/*==================================================
  WHITENING
==================================================*/

.whitening-intro,
.whitening-problem,
.whitening-feature,
.whitening-type,
.whitening-recommend,
.whitening-case,
.whitening-flow,
.whitening-faq,
.whitening-cta{

    padding:80px 0;

}

.whitening-problem,
.whitening-recommend,
.whitening-faq{

    background:#fafafa;

}

.inner{

    width:min(1180px,calc(100% - 60px));

    margin:0 auto;

}

/*==================================================
  SECTION
==================================================*/

.section-heading{

    margin-bottom:55px;

}

.section-heading.center{

    text-align:center;

}

.section-heading span{

    display:inline-block;

    margin-bottom:10px;

    color:#b48a3c;

    font-size:14px;

    font-weight:700;

    letter-spacing:.18em;

    text-transform:uppercase;

}

.section-heading h2{

    margin:0;

    color:#173f5b;

    font-size:clamp(28px,2.8vw,36px);

    line-height:1.5;

}

.section-heading p{

    margin-top:24px;

    color:#555;

    font-size:17px;

    line-height:2;

}

/*==================================================
  INTRO
==================================================*/

.whitening-intro .inner{

    display:grid;

    grid-template-columns:1.1fr .9fr;

    gap:60px;

    align-items:center;

}

.whitening-intro__image img{

    width:100%;

    display:block;

    border-radius:16px;

    box-shadow:0 18px 40px rgba(0,0,0,.08);

}
/*==================================================
  PROBLEM
==================================================*/

.problem-grid{

    display:grid;

    grid-template-columns:repeat(4,1fr);

    gap:24px;

}

.problem-card{

    padding:32px 22px;

    background:#fff;

    border:1px solid #ececec;

    border-radius:16px;

    text-align:center;

    transition:.3s;

}

.problem-card:hover{

    transform:translateY(-6px);

    border-color:#173f5b;

    box-shadow:0 15px 35px rgba(0,0,0,.08);

}

.problem-card__icon{

    width:60px;

    height:60px;

    margin:0 auto 18px;

    border-radius:50%;

    background:#173f5b;

    color:#fff;

    display:flex;

    align-items:center;

    justify-content:center;

    font-size:26px;

    font-weight:700;

}

.problem-card p{

    margin:0;

    color:#173f5b;

    font-size:17px;

    line-height:1.8;

    font-weight:600;

}

/*==================================================
  FEATURE
==================================================*/

.feature-list{

    display:flex;

    flex-direction:column;

    gap:36px;

}

.feature-item{

    display:grid;

    grid-template-columns:360px 1fr;

    gap:40px;

    align-items:center;

    padding:36px;

    background:#fff;

    border:1px solid #ececec;

    border-radius:20px;

    transition:.3s;

}

.feature-item:hover{

    transform:translateY(-6px);

    border-color:#173f5b;

    box-shadow:0 18px 40px rgba(0,0,0,.08);

}

.feature-item__image{

    overflow:hidden;

    border-radius:14px;

}

.feature-item__image img{

    width:100%;

    height:240px;

    object-fit:cover;

    display:block;

    transition:.4s;

}

.feature-item:hover .feature-item__image img{

    transform:scale(1.05);

}

.feature-item__content h3{

    margin:0 0 18px;

    color:#173f5b;

    font-size:28px;

    line-height:1.5;

}

.feature-item__content p{

    margin:0;

    color:#555;

    font-size:16px;

    line-height:2;

}
/*==================================================
  TYPE
==================================================*/

.type-grid{

    display:grid;

    grid-template-columns:repeat(3,1fr);

    gap:30px;

}

.type-card{

    background:#fff;

    border:1px solid #ececec;

    border-radius:20px;

    overflow:hidden;

    transition:.3s;

}

.type-card:hover{

    transform:translateY(-6px);

    box-shadow:0 18px 40px rgba(0,0,0,.08);

}

.type-card img{

    width:100%;

    height:240px;

    object-fit:cover;

    display:block;

}

.type-card__body{

    padding:30px;

}

.type-card h3{

    margin:0 0 18px;

    color:#173f5b;

    font-size:24px;

    line-height:1.5;

}

.type-card p{

    margin:0;

    color:#555;

    line-height:2;

}

.type-card ul{

    margin:24px 0 0;

    padding:0;

    list-style:none;

}

.type-card li{

    padding:10px 0;

    border-top:1px solid #ececec;

    color:#173f5b;

    font-weight:600;

}

/*==================================================
  RECOMMEND
==================================================*/

.recommend-grid{

    display:grid;

    grid-template-columns:repeat(2,1fr);

    gap:30px;

