.header {
  position: fixed;
  top: 24px;
  width: 100%;
  z-index: 999;
}

.header__inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
}

.header__background {
  width: 80%;
  display: flex;
  justify-content: space-between;
  padding: 16px 80px 16px 48px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
  background: #fff;
  border-radius: 50px;
  align-items: center;
}

.header__logo {
  max-width: 30%;
}

.header__logo img {
  height: 30px;
}

.header__nav {
  max-width: 70%;
}

.header__nav .menu-list {
  display: flex;
  gap: 30px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.header__nav .menu-list li a {
  text-decoration: none;
  color: #333;
}

.header__contact {
  margin-left: 16px;
}

.header__contact a {
  display: inline-block;
  background: #f22f27;
  color: #fff;
  padding: 20px 40px;
  border-radius: 50px;
}

@media screen and (max-width: 1024px) {
  .header__background {
    padding: 16px 40px;
  }
  .header__nav .menu-list li a {
    font-size: 12px;
  }
  .header__nav .menu-list {
    gap: 16px;
  }
  .header__contact a {
    font-size: 14px;
  }
}

@media screen and (max-width: 768px) {
  .header__contact {
    display: none;
  }
  .header__nav {
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: #fff;
    display: none;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    padding: 20px 0;
    z-index: 998;
  }
  .header__nav.active {
    display: flex;
  }
  .header__nav .menu-list {
    flex-direction: column;
    gap: 16px;
  }
  .hamburger {
    display: flex;
  }
  .header__background {
    padding-right: 48px;
    position: relative;
    width: 100%;
  }
}

/* トップへ戻るボタン */

.back-to-top {
  position: fixed;
  bottom: 40px;
  right: 20px;
  z-index: 10;
  cursor: pointer;
  animation: floating-y 1.8s ease-in-out infinite alternate-reverse;
}

.back-to-top img {
  width: 74px;
  height: auto;
}

@keyframes floating-y {
  0% {
    transform: translateY(-10%);
  }
  100% {
    transform: translateY(10%);
  }
}

/* ハンバーガーボタン全体 */

.hamburger {
  display: none;
  /* PCでは非表示 */
  flex-direction: column;
  justify-content: center;
  width: 32px;
  height: 32px;
  gap: 6px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
}

.hamburger__btn {
  display: block;
  width: 28px;
  height: 3px;
  background: #fff;
  /* メニューが青背景なら白が映える */
  transition: 0.3s ease;
}

.hamburger__btn--red {
  background: #e53939;
}

.hamburger__btn--blue {
  background: #125ab2;
}

.hamburger.active .hamburger__btn--red {
  transform: rotate(45deg) translate(7px, 2px);
}

.hamburger.active .hamburger__btn--blue {
  transform: rotate(-45deg) translate(4px, 0px);
}

.header__nav .c-btn {
  display: none;
}

@media screen and (max-width: 768px) {
  .hamburger {
    display: flex;
  }
  .header__logo {
    max-width: 50%;
  }
  .header__nav {
    display: none;
    position: fixed;
    /* ← 開いた時に全画面オーバーレイにする */
    top: 0;
    left: 0;
    width: 100%;
    max-width: 100%;
    height: 100vh;
    /* 画面全体 */
    background: #0056b3;
    /* 背景色（画像の青に近い色に変更） */
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    padding: 100px 20px 40px;
    /* 上部にロゴ、下に余白 */
    z-index: -1;
  }
  .header__nav.active {
    display: flex;
  }
  .header__nav .menu-list {
    flex-direction: column;
    gap: 24px;
    width: 100%;
    margin-top: 16px;
  }
  .header__nav .menu-list li {
    width: 100%;
    border-bottom: 1px solid rgba(255, 255, 255, 0.5);
    padding-bottom: 12px;
  }
  .header__nav .menu-list li a {
    display: flex;
    justify-content: space-between;
    /* テキスト左、矢印右 */
    font-size: 20px;
    font-weight: 700;
    color: #fff;
    text-decoration: none;
  }
  .header__nav .c-btn {
    display: inline-flex;
    gap: 80px;
    padding: 16px 40px;
    font-size: 18px;
  }
}