@media screen and (max-width:1200px) {
.main { padding: 0 20px; }
.em .banner_contain { padding: 74px 0 74px 60px; }
.em .head { padding: 100px 0px; }
.em .section2_main { padding: 41px 0px 50px 0px; }
.em .download_btn { margin-top: 0px; }
.em .section3_right ul li { margin-top: 10px; }
.em .section3_right { padding-left: 30px; }
.em .section3 .main { padding: 50px 50px 50px 50px; }
.em .section3_contain { padding: 50px 0 0 0; }
.em .section4 .main { padding: 50px 50px; }
.em footer .main { padding: 0px 0px 15px 0px; }
.em .footer_contain .text_4 { margin-top: 0px; }
.em .top_bar_main { background-attachment: inherit !important; }
.em .section2_main .left_part { padding-left: 28px; padding-right: 20px; }
.em .right_part img { float: right; max-width: 554px; position: relative; left: 0; width: 100% }
}

@media screen and (max-width:1100px) {
.em .banner_contain h1, .em .banner_contain h1 div { font-size: 48px; line-height: 45px; border-bottom: 11px solid #c42127; }
.em .section1 { padding-top: 50px; }
.em .banner_contain { padding-top: 200px; padding-left: 62px; }
.em .banner_contain .text_1 { font-size: 19px; line-height: 26px; }
.em .head h2 { font-size: 41px; line-height: 41px; }
.em .head h2::before { width: 92px; }
.em .head h2::after { width: 300px; }
.em .study_mistakes li { width: 100%; margin-top: 40px; }
.em .head { padding: 60px 0px 40px 0px; }
.em .left_part h3, .em .left_part h3 div { font-size: 30px; line-height: 36px; }
.em .left_part h5, .em .left_part h5 div { padding: 10px 0px; }
.em .left_part ul:first-child, .em .left_part .left_part_p { padding: 0px; width: 100%; }
.em .head_section3 h2, .em .head_section3 h2 div { font-size: 33px; line-height: 38px; }
.em .section3_left { width: 100%; text-align: center; }
.em .section3_left img { float: none; display: inline-block; }
.em .section3_right { width: 100%; margin-top: 30px; }
.em .section4_head h2, .em .section4_head h2 div { font-size: 38px; }
.em .section3_right ul li::before { top: 7px; }
.em .study_mistakes li { width: 33.33%; }
}

@media screen and (max-width:1020px) {
.em .study_mistakes li h4, .em .study_mistakes li h4 div { font-size: 22px; }
}

@media screen and (max-width:991px) {
.em .study_mistakes li { width: 100%; }
.em .study_mistakes li h4, .em .study_mistakes li h4 div { font-size: 24px; }
}

@media screen and (max-width:880px) {
.em .main { width: 90%; }
.em .banner_contain { padding-top: 100px; padding-left: 50px; }
.em .left_part { width: 100%; }
.em .right_part { width: 100%; text-align: center; }
.em .right_part img { float: none; display: inline-block; }
.em .section3_left img { width: 100%; }
.em .section4_head h2, .em .section4_head h3 { margin: 20px 0px; font-size: 40px; }
.em .head_section3 .text_3 { padding: 0px; margin-top: 15px; }
.em .footer_contain { padding: 0px 20px; }
.em .left_part h3, .em .left_part h3 div { font-size: 27px; }
.em .left_part h5, .em .left_part h5 div, .em .left_part .left_part_p { font-size: 18px; }
.em .section4 .main { padding-top: 20px; }
.em .right_part { margin-right: 0px; }
.em .section2_main .left_part { width: 100%; }
.em .head_section3 { padding: 0; }
.em .section3_left { padding-left: 0; }
}

@media screen and (max-width:767px) {
.em .main { max-width: 640px; }
.em .top_bar_main { background: url(https://learn.mheducation.com/rs/303-FKF-702/images/1502721075566_01_main-banner-mobile.png); background-repeat: no-repeat; background-size: cover; }
.em .top_bar_main::before { background-image: url(https://learn.mheducation.com/rs/303-FKF-702/images/1502721075566_01_shade-mobile.png); }
.em .section3_left { padding-left: 20px; }
.em .head_section3 { padding: 95px 0 0 0; }
.em .banner_contain { padding-top: 225px; padding-left: 25px; }
.em .banner_contain h1, .em .banner_contain h1 div { font-size: 55px; line-height: 52px; }
.em .banner_contain .text_1 { font-size: 22px; line-height: 34px; padding-top: 24px; }
.em .banner_contain { padding-bottom: 44px; }
.em .section1 { padding-top: 37px; }
.em .head h2::before { width: 117px; height: 4px; bottom: -41px; }
.em .section4_head h2, .em .section4_head h3 { font-size: 40px; line-height: 42px; }
.em .section3_left { text-align: left; }
.em .left_part h3, .em .left_part h3 div { font-size: 47px; line-height: 47px; }
.em .study_mistakes li { width: 100%; margin-top: 43px; }
.em .section1 { padding-top: 37px; padding-bottom: 0; }
.em .study_mistakes { padding-bottom: 48px; }
.em .section2_main .left_part { padding-left: 23px; }
.em .section2_main { padding: 55px 0px 50px 0; }
.left_part_p { font-size: 22px; padding-top: 34px; }
.em .right_part img { float: right; max-width: 466px; position: relative; left: 26px; width: 100%; }
.em .m-t-30 { margin-top: 29px; }
.em .section3 .main { padding: 0 25px; }
.em .left_part h5, .em .left_part h5 div, .em .left_part .left_part_p { font-size: 24px; }
.em .head_section3 h2, .em .head_section3 h2 div { font-size: 48px; line-height: 38px; padding-bottom: 46px; margin-bottom: 29px; }
.em .logo { padding-top: 30px; }
.em .right_part img { float: none; display: inline-block; }
.em .full_width.m-t-30.responsive_btn { margin-top: 17px; }
.em .left_part ul:first-child, .em .left_part .left_part_p { padding-left: 98px; }
.em .left_part .left_part_p { padding-left: 83px; padding-top: 33px; }
.em .left_part ul:first-child { padding-top: 0px; }
.em .head_section3 h2, .em .head_section3 h2 div { font-size: 39px; line-height: 41px; }
.em .head_section3 h2::before { width: 95%; }
.em .head_section3 .text_3 { width: 96%; margin-top: 43px; }
.em .head_section3 h2, .em .head_section3 h2 div { margin-bottom: 0px; }
.em .section3_left img { max-width: 100%; }
.em .section3_contain { padding: 36px 0 0 0; }
.em .section3_right ul { padding-left: 0px; padding-top: 10px; }
.em .section3_right ul li { font-size: 19px; margin-top: 30px; }
.em .section3 { padding-bottom: 45px; }
.em .section4_head h2, .em .section4_head h3 { font-size: 44px; line-height: 42px; margin: 42px 0px; }
.em .section4 .main { padding-top: 57px; }
.em .head h2::after { width: 362px; }
}

