@charset "UTF-8";

/* リセット */

@import url(./reset.css);

/* 一般・共通設定 */

*,
*:before,
*:after {
    box-sizing: inherit;
}

html {
    box-sizing: border-box;
}

body {
    font-family: "ヒラギノ丸ゴ Pro W4", "ヒラギノ丸ゴ Pro", "Hiragino Maru Gothic Pro", "ヒラギノ角ゴ Pro W3", "Hiragino Kaku Gothic Pro", "HG丸ｺﾞｼｯｸM-PRO", "HGMaruGothicMPRO";
    -webkit-text-size-adjust: 100%;
    background: #ffcaca;
    line-height: 130%;
}

@media only screen and (max-width: 700px) {
    body {
        font-size: 110%;
    }
}

h3 {
    margin-top: 1em;
}

.mark_off {
    display: inline-block;
    width: 100%;
    height: 40px;
    margin: 35px 0;
    background-color: #f2b0de;
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
}

a {
    color: #127c9c;
    text-decoration: none;
}

.wraper {
    width: 100%;
    max-width: 1200px;
    text-align: center;
    line-height: 120%;
    background: #fff;
    margin: 0 auto;
    padding: 0;
    box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.2);
}


/* ヘッダの高さ分下げる*/

#top_head_margin {
    display: block;
    margin-bottom: 130px;
}

#MobileHead {
    display: none;
}

#homeimg {
    display: block;
    width: 100%;
    max-width: 1200px;
}

.triangle {
    max-width: 500px;
    width: 50vw;
}

#homemobileimg {
    display: none;
}

#works_img {
    width: 100%;
}

#works_mobile_img {
    display: none;
}

.midashi {
    display: block;
    width: 100%;
    font-size: 150%;
    font-weight: bold;
    color: #333;
    text-align: center;
    margin: 0 auto;
    margin-top: 60px;
    margin-bottom: 30px;
    padding: 15px 0;
    background-color: #ffe0e9;
    border-left: solid 4px #e03b6a;
    border-right: solid 4px #e03b6a;
    border-radius: 2px;
    box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.2);
}

.smptbe {
    width: 100%;
    border: solid 2px #888;
    table-layout: fixed;
    margin: 0 auto;
    line-height: 100%;
    margin: 5px 0;
}

.smptbe td,
th {
    border: solid 1px #888;
    text-align: center;
    padding: 5px 2px;
}

.main {
    width: 85%;
    max-width: 900px;
    text-align: left;
    margin: 0 auto;
}

.main h2 {
    display: inline-block;
    padding: 0.5em 1em;
    text-decoration: none;
    background: #688bd6;
    color: #FFF;
    border-radius: 3px;
    margin-bottom: 10px;
}

.sns_box_pc {
    display: block;
    margin-bottom: 50px;
    border-top: solid 1px #ddd;
    border-bottom: solid 1px #ddd;
    padding: 30px 0;
}

.sns_box_mobile {
    display: none;
}

.koe {
    position: relative;
    font-size: 20px;
    line-height: 130%;
    padding: 15px 0 15px 20px;
    background-color: #fafafa;
    border: 1px solid #ccc;
    border-radius: 15px;
    margin-left: 70px;
    margin-right: 5px;
    margin-bottom: 10px;
    box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.2);
}

.koe span {
    font-size: 110%;
    font-weight: bold;
    color: #c93126;
}

.koe::before {
    content: '';
    position: absolute;
    display: block;
    border-radius: 50%;
    background-color: #fafafa;
    border: 1px solid #ccc;
    left: -35px;
    bottom: 10px;
    width: 30px;
    height: 30px;
    box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.2);
}

.koe::after {
    content: '';
    position: absolute;
    display: block;
    border-radius: 50%;
    background-color: #fafafa;
    border: 1px solid #ccc;
    left: -55px;
    bottom: 5px;
    width: 15px;
    height: 15px;
    box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.2);
}

.not {
    color: #FFF;
    font-size: 15px 20px;
    line-height: 140%;
    padding: 15px;
    background-color: #333;
    border-radius: 10px;
    box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.2);
}

