html,
body {
    padding: 0;
    margin: 0;
    border: 0;
}

.lesson-banner {
    height: 500px;
    background-color: #091f40;
    background-size: cover;
    background-repeat: no-repeat;
    color: #fff;
}

/*banner图*/
.lesson .lesson-banner {
    background-position-x: center;
    background-image: url(../img/help/lesson-banner.jpg);
}

.lesson-banner-con {
    height: 500px;
    margin: 0 auto;
}

.lesson-banner-con .lesson-btn-group {
    margin-top: 44px;
}

.lesson-banner-con .title {
    font-size: 42px;
    color: #ffffff;
    line-height: 59px;
    padding-top: 148px;
}

.lesson-banner-con .sub-title {
    font-size: 32px;
    color: #ffffff;
    margin-top: 8px;
    text-align: left;
}

.lesson-banner-con .about {
    font-size: 18px;
    color: #ffffff;
    line-height: 32px;
    margin-top: 28px;
}

.lesson-title {
    margin: 60px 0 40px;
    font-size: 32px;
    font-weight: 500;
}

/*按钮*/
.lesson-btn-group {
    display: flex;
    gap: 20px;
}

.lesson-btn-primary {
    position: relative;
    display: inline-flex;
    align-items: center;
    font-size: 14px;
    line-height: 42px;
    height: 42px;
    padding: 0 62px;
    box-sizing: border-box;
    text-align: center;
    border-radius: 3px;
    transition: 0.3s;
    color: #FFFFFF;
}

.lesson-btn-icon {
    display: block;
    margin-right: 8px;
    width: 16px;
    height: 16px;
}

.lesson-btn-primary, .lesson-btn-primary:focus {
    background: #1CA5C2;
    border: 1px solid #1CA5C2;
    color: #FFFFFF;
}

.lesson-btn-ghost {
    padding: 0 34px;
    background: none;
    color: #1CA5C2;
}

.lesson-btn-primary:hover {
    background: #33AEC8;
    color: #FFFFFF;
}

.lesson-btn-primary:hover .lesson-btn-card {
    display: block;
}

.lesson-btn-card {
    display: none;
    width: 250px;
    height: 290px;
    background: #ffffff;
    position: absolute;
    top: -320px;
    left: 0;
    padding: 20px;
    box-sizing: border-box;
    box-shadow: 0px 12px 30px 0px rgba(191, 216, 224, 0.5);
}

.lesson-btn-card:after {
    position: absolute;
    content: "";
    bottom: -24px;
    left: 64px;
    border-right: 12px solid transparent;
    border-top: 12px solid #ffffff;
    border-bottom: 12px solid transparent;
    border-left: 12px solid transparent;
}

.lesson-btn-card img {
    width: 100%;
    height: 210px;
}

.lesson-btn-card p {
    margin-top: 20px;
    font-size: 14px;
    line-height: 20px;
    color: #666666 !important;
    text-align: center;
}

/*内容模块*/
.lesson-introduction {
    padding: 0 20px;
    margin-bottom: 100px;
    background-color: #FFFFFF;
}

.lesson-introduction-c {
    padding: 30px 40px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background-image: linear-gradient(135deg, rgba(28,165,194,0.12) 0%, rgba(28,165,194,0.04) 100%);
    border-radius: 10px;
}

.lesson-introduction-c + .lesson-introduction-c {
    margin-top: 40px;
}

.lesson-introduction-con .lesson-introduction-time {
    display: flex;
    align-items: center;
    margin-bottom: 32px;
    font-weight: 500;
    color: #07819d;
}

.lesson-introduction-time img {
    margin-right: 8px;
    width: 20px;
    height: 20px;
}

.lesson-introduction-tag-list {
    display: flex;
    flex-wrap: wrap;
    flex: 1;
    gap: 8px;
}

.lesson-introduction-tag {
    padding: 2px 8px;
    border-radius: 4px;
    border: 1px solid #adcfd6;
    font-size: 12px;
    line-height: 16px;
    color: #07819d;
}

.lesson-introduction-img {
    display: block;
    width: 500px;
    height: 320px;
}

.lesson-introduction-con {
    width: 480px;
}

.lesson-introduction-con h2 {
    font-size: 30px;
    color: #333333;
    line-height: 40px;
    font-weight: 500;
    text-align: left;
}

.lesson-introduction-con p,
.lesson-introduction-con .lesson-introduction-paragraph {
    line-height: 26px;
    font-size: 14px;
    margin-top: 22px;
    color: #333333;
}

.lesson-introduction-con .lesson-introduction-paragraph {
    display: flex;
    align-items: center;
    align-items: flex-start;
}

.lesson-introduction-con .lesson-btn-group {
    margin-top: 60px;
}

@media screen and (max-width: 1080px) {
    body {
        min-width: 100%;
    }

    .lesson .lesson-banner-con {
        width: 100%;
        height: auto;
        padding: 0 20px 20px;
    }

    .lesson {
        margin-top: 72px;
    }

    .lesson .lesson-banner, .lesson .lesson-banner .lesson-banner-con {
        height: auto;
        width: 100%;
    }

    .lesson .lesson-banner .title {
        font-size: 22px;
        line-height: 26px;
        padding-top: 16px;
    }

    .lesson .lesson-banner .sub-title {
        font-size: 18px;
        line-height: 20px;
        margin-top: 14px;
    }


    .lesson .lesson-banner .about {
        font-size: 14px;
        line-height: 20px;
        margin-top: 14px;
        letter-spacing: 0.6px;
    }

    .lesson .lesson-banner .btn-group {
        margin-top: 0;
        padding: 18px 0;
    }
    .lesson-introduction-c {
        padding: 10px 0 !important;
        flex-direction: column-reverse;
    }


    .lesson-introduction-con {
        width: 100% !important;
    }

    .lesson-introduction-con .lesson-btn-primary{
        flex: 1;
        padding: 0;
        justify-content: center;
    }

    .lesson-introduction-con {
        padding: 16px 20px;
        flex-direction: column;
    }

    .lesson-introduction-con .btn-group {
        display: none;
    }

    .lesson-introduction-img {
        width: 100% !important;
        height: auto !important;
        padding: 10px 20px;
    }

    .lesson-introduction-img.mobile {
        display: block;
    }

    .lesson-introduction-img.pc {
        display: none;
    }

    .lesson-introduction-con h2 {
        line-height: 26px;
        font-size: 22px;
        padding-top: 20px;
    }

    .lesson-introduction-con p {
        line-height: 20px;
        font-size: 14px;
        margin-top: 10px;
    }
}