@media only screen and (max-width: 960px) {
    #logo {
        max-width: 325px;
    }
    
    #intro-content p {
        font-size: 20px;
    }

    .app-btn {
        width: 180px;
    }
    #intro-content .intro-user-manual a {
        font-size: 16px;
    }
}

@media only screen and (max-width: 720px) {
    #intro-content h2 {
        padding: 0px 0px;
    }

    #header {
        padding: 15px 0;
        height: 72px;
    }

    #intro-content h2 {
        font-size: 36px;
    }

    #intro-content p {
        font-size: 18px;
    }
    #intro-content .intro-user-manual a {
        font-size: 14px;
    }

    #intro-content .intro-words {
        margin-bottom: 20px;
    }
}

@media only screen and (max-width: 640px) {
    #logo {
        max-width: 280px;
    }

    #intro-content .intro-text {
        margin: 0px 20px 0 20px;
    }

    #intro-content, #sign-hyosung p {
        font-size: 12px;
    }

    .app-btn {
        width: 150px;
    }
}

@media only screen and (max-width: 480px) {
    #header {
        height: 42px;
    }

    #logo {
        max-width: 215px;
    }

    #intro-content .intro-text {
        margin: 0px 12px 0 12px;
    }

    #intro-content h2 {
        font-size: 28px;
        line-height: 40px;
    }
    #intro-content .intro-words {
        margin-bottom: 16px;
    }
}

@media only screen and (max-width: 420px) {
    #intro-content p {
        font-size: 14px;
    }

    .intro-download-btns>.app-btn {
        margin-right: 20px;
    }

    .app-btn {
        width: 120px;
    }
    #intro-content .intro-user-manual a {
        font-size: 12px;
    }
}

@media only screen and (max-width: 375px) {
    #intro-content h2 {
        font-size: 24px;
    }

    #intro-content p {
        font-size: 12px;
    }
}