.Choose_box {
    line-height: 140%;
    padding: 15px 20px;
    background-color: #fff;
    border-radius: 40px;
    box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.2);
    border: 1px solid #ccc;
    margin-bottom: 15px;
}

.Choose_box span {
    font-size: 130%;
    font-weight: bold;
    color: #c93126;
}

.Choose_box img {
    float: left;
    padding-right: 10px;
    padding-bottom: 5px;
}

.Flow_box {
    line-height: 140%;
    padding: 10px;
    background-color: #fff;
    border-radius: 46px;
    box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.2);
    border: 1px solid #ccc;
}

.Flow_box td {
    vertical-align: middle;
    padding: 3px;
}

.Flow_maru {
    height: 50px;
    width: 50px;
    border-radius: 50%;
    line-height: 50px;
    text-align: center;
    background: #99ccff;
    margin-right: 5px;
}

.Otoiawase_maru {
    height: 50px;
    width: 50px;
    border-radius: 50%;
    line-height: 50px;
    text-align: center;
    background: rgb(97, 45, 2);
    color: #fff;
    margin-right: 5px;
}

.Flow_txt {
    line-height: 130%;
}

.Flow_img {
    display: block;
    margin: 0 auto;
    margin-top: 10px;
    margin-bottom: 15px;
    max-width: 200px;
    width: 40vw;
}

footer {
    width: 100%;
    max-width: 1200px;
    padding: 30px;
    text-align: center;
    background-color: #fff;
    line-height: 130%;
    margin: 0 auto;
}

.FooterLogoBox {
    color: #333;
    width: 400px;
    float: left;
    text-align: left;
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    margin-bottom: 20px;
}

footer a {
    color: #333;
    text-decoration: none;
}

.footer-popup {
    display: none;
}

.copyright {
    display: block;
    color: #333;
    padding: 10px;
    font-size: 90%;
    width: 100%;
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", "BIZ UDPGothic", Meiryo, sans-serif;
}


/* フォームの初期化 */

select {
    background-color: #EEE;
    box-shadow: none;
    padding: 5px 5px;
    height: 34px;
    border: 1px solid #bbb;
    vertical-align: 0px;
    font-size: 80%;
}


/* フォームデザイン調整 */

input[type="text"],
input[type="email"],
input[type="tel"],
textarea {
    border: 1px solid #ccc;
    -webkit-appearance: none;
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
    box-sizing: border-box;
    /* ズレ防止 */
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    margin: 0px;
    padding: 5px;
    font-size: 90%;
    width: 100%;
}


/* フォームテーブル */

.acf_table {
    width: 100%;
    margin: 0 auto;
}

.acf_th,
.acf_td {
    padding: 10px 5px 10px 5px;
    border: 1px solid #CCC;
    line-height: 140%;
}

.acf_th {
    width: 25%;
    font-weight: normal;
    text-align: left;
    vertical-align: top;
    padding-left: 20px;
    background: #f7f7f7;
}

.acf_td {
    background: #fff;
    line-height: 125%;
}

.acf_td label {
    white-space: nowrap;
}

.mars {
    vertical-align: -15%;
}

.inputWide {
    width: 50%;
}

.inputName {
    width: 20%;
}

.inputMID {
    width: 65%;
    max-width: 200px;
}

.inputMini {
    width: 2em;
}


/* モバイル時 */

@media only screen and (max-width: 700px) {
    .acf_table {
        font-size: 130%;
    }
    .acf_tr {
        display: block;
    }
    .acf_th {
        display: block;
        width: 100%;
        padding-left: 6px;
        padding-bottom: 2px;
        -webkit-box-sizing: border-box;
        -moz-box-sizing: border-box;
        box-sizing: border-box;
        border: none;
    }
    .acf_td {
        display: block;
        width: 100%;
        -webkit-box-sizing: border-box;
        -moz-box-sizing: border-box;
        box-sizing: border-box;
        padding-left: 10px;
        padding-bottom: 30px;
        border: none;
    }
    /* 文字位置調整 */
    .mars {
        vertical-align: -20;
    }
    .inputWide {
        width: 90%;
    }
    .inputName {
        width: 43%;
    }
    .form_md {
        margin: 0 10px;
        font-size: 100%;
    }
}