@media screen and (max-width:700px) {
.em .head_section3 h2 br { display: none; }
.em .main { max-width: 100%; }
}

@media screen and (max-width:650px) {
.em .left_part ul:first-child, .em .left_part .left_part_p { padding-left: 20px; padding-top: 25px; }
.em .banner_contain h1, .em .banner_contain h1 div { font-size: 34px; line-height: 32px; border-bottom: 5px solid #c42127; padding-bottom: 15px; }
.em .banner_contain .text_1 { font-size: 17px; line-height: 23px; padding-top: 10px; }
.em .banner_contain { padding: 50px 0px; }
.em .head h2 br, .em .head h2 div br { display: none; }
.em .head { padding: 50px 0px 5px 0px; }
.em .head h2::before { bottom: -20px; }
.em .head h2::after { top: -21px; }
.em .banner_contain .text_1 br { display: none; }
.em br { display: none; }
.em .main { padding: 0px 20px; }
.em .section3 .main { padding: 20px; }
.em .right_part { padding-top: 30px; }
.em .logo img { max-width: 69px; width: 100%; }
.em .logo { padding-top: 30px; padding-left: 0; }
.em .left_part h3, .em .left_part h3 div { font-size: 36px; line-height: 40px; }
.em .head_section3 h2, .em .head_section3 h2 div { font-size: 33px; line-height: 37px; }
.em .head_section3 { padding: 30px 0px 0px 0px; }
.em .head_section3 h2, .em .head_section3 h2 div { margin-bottom: 10px; }
.em .section1 { padding-top: 0px; }
.em .section3_right ul li { margin-top: 10px; }
.em .section3_right { margin-top: 0px; }
.em .head_section3 .text_3 { margin-top: 10px; }
.em .left_part ul li, .em .left_part ul li div { margin-top: 10px; }
}

@media screen and (max-width:500px) {
.em .study_mistakes li .text_2 br { display: none; }
.em .study_mistakes li h4 br { display: none; }
.em .right_part { padding-top: 4px; }
.em .section3 { padding-bottom: 0px; }
.em .m-t-30 { margin-top: 0px; }
.em .section2_main .m-t-30 { margin-top: 20px; }
.em .footer_contain .text_4 { font-size: 13px; }
.em .section4_head .download_btn { padding: 10px 15px; }
.em .section4 .main { padding: 20px; }
.em .left_part { padding: 0px; }
.em .section3_contain { padding: 20px 0 0 0; }
.em .head_section3 .text_3 { font-size: 14px; }
.em .left_part ul li { font-size: 15px; }
.em .head_section3 h2 { padding-bottom: 25px; }
.em .download_btn { font-size: 17px; padding: 9px 23px 6px; }
.em .left_part h3, .em .left_part h3 div { font-size: 30px; line-height: 38px; }
.em .left_part ul li::before { height: 7px; width: 7px; top: 10px; }
.em .section4 .main { padding: 20px 20px 43px 20px; }
.em .section3 .main { padding: 20px 20px 43px 20px; }
.em .study_mistakes { padding-bottom: 19px; }
.em .left_part ul li, .em .left_part ul li div { padding-left: 13px; }
}

@media screen and (max-width:450px) {
.em .banner_contain h1 { font-size: 30px; }
.em .head h2 { font-size: 27px; }
.em .main { padding-left: 20px !important; padding-right: 20px !important; }
.em .main { width: 100%; }
.em .logo { margin: 0px; }
.em .head h2::after { width: 100%; }
.em .head_section3 h2 { font-size: 24px; line-height: 30px; padding-bottom: 22px; }
}

@media screen and (max-width:380px) {
.em .banner_contain .text_1 { font-size: 14px; line-height: 19px; }
.em .left_part h3 { font-size: 25px; line-height: 28px; }
.em .head_section3 .text_3 { font-size: 15px; }
.em .section4_head h2 { font-size: 25px; line-height: 26px; }
.em .section4_head h2, .em .section4_head h3 { margin: 20px 0px; }
}