body {
    margin: 0;
    font-family: sans-serif;
}

/* 固定ヘッダー */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 80px;
    /* background-color: #00271C; */
    background-color: rgba(0, 39, 28, 0.9);
    backdrop-filter: blur(8px); /* 背景ぼかし効果（対応ブラウザのみ） */
    color: white;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    box-sizing: border-box;
    z-index: 1000;
}
.header-left {
    flex: 0 0 auto;
    font-size: 20px;
    font-weight: bold;
}
.header-center {
    flex: 1 1 auto;
    display: flex;
    justify-content: center;
    gap: 30px; /* メニューの間隔 */
}
.header-center a {
    color: white;
    text-decoration: none;
    font-size: 1vw;
    font-weight: 500;
}
.header-right {
    flex: 0 0 auto;
}
.custom-btn {
  width: 180px;
  height: 40px;
  background-color: transparent;      /* 背景透明 */
  border: 2px solid #5AE5C3; 
  border-radius: 8px;
  color: #5AE5C3;
  font-weight: bold;
  letter-spacing: 2px;               /* 文字の間隔 */
  cursor: pointer;
  display: flex;
  align-items: center;                /* 縦中央 */
  justify-content: center;            /* 横中央 */
  font-size: 16px;                    /* 文字サイズ調整可 */
  transition: 0.3s;                   /* ホバー用 */
}
.custom-btn:hover {
  background-color: #5AE5C3;          /* ホバーで背景を塗る場合 */
  color: #00271C;                     /* 文字色を変える場合 */
}

/* コンテンツ部分 */
main {
    display: block;
}
.top {
    /* border: 1px solid #ff0000; */
    background-color: #003125;
    position: relative;
    overflow: hidden;
}
.bg-video {
    width: 100%;
    height: auto;
    display: block;
}
.top_msg {
    /* border: 1px solid #ff0000; */
    position: absolute;
    top:25%;
    left: 5%;
    height: calc(550/880 * 100%);
    display: flex;
    flex-direction: column;           /* 縦に並べる */
    align-items: center;              /* 横中央揃え */
    text-align: center;               /* 複数行の文字も中央 */
}
.top_msg1 {
    color: #E5F1FF;
    font-size: 3vw;
    font-weight: bold;
}
.top_msg2 {
    color: #E5F1FF;
    font-size: 1vm;
    font-weight: bolder;
}

.top_btn {
    position: absolute;
    bottom:0;
    left: 50%;
    transform: translateX(-50%);
    width: calc(500 / 720 * 100%);   /* 横幅比例 */
    height: calc(76 / 550 * 100%);   /* 高さも横幅に合わせて比例 */
    background-color: #5AE5C3;
    border-radius: 8px;
    display: flex;
    justify-content: center;  /* 横中央 */
    align-items: center;      /* 縦中央 */
    font-size: calc(20 / 1920 * 100vw); /* フォントサイズ比例 */
    color: #1A2350;
    font-weight: bold;
    text-align: center;
    cursor: pointer;
    user-select: none;
}
.top_img {
    /* border: 1px solid #ff0000; */
    position: absolute;
    display: flex;
    top: calc(50% + 40px);
    right: 5vw;
    transform: translateY(-50%);
    width: calc((402 + 307 + 14) / 1920 * 100vw);   /* 横幅比例 */
}

.top_img1 {
    /* border: 1px solid #ff0000; */
    width: calc(402 / (402 + 307 + 14) * 100%);   /* 横幅比例 */
    height: auto;
    margin-right: calc(14 / (402 + 307 + 14) * 100%);
    flex-shrink: 0;
}
.top_img2 {
    width: calc(307 / (402 + 307 + 14) * 100%);   /* 横幅比例 */
    height: auto;
    flex-shrink: 0;
}

/* 実績部分 */
.act {
    width: 100%;
    height: 200px;
    position: relative;
    box-shadow: 0 4px 6px rgba(0,0,0,0.2);
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #F9FAFB;
}
.act::after {
    content: "※弊社集計による";
    position: absolute;
    bottom: 5px;
    right: 10px;
    font-size: 12px;
    color: #666;
}

.act_par {
    position: absolute;
    width: calc(1200 / 1920 * 100vw);
    display: flex;
    justify-content: space-between; /* 子要素等間隔 */
    align-items: center;            /* 縦中央 */
}
.act_chd1,.act_chd2, .act_chd3, .act_chd4 {
    /* border: 1px solid #ff0000; */
    width: 25%;
    display: flex;
    flex-direction: column;      /* 縦並び */
    justify-content: center;
    align-items: center;
}
.act_chd1 img, .act_chd2 img, .act_chd3 img, .act_chd4 img { 
    max-width: 60px;
    height: auto;
    margin-bottom: 0;
}
.act_chd1 h3, .act_chd2 h3, .act_chd3 h3, .act_chd4 h3 {
    font-weight: bold;
    font-size: 26px;
    margin: 2px 0;
}
.act_chd1 p, .act_chd2 p, .act_chd3 p, .act_chd4 p {
    font-size: 1vw;
    margin: 0;
    color: #666;
}


.introduction1-1 {
    display: block;                        /* ブロック扱いで中央配置 */
    margin: 100px auto 0 auto;
    width: calc(1476 / 1920 * 100%);
    max-width: 100%;
    height: auto;
}
.introduction1-2 {
    display: block;                        /* ブロック扱いで中央配置 */
    margin: 80px auto 0 auto;
    width: calc(1476 / 1920 * 100%);
    max-width: 100%;
    height: auto;
}