@media only screen and (max-width: 500px) {
    /* モバイル時に改行したい */
    .br::before {
        content: "\A";
        white-space: pre;
    }
    .mmg {
        margin-bottom: 10px;
    }
}


/* ラジオボタンズレ調整 */

.mars {
    vertical-align: -15%;
    font-size: 115%;
}


/* コンフイルムページの修正リンク右寄せ */

.a_edit {
    font-size: 70%;
    font-weight: normal;
    padding: 3px 6px;
    background: #36c43b;
    color: #fff !important;
    border-radius: 10px;
    float: right;
    text-decoration: none;
}


/* Step */

.step {
    display: inline-block;
    font-size: 100%;
    font-weight: normal;
    padding: 4px 13px 4px 15px;
    background: #0057a6;
    color: #fff !important;
    border-radius: 20px;
    margin-right: 5px;
    margin-bottom: 5px;
}

.step_txt {
    font-size: 110%;
    font-weight: bold;
}

.Q {
    display: inline-block;
    font-size: 120%;
    font-weight: bold;
    padding: 5px 6px 5px 11px;
    background: #ffb433;
    color: #fff !important;
    border-radius: 10px;
    margin: 25px 2px 5px 0;
}

.Q_txt {
    display: inline-block;
    font-size: 100%;
    font-weight: bold;
    color: #009ee7;
}


/* 必須 */

.req {
    font-size: 70%;
    font-weight: normal;
    padding: 1px 5px;
    background: #ff6666;
    color: #fff !important;
    border-radius: 2px;
    float: right;
}


/* 任意 */

.arb {
    font-size: 70%;
    font-weight: normal;
    padding: 1px 5px;
    background: #63affe;
    color: #fff !important;
    border-radius: 2px;
    float: right;
}


/* コンフイルムページの修正リンク右寄せ */

.a_edit {
    font-size: 70%;
    font-weight: normal;
    padding: 2px 7px;
    background: #36c43b;
    color: #fff !important;
    border-radius: 4px;
    float: right;
    text-decoration: none;
}


/*送信ボタンの装飾   青  グラデ*/

.b_next {
    appearance: none;
    /* safariの丸影の感じ解除 */
    -moz-appearance: none;
    -webkit-appearance: none;
    width: 40%;
    font-size: 100%;
    text-decoration: none;
    position: relative;
    display: inline-block;
    text-align: center;
    padding: 5px;
    margin: 15px 0;
    color: #fff;
    background-color: #1e9bc5;
    /*角の丸み*/
    border-radius: 4px;
    border: solid 1px rgba(255, 255, 255, 0.664);
    box-shadow: 0px 2px 2px rgba(0, 0, 0, 0.29);
}


/* モバイル時 */

@media only screen and (max-width: 700px) {
    .b_next {
        width: 100%;
        font-size: 120%;
    }
}

.b_back {
    appearance: none;
    /* safariの丸影の感じ解除 */
    -moz-appearance: none;
    -webkit-appearance: none;
    width: 40%;
    font-size: 100%;
    text-decoration: none;
    position: relative;
    display: inline-block;
    text-align: center;
    padding: 5px;
    margin: 15px 0;
    color: #333;
    background-color: #cfcfcf;
    /*角の丸み*/
    border-radius: 4px;
    border: solid 1px rgba(255, 255, 255, 0.664);
    box-shadow: 0px 2px 2px rgba(0, 0, 0, 0.29);
}

.b_touroku {
    appearance: none;
    /* safariの丸影の感じ解除 */
    -moz-appearance: none;
    -webkit-appearance: none;
    font-size: 90%;
    text-decoration: none;
    display: inline-block;
    text-align: center;
    padding: 4px 10px;
    color: #fff;
    background-color: #1e9bc5;
    /*角の丸み*/
    border-radius: 10px;
    border: solid 1px rgba(255, 255, 255, 0.664);
    box-shadow: 0px 2px 2px rgba(0, 0, 0, 0.29);
}

