                padding-top: 0.4em;
                padding-bottom: 0.4em;
                color: white; 
            }
            .nav-links a:hover {
                color: #0088ff;
            }

            .dropdown-btn {
                display: block;
            }
            .nav-links.show {
                display: flex;
            }
        }
        .content {
            margin-top: 2.5em;
        }
        .content-title {
            color: #2e9dff;
            text-align: center;
            margin-top: 2em; 
            font-size: 2em;
            transition: font-size 0.3s ease;
        }
    
       .content-text {
            color: #6a859c;
            text-align: center;
            font-size: 1em;
            transition: font-size 0.3s ease;
        }
        .content-introduce {
            color: #6a859c;
            max-width: 500px;
            text-align: center;
            font-size: 0.9em;
            padding-left: 3em;
            padding-right: 3em;
            margin: 0 auto;
            transition: font-size 0.3s ease;
        }
        .action-button {
            font-size: 1em;
            display: block;
            width: 500px;
            margin: 2em auto; 
            padding: 0.5em auto;
            background-color: #2e9dff;
            color: white;
            text-align: center;
            text-decoration: none;
            padding: 10px 0;
            border-radius: 5px;
            transition: transform 0.5s ease;
        }
        .action-button:hover {
            transform: translateY(-3px); 
        }
        .color-block {
            width: 100%;
            height: 400px;
            background-color: #edeff2;
            margin-bottom: 0;
            padding-bottom: 0;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
        }

        .color-block-text {
            color: #6a859c;
            text-align: center;
            font-size: 1em;
            margin-bottom: 1em;
            margin-top: 0;
            transition: font-size 0.3s ease;
        }

        .color-block-buttons {
            display: flex;
            gap: 1em;
        }

        .color-block-button {
            width: 10em;
            font-size: 1em;
            background-color: #2e9dff;
            color: white;
            text-align: center;
            text-decoration: none;
            padding: 10px 20px;
            border-radius: 5px;
            transition: transform 0.5s ease;
        }
        .color-block-button:hover {
            transform: translateY(-3px); 
        }
        .site-footer {
            width: 100%;
            height: 2.5em;
            background-color: #181818;
            color: white; 
            text-align: center; 
            padding: 0.5em 0;
            margin-top: 0; 
        }
        
        @media (max-width: 780px) {
            .action-button {
                width: 300px;
                font-size: 0.8em;
            }
            .content-title {
                 font-size: 1.8em;
             }
     
            .content-text {
                 font-size: 0.8em;
             }
             .content-introduce{
                font-size: 0.8em;
            }
            .color-block-text {
                font-size: 0.8em;
            }
            .color-block-button {
                width: 9em;
                font-size: 0.6em;
            }
    }