.background-container {
  width: 100%;
  position: relative;
}
.introduction2 {
  margin-top: 100px;
}
.introduction3 {
  margin-top: 0;
}
.introduction-b {
  top: 0;
  left: 0;
  width: 100%;
  height: auto;
}

.introduction4-1 {
    display: block;                        /* ブロック扱いで中央配置 */
    margin: 100px auto 0 auto;
    width: calc(873 / 1920 * 100%);
    max-width: 100%;
    height: auto;
}
.introduction4-2 {
    /* border: 1px solid #ff0000; */
    display: block;                        /* ブロック扱いで中央配置 */
    margin: 100px auto 0 auto;
    /* width: calc(1310 / 1920 * 100%); */
    width: 1270px;
    display: flex;
    justify-content: space-between; /* 子要素等間隔 */
    align-items: center;            /* 縦中央 */
}
.introduction4-2 .ex{
    position: relative;
    width: 28%;
    display: flex;
    align-items: center;
    cursor: pointer;
}

.introduction4-2 .base{
    width: 350px;
    height: 557px!important;
    box-sizing: border-box; /* パディングがあってもサイズが崩れない */
    border-radius: 10px;
    border: 1px solid #707070;
    background-color: #ffffff;
    overflow: hidden; /* 角丸内でのはみ出し防止 */
    margin: 0 25px;
    padding: 0;
    display: flex;
    flex-direction: column;
    /* justify-content: center; */
    align-items: center;
    justify-content: flex-start;
    cursor: pointer;
}
.introduction4-2 img{
    width: 100%!important;
    height: auto!important;
    border-radius: 0!important;
    box-shadow: none !important;
}
.introduction4-2 .logo{
    margin: 0 auto;
    width: 312px!important;
    height: 138px!important;
    border-radius: 0!important;
    box-shadow: none !important;
    border-bottom: 1px solid #707070;
    /* border: 1px solid #ff0000; */

    display: flex!important;
    justify-content: center!important; /* 横方向中央 */
    align-items: center!important;     /* 縦方向中央 */
    position: relative!important;      /* 必要に応じて */
}
.introduction4-2 .logo img {
  width: auto!important;
  height: auto!important;
  max-width: 100%!important;
  max-height: 100%!important;
}
.introduction4-2 .msg{
    /* border: 1px solid #ff0000; */
    display: flex!important;
    font-weight: 300;
    font-size: 18px;
    margin: 20px auto;
    width: 290px!important;
    height: 68px!important;
    border-radius: 0!important;
    box-shadow: none !important;
    display: flex!important;
    justify-content: center!important; /* 横方向中央 */
    position: relative!important;      /* 必要に応じて */
    line-height: 1.6!important;

}
.introduction4-2 .btn {
    background-color: #EB6E1E;
    padding: 8px;
    width: 163px;
    height: 26px;
    border-radius: 8px;
    font-weight: bold;
    font-size: 1vw;
    display: flex!important;
    justify-content: center!important;
    align-items: center;
    text-align: center;
    cursor: pointer;
    margin: 0 auto;
}

.introduction4-2 .btn::after {
  content: "▷ 詳しく見る";
  color: #fff;
  display: inline-block;
}
.introduction4-2 .btn:hover {
  background-color: #bbb;
}
.notic1 {
    display: block;                        /* ブロック扱いで中央配置 */
    margin: 100px auto 0 auto;
    width: calc(180 / 1920 * 100%);
    max-width: 100%;
    height: auto;
}
.notic2 {
  width: calc(1000 / 1920 * 100vw);
  margin: 60px auto 100px auto;
}
.notice-box {
  display: flex;
  align-items: center;
  border-top: 1px dotted #515151;
  padding: 10px 0;
}
.notice-box.bottom-line {
  border-bottom: 1px dotted #515151;
}
.notice-date {
  font-size: 18px;
  padding-left: 18px;
  flex-shrink: 0;
}

.notice-content {
  padding-left: 50px;
  font-size: 18px;
}

.notice-content a {
  font-weight: bold;
  color: #37545E;
  text-decoration: none;
}
.notice-content a:hover {
  text-decoration: underline;
}
.notice-content {
  font-weight: bold;
  color: #37545E;
}

.c-link {
  margin-left:60px;
  cursor: pointer;
  font-size: 12px;
  color: #202020;
}

.footer {
  width: 100%;
  height: 80px;
  background-color: #00271C;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  position: relative;
  bottom: 0;
}

.footer-content {
    /* border: 1px solid #ff0000; */
  text-align: center;
  height: 100%;
}

.footer-logo {
  margin: 6px auto 0 auto;
  height: 28px;
  width: auto;
}

.footer-copy {
  color: #ffffff;
  font-size: 12px;
  margin: 1px;
}



.ab { position: absolute; }
.left { justify-content: flex-start; }
.center { justify-content: center; }
.right { justify-content: flex-end; }


/* 下から上に登るフェードイン用 */
.fade-up {
  opacity: 0;
  transform: translateY(50px);
  transition: all 0.8s ease-out;
}
.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* スクロールアップ */
.scroll-top {
  position: fixed;
  bottom: 10px;
  right: 20px;
  width: 48px;
  height: 48px;
  background: none;
  border: none;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
  z-index: 1000;
}

.scroll-top img {
  width: 100%;
  height: 100%;
}

.scroll-top.visible {
  opacity: 1;
  pointer-events: auto;
}

#case-studies {
  scroll-margin-top: 100px; /* 固定ヘッダーの高さなどに合わせて調整 */
}