.b_tel {
    appearance: none;
    /* safariの丸影の感じ解除 */
    -moz-appearance: none;
    -webkit-appearance: none;
    font-size: 90%;
    text-decoration: none;
    display: inline-block;
    text-align: center;
    padding: 4px 10px;
    margin: 15px;
    color: #fff;
    background-color: #7dc51e;
    /*角の丸み*/
    border-radius: 10px;
    border: solid 1px rgba(255, 255, 255, 0.664);
    box-shadow: 0px 2px 2px rgba(0, 0, 0, 0.29);
}

.triangle {
    display: block;
    margin: 0 auto;
    width: 260px;
    margin-top: 20px;
    margin-bottom: 30px;
}

@media only screen and (max-width: 700px) {
    .triangle {
        width: 60%;
    }
}

.naka_wrap {
    width: 100%;
    max-width: 1000px;
    padding: 0 5px;
    text-align: left;
    margin: 0 auto;
    box-sizing: border-box;
}

.map_wrap {
    width: 100%;
    max-width: 900px;
    border: 1px solid #CCC;
    margin: 0 auto;
}

.map_wrap iframe {
    width: 100%;
    height: 456px;
    overflow: hidden;
    border: 1px solid #fafafa;
    padding: 0px;
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
}

.adress_box {
    width: 100%;
    margin-top: 10px;
    line-height: 150%;
    max-width: 900px;
    margin: 0 auto;
    padding-top: 5px;
}


/* 個人情報枠  プライバシーポリシー */

.Poricyframe {
    font-size: 90%;
    background-color: #FFFFFF;
    height: 145px;
    overflow: auto;
    overflow-y: scroll;
    overflow-x: hidden;
    border: 1px solid #CCC;
    padding: 5px;
    margin: 0;
    -webkit-overflow-scrolling: touch;
    /* divのスクロールをスムースに */
    z-index: 1;
}

.Poricy_about {
    padding: 5px;
    width: 100%;
    max-width: 900px;
    border: 1px solid #CCC;
    margin: 0 auto;
}

.Poricy_about li {
    list-style: none;
}


/* ▲▲▲ここまではナビゲーションに関係ない設定▲▲▲ */

.inner {
    width: 980px;
    margin: 0 auto;
}

.inner:after {
    content: "";
    clear: both;
    display: block;
}


/* header */

#top-head {
    /* display: flex;*/
    position: fixed;
    top: -100px;
    width: 100%;
    height: 130px;
    margin: 100px auto 0;
    padding: 5px 0 10px 0;
    background: #fff;
    box-shadow: 0 0 6px 0 rgba(0, 0, 0, 0.4);
    /* 解除時の動き */
    transition-duration: 0.4s;
    -webkit-transition-duration: 0.4s;
    -moz-transition-duration: 0.4s;
    z-index: 9999;
}

#top-head a,
#top-head {
    text-decoration: none;
}

#top-head .inner {
    position: relative;
}

.TopLogoBox {
    font-size: 97%;
    display: block;
    color: #333;
    width: 300px;
    float: left;
}

#TopLogo {
    width: 240px;
}

.TopBanner {
    max-width: 290px;
    width: 23vw;
    float: left;
    margin-left: 2.5vw;
}

@media screen and (max-width: 890px) {
    #TopLogo {
        width: 150px;
    }
    #global-nav ul {
        margin-right: 50px;
        margin-bottom: -28px;
    }
}

#global-nav ul {
    list-style: none;
    position: absolute;
    right: 0;
    bottom: 0;
}

#global-nav ul li {
    float: left;
    position: relative;
}

#global-nav a {
    padding: 0 5px;
    margin: 0 15px 5px 0;
    color: #333;
    font-size: 15px;
    position: relative;
    display: inline-block;
    text-decoration: none;
    /*border-left: 2px solid #009ee7; */
}

#global-nav a::after {
    position: absolute;
    bottom: -4px;
    left: 0;
    content: '';
    width: 100%;
    height: 2px;
    background: #c93126;
    transform: scale(0, 1);
    /*transform-origin: center top; センターから延びる*/
    transform-origin: left top;
    transition: transform .3s;
}

#global-nav a:hover::after {
    transform: scale(1, 1);
}


/* Toggle Button */

#nav-toggle {
    display: none;
    position: absolute;
    right: 12px;
    top: 14px;
    width: 34px;
    height: 36px;
    cursor: pointer;
    z-index: 100;
}