}

.recommend-card{

    background:#fff;

    border:1px solid #ececec;

    border-radius:20px;

    overflow:hidden;

    transition:.3s;

}

.recommend-card:hover{

    transform:translateY(-6px);

    box-shadow:0 18px 40px rgba(0,0,0,.08);

}

.recommend-card img{

    width:100%;

    height:240px;

    object-fit:cover;

    display:block;

}

.recommend-card h3{

    margin:28px 28px 16px;

    color:#173f5b;

    font-size:24px;

}

.recommend-card p{

    margin:0 28px 30px;

    color:#555;

    line-height:2;

}

/*==================================================
  CASE
==================================================*/

.case-grid{

    display:grid;

    grid-template-columns:repeat(2,1fr);

    gap:32px;

}

.case-card{

    background:#fff;

    border:1px solid #ececec;

    border-radius:20px;

    overflow:hidden;

    transition:.3s;

}

.case-card:hover{

    transform:translateY(-6px);

    box-shadow:0 18px 40px rgba(0,0,0,.08);

}

.case-card img{

    width:100%;

    height:300px;

    object-fit:cover;

    display:block;

}

.case-card__body{

    padding:30px;

}

.case-card h3{

    margin:0 0 16px;

    color:#173f5b;

    font-size:24px;

}

.case-card p{

    margin:0;

    color:#555;

    line-height:2;

}
/*==================================================
  FLOW
==================================================*/

.flow-list{

    display:grid;

    grid-template-columns:repeat(5,1fr);

    gap:22px;

}

.flow-item{

    background:#fff;

    border:1px solid #ececec;

    border-radius:18px;

    padding:34px 22px;

    text-align:center;

    transition:.3s;

}

.flow-item:hover{

    transform:translateY(-6px);

    box-shadow:0 18px 40px rgba(0,0,0,.08);

}

.flow-item__number{

    width:68px;

    height:68px;

    margin:0 auto 20px;

    border-radius:50%;

    background:#173f5b;

    color:#fff;

    display:flex;

    align-items:center;

    justify-content:center;

    font-size:24px;

    font-weight:700;

}

.flow-item h3{

    margin:0 0 16px;

    color:#173f5b;

    font-size:20px;

}

.flow-item p{

    margin:0;

    color:#555;

    font-size:15px;

    line-height:2;

}

/*==================================================
  FAQ
==================================================*/

.faq-list{

    max-width:980px;

    margin:0 auto;

}

.faq-item{

    margin-bottom:20px;

    background:#fff;

    border:1px solid #ececec;

    border-radius:16px;

    overflow:hidden;

}

.faq-item summary{

    position:relative;

    padding:24px 70px 24px 28px;

    cursor:pointer;

    list-style:none;

    color:#173f5b;

    font-size:20px;

    font-weight:700;

}

.faq-item summary::-webkit-details-marker{

    display:none;

}

.faq-item summary::after{

    content:"+";

    position:absolute;

    right:28px;

    top:50%;

    transform:translateY(-50%);

    font-size:32px;

}

.faq-item[open] summary::after{

    content:"−";

}

.faq-item div{

    padding:0 28px 28px;

}

.faq-item p{

    margin:0;

    color:#555;

    line-height:2;

}

/*==================================================
  CTA
==================================================*/

.cta-box{

    padding:70px;

    border-radius:20px;

    background:linear-gradient(135deg,#173f5b,#2c6d95);

    color:#fff;

    text-align:center;

}

.cta-box h2{

    margin:0;

    font-size:34px;

    line-height:1.5;

}

.cta-box p{

    max-width:900px;

    margin:28px auto 0;

    line-height:2;

}

.cta-buttons{

    display:flex;

    justify-content:center;

    gap:20px;

    margin-top:40px;

}

.button{

    display:inline-flex;

    justify-content:center;

    align-items:center;

    width:260px;

    height:60px;

    border-radius:999px;

    text-decoration:none;

    font-weight:700;

    transition:.3s;

}

.button--primary{

    background:#fff;

    color:#173f5b;

}

.button--secondary{

    border:2px solid #fff;

    color:#fff;

}

.button:hover{

    transform:translateY(-4px);

}

/*==================================================
  RESPONSIVE
==================================================*/

@media (max-width:1024px){

    .problem-grid{

        grid-template-columns:repeat(2,1fr);

    }

    .type-grid{

        grid-template-columns:1fr;

    }

    .recommend-grid{

        grid-template-columns:1fr;