#nav-toggle div {
    position: relative;
}

#nav-toggle span {
    display: block;
    position: absolute;
    height: 3px;
    width: 100%;
    background: #666;
    left: 0;
    -webkit-transition: .50s ease-in-out;
    -moz-transition: .50s ease-in-out;
    transition: .50s ease-in-out;
}

#nav-toggle span:nth-child(1) {
    top: 0;
}

#nav-toggle span:nth-child(2) {
    top: 10px;
}

#nav-toggle span:nth-child(3) {
    top: 20px;
}

@media screen and (max-width: 980px) {
    article {
        padding: 0 30px;
    }
    .inner {
        width: 100%;
        padding: 0 20px;
    }
}

@media screen and (max-width: 700px) {
    #top_head_margin {
        margin-bottom: 48px;
    }
    #PcHead {
        display: none;
    }
    #MobileHead {
        display: block;
    }
    .MobileTitle {
        padding-top: 3px;
        font-weight: bold;
        line-height: 120%;
    }
    #MobileHead img {
        width: 36px;
        margin: 4px 5px 0 5px;
        float: left;
    }
    #homeimg {
        display: none;
    }
    #homemobileimg {
        display: block;
        width: 100%;
    }
    #works_img {
        display: none;
    }
    #works_mobile_img {
        display: block;
        width: 100%;
    }
    .sns_box_pc {
        display: none;
    }
    .sns_box_mobile {
        display: block;
        margin-bottom: 20px;
        border-top: solid 1px #ddd;
        border-bottom: solid 1px #ddd;
        padding: 10px 0;
    }
    #top-head,
    .inner {
        width: 100%;
        padding: 0;
    }
    #top-head {
        top: 0;
        position: fixed;
        margin-top: 0;
        height: 48px;
    }
    /* Fixed reset */
    #top-head.fixed {
        padding-top: 0;
        background: transparent;
    }
    #mobile-head {
        background: #fff;
        width: 100%;
        height: 48px;
        z-index: 999;
        position: relative;
        box-shadow: 0 0 6px 0 rgba(0, 0, 0, 0.4);
    }
    #global-nav {
        position: absolute;
        /* 開いてないときは画面外に逃がす */
        /*top: -500px;*/
        right: -100vw;
        margin-top: 5px;
        -webkit-transition: .5s ease-in-out;
        -moz-transition: .5s ease-in-out;
        transition: .5s ease-in-out;
        width: 100vw;
        height: 100vh;
        z-index: 100;
        background: rgba(0, 0, 0, 0.3);
        position: absolute;
        cursor: pointer;
        /* 押せるように */
    }
    #global-nav ul {
        list-style: none;
        position: static;
        background: #553e3e;
        width: 100vw;
        text-align: left;
        padding: 10px 0 10px 20px;
        margin-left: 50%;
        font-size: 16px;
        border: none;
    }
    #global-nav ul li {
        float: none;
        position: static;
        border: none;
    }
    #global-nav ul li:after {
        display: none;
    }
    #top-head #global-nav ul li a,
    #top-head.fixed #global-nav ul li a {
        width: 100%;
        display: block;
        color: #fff;
        padding: 10px 0;
    }
    #nav-toggle {
        display: block;
    }
    /* #nav-toggle ぐるぐるアニメーション 90度＋45度 */
    .open #nav-toggle span:nth-child(1) {
        top: 11px;
        -webkit-transform: rotate(135deg);
        -moz-transform: rotate(135deg);
        transform: rotate(135deg);
    }
    .open #nav-toggle span:nth-child(2) {
        width: 0;
        left: 50%;
    }
    .open #nav-toggle span:nth-child(3) {
        top: 11px;
        -webkit-transform: rotate(-135deg);
        -moz-transform: rotate(-135deg);
        transform: rotate(-135deg);
    }
    /* #global-nav スライドアニメーション */
    .open #global-nav {
        /* #global-nav top + #mobile-head height */
        /*-moz-transform: translateY(556px);
-webkit-transform: translateY(556px);
transform: translateY(556px);*/
        -moz-transform: translateX(-100vw);
        -webkit-transform: translateX(-100vw);
        transform: translateX(-100vw);
    }
}