    }

    .case-grid{

        grid-template-columns:1fr;

    }

    .flow-list{

        grid-template-columns:repeat(2,1fr);

    }

}

@media (max-width:768px){

    .inner{

        width:min(100% - 32px,1180px);

    }

    .whitening-intro .inner,

    .feature-item{

        display:block;

    }

    .problem-grid{

        grid-template-columns:repeat(2,1fr);

        gap:14px;

    }

    .problem-card{

        padding:22px 16px;

    }

    .feature-item{

        padding:24px;

    }

    .feature-item__image{

        margin-bottom:24px;

    }

    .feature-item__image img{

        height:220px;

    }

    .feature-item__content{

        text-align:center;

    }

    .type-card img,

    .recommend-card img,

    .case-card img{

        height:220px;

    }

    .flow-list{

        grid-template-columns:1fr;

    }

    .cta-box{

        padding:45px 24px;

    }

    .cta-box h2{

        font-size:28px;

    }

    .cta-buttons{

        flex-direction:column;

    }

    .button{

        width:100%;

    }

}


/* =========================================================
   WHITENING YOUTUBE
========================================================= */

.whitening-youtube {
    padding: 60px 0;
    background: #fafafa;
}

.whitening-youtube .youtube-thumbnail-modal {
    position: relative;
    width: min(760px, calc(100% - 80px));
    margin: 0 auto;
    overflow: hidden;
}

.youtube-thumbnail-modal__button {
    position: relative;
    display: block;
    width: 100%;
    padding: 0;
    overflow: hidden;
    border: 0;
    background: none;
    cursor: pointer;
}

.youtube-thumbnail-modal__button img {
    display: block;
    width: 100%;
    height: auto;
    aspect-ratio: 16 / 9;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.youtube-thumbnail-modal__button:hover img {
    transform: scale(1.03);
}


/* 再生ボタン */

.youtube-thumbnail-modal__play {
    position: absolute;
    top: 50%;
    left: 50%;
    display: flex;
    width: 76px;
    height: 76px;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.94);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.22);
    transform: translate(-50%, -50%);
    transition:
        transform 0.3s ease,
        background 0.3s ease;
}

.youtube-thumbnail-modal__play span {
    display: block;
    width: 0;
    height: 0;
    margin-left: 5px;
    border-top: 11px solid transparent;
    border-bottom: 11px solid transparent;
    border-left: 17px solid #173f5b;
}

.youtube-thumbnail-modal__button:hover
.youtube-thumbnail-modal__play {
    background: #ffffff;
    transform: translate(-50%, -50%) scale(1.08);
}


/* =========================================================
   MODAL
========================================================= */

.youtube-video-modal {
    position: fixed;
    z-index: 99999;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 30px;
    visibility: hidden;
    opacity: 0;
    pointer-events: none;
    transition:
        opacity 0.3s ease,
        visibility 0.3s ease;
}

.youtube-video-modal.is-open {
    visibility: visible;
    opacity: 1;
    pointer-events: auto;
}

.youtube-video-modal__overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.82);
    cursor: pointer;
}

.youtube-video-modal__content {
    position: relative;
    z-index: 1;
    width: min(1100px, 92vw);
    background: #000;
    box-shadow: 0 25px 80px rgba(0, 0, 0, 0.4);
}

.youtube-video-modal__video {
    width: 100%;
    aspect-ratio: 16 / 9;
}

.youtube-video-modal__video iframe {
    display: block;
    width: 100%;
    height: 100%;
    border: 0;
}

.youtube-video-modal__close {
    position: absolute;
    top: -54px;
    right: 0;
    z-index: 3;
    width: 46px;
    height: 46px;
    padding: 0;
    color: #fff;
    border: 0;
    background: transparent;
    font-size: 40px;
    line-height: 1;
    cursor: pointer;
}


/* =========================================================
   SP
========================================================= */

@media screen and (max-width: 767px) {

    .whitening-youtube {
        padding: 40px 0;
    }

    .whitening-youtube .youtube-thumbnail-modal {
        width: calc(100% - 40px);
    }

    .youtube-thumbnail-modal__play {
        width: 60px;
        height: 60px;
    }

    .youtube-thumbnail-modal__play span {
        border-top-width: 9px;
        border-bottom-width: 9px;
        border-left-width: 14px;
    }

    .youtube-video-modal {
        padding: 15px;
    }

    .youtube-video-modal__content {
        width: 100%;
    }

    .youtube-video-modal__close {
        top: -48px;
        width: 40px;
        height: 40px;
        font-size: 34px;
    }

}