#footer-nav {
    margin-bottom: 20px;
}

#footer-nav a {
    display: inline-block;
    border: none;
    border-bottom: solid 1px #666;
    font-size: 90%;
    line-height: 150%;
    margin-right: 25px;
}

@media screen and (max-width: 700px) {
    footer {
        padding: 5px;
        text-align: center;
        font-size: 90%;
        margin-bottom: 5px;
    }
    #footer-nav a {
        display: block;
        margin-bottom: 10px;
        margin-right: 0;
    }
    .FooterLogoBox {
        width: 100%;
    }
    .copyright {
        padding-bottom: 100px;
    }
    .footer-popup {
        display: block;
        width: 100%;
        position: fixed;
        left: 0;
        bottom: 0;
        padding: 0;
        z-index: 10;
        background-color: rgba(255, 255, 255, 0.7);
        box-shadow: 0 0 10px 0 rgba(0, 0, 0, 0.4);
        box-sizing: border-box;
        -moz-box-sizing: border-box;
        -webkit-box-sizing: border-box;
    }
    .footer-popup ul {
        width: 100%;
        overflow: hidden;
        display: table;
        /*table-layout: fixed;*/
        padding: 0;
        margin: 0;
        white-space: nowrap;
    }
    .footer-popup ul li {
        display: table-cell;
        list-style: none;
        padding-top: 1px;
        padding-left: 2px;
    }
    .footer-popup:last-of-type {
        /* 最後の要素だけ右にもpadding */
        padding-right: 2px;
    }
    .footer-popup img {
        width: 100%;
        margin-bottom: -2px;
    }
}

.box_Banner {
    float: left;
    margin: 0 15px 0 50px;
}

.b_Banner {
    margin: 10px;
    max-width: 400px;
    width: 30vw;
}

.sns_Banner {
    margin: 10px;
    max-width: 300px;
    width: 26vw;
}

.sns_icon {
    margin: 10px 15px;
    width: 50px;
}

.YouTube iframe {
    display: block;
    float: left;
    margin: 15px;
    width: 600px;
    height: 380px;
    border-radius: 10px;
}

@media screen and (max-width: 1050px) {
    .YouTube iframe {
        width: 480px;
        height: 260px;
    }
}

@media screen and (max-width: 821px) {
    .box_Banner {
        width: 100%;
        text-align: center;
        margin: 0;
        padding: 0;
    }
    .b_Banner {
        width: 95%;
    }
    .YouTube {
        width: 100%;
        text-align: center;
        margin: 0;
        padding: 0;
    }
    .YouTube iframe {
        width: 100%;
        height: 56vw;
        margin: 0;
        padding: 5px;
        box-sizing: border-box;
        -moz-box-sizing: border-box;
        -webkit-box-sizing: border-box;
    }
}


/* 運営会社テーブル */

.about dl {
    width: 100%;
    max-width: 900px;
    overflow: hidden;
    border: 1px solid #bbb;
    background: #fafafa;
    margin: 0 auto;
    font-size: 90%;
    line-height: 140%;
}

.about dt {
    width: 30%;
    float: left;
    padding: 4px 10px;
    border-top: 1px solid #bbb;
    box-sizing: border-box;
    text-align: center;
}

.about dd {
    margin-left: 30%;
    padding: 4px 10px;
    border-left: 1px solid #bbb;
    border-top: 1px solid #bbb;
    background: #fff;
}


/* 外枠と線が重なるので一番上のDT DDの線を消したい */

.about dt:first-child {
    border-top: none;
}


/* しかしddにfirst-childが効かない・・・
どうやらdtを挟んでいるため、隣接セレクタを使う必要があるとか
下記のように+ddに修正 */

.about dt:first-child+dd {
    border-top: none;
}

.about dd:after {
    display: block;
    content: "";
    clear: both;
}


/* モバイル時 DL調整 */

@media only screen and (max-width: 500px) {
    .about {
        padding: 0px;
    }
    .about dt {
        width: 100%;
        float: none;
    }
    .about dt:first-child {
        /*モバイル時下線追加*/
        border-bottom: 1px solid #bbb;
    }
    .about dd {
        margin-left: auto;
        border-left: none;
        padding-bottom: 20px;
    }
}