:root{
  --navy:#26375a;
  --navy-dark:#1c2a45;
  --orange:#e07b3a;
  --gray-text:#4f5954;
  --line-gray:#e0e0e0;
  --blue-bar:#dbe1f0;
  --blue-border:#8ea0d6;
  --blue-link:#2f4aa8;
  --peach-bar:#fae6cb;
  --gray-bar:#d9d9d9;
  --card-bg:#f6f6f6;
  --btn-blue:#7f92c0;
  --btn-blue-dark:#65799f;
  --color-text-mid:#5c5c5c;
  --color-border:#e8e4dc;
}
*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;
  font-family:"Noto Sans JP","Hiragino Kaku Gothic ProN","Hiragino Sans","Yu Gothic",Meiryo,sans-serif;
  color:#222;
  background:#fff;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none;}
img{display:block;max-width:100%;}
.wrap{max-width:1280px;margin:0 auto;padding:0 20px;}
a:focus-visible,button:focus-visible{outline:2px solid var(--orange);outline-offset:3px;border-radius:2px;}

/* ===== site header ===== */
.site-header{
  position:sticky;top:0;z-index:1000;
  background:#fff;border-bottom:1px solid var(--color-border);
  box-shadow:0 2px 8px rgba(0,0,0,.06);
}
.site-header-inner{
  display:flex;align-items:center;justify-content:space-between;
  height:72px;
}
.site-header .logo{display:flex;align-items:center;}
.site-header .logo img{width:130px;height:auto;}
.site-nav ul{display:flex;align-items:center;gap:32px;list-style:none;margin:0;padding:0;}
.site-nav a{
  font-size:14px;color:var(--color-text-mid);font-weight:500;
  padding:4px 0;position:relative;transition:color .22s ease;
}
.site-nav a::after{
  content:"";position:absolute;bottom:-2px;left:0;width:0;height:2px;
  background:var(--orange);transition:width .22s ease;
}
.site-nav a:hover{color:var(--orange);}
.site-nav a:hover::after{width:100%;}

.hamburger{
  display:none;flex-direction:column;gap:5px;
  background:none;border:none;cursor:pointer;padding:4px;
}
.hamburger span{display:block;width:24px;height:2px;background:#2d2d2d;border-radius:2px;transition:transform .22s ease,opacity .22s ease;}
.hamburger.is-active span:nth-child(1){transform:translateY(7px) rotate(45deg);}
.hamburger.is-active span:nth-child(2){opacity:0;}
.hamburger.is-active span:nth-child(3){transform:translateY(-7px) rotate(-45deg);}

.mobile-nav{display:none;background:#fff;border-top:1px solid var(--color-border);padding:8px 20px 16px;}
.mobile-nav ul{display:flex;flex-direction:column;list-style:none;margin:0;padding:0;}
.mobile-nav a{
  display:block;padding:14px 0;font-size:15px;font-weight:500;
  color:var(--color-text-mid);border-bottom:1px solid var(--color-border);
}
.mobile-nav a:hover{color:var(--orange);}
.mobile-nav.is-open{display:block;}

@media (max-width:768px){
  .site-nav{display:none;}
  .hamburger{display:flex;}
}

/* ===== hero ===== */
.hero{padding-top:18px;padding-bottom:26px;}
.hero-inner{display:flex;gap:28px;align-items:stretch;}
.hero-photo{flex:0 0 44%;}
.hero-photo img{width:100%;aspect-ratio:16/9;object-fit:cover;border-radius:6px;}
.hero-content{flex:1 1 auto;padding-top:2px;min-width:0;}
.nasta-logo{margin-bottom:12px;}
.nasta-logo img{height:30px;width:auto;}
.hero-title{
  display:flex;align-items:baseline;gap:10px 14px;flex-wrap:wrap;
  border-bottom:2px solid #222;padding-bottom:12px;margin-bottom:12px;
}
.hero-title .small{font-size:15px;font-weight:bold;color:#222;}
.hero-title .big{font-size:26px;font-weight:900;color:#111;}
.hero-desc{font-size:13.5px;color:var(--gray-text);margin-bottom:18px;line-height:1.8;}
.feature-row{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;}
.feature-item{text-align:left;min-width:0;}
.feature-item img{width:100%;aspect-ratio:11/8;object-fit:cover;border-radius:6px;margin-bottom:8px;}
.feature-item .cap{font-size:11.5px;color:#333;line-height:1.5;}

/* ===== section bars ===== */
.section-bar{
  padding:14px 22px;margin:26px 0 26px;border-radius:2px;
  display:flex;align-items:baseline;gap:18px;flex-wrap:wrap;
}
.section-bar.blue{background:var(--blue-bar);}
.section-bar.peach{background:var(--peach-bar);}
.section-bar.gray{background:var(--gray-bar);}
.section-bar .title{font-size:17px;font-weight:900;white-space:nowrap;}
.section-bar .desc{font-size:13.5px;color:#333;}

.subhead{display:flex;align-items:center;gap:8px;font-size:15px;font-weight:bold;margin:22px 0 18px;color:#222;}
.checkbox{
  width:18px;height:18px;border:2px solid #2f4aa8;border-radius:2px;
  display:flex;align-items:center;justify-content:center;color:#2f4aa8;font-size:12px;font-weight:900;flex:0 0 18px;
}

/* ===== variation panels (バリエーションから選ぶ) ===== */
.variation-panel{
  background:var(--card-bg);border-radius:16px;padding:28px 32px;
  margin-bottom:24px;
  display:grid;
  grid-template-columns:auto 1fr;
  grid-template-areas:
    "photo head"
    "photo casters";
  column-gap:32px;row-gap:16px;
  align-items:center;
}
.variation-panel .v-photo{grid-area:photo;}
.variation-panel .v-photo img{width:170px;object-fit:contain;}
.variation-panel .v-head{grid-area:head;display:flex;align-items:baseline;gap:20px;flex-wrap:wrap;min-width:0;}
.variation-panel .v-title{font-size:19px;font-weight:900;white-space:nowrap;}
.variation-panel .v-desc{font-size:12.5px;color:#666;}
.caster-row{grid-area:casters;display:flex;gap:16px;flex-wrap:wrap;}
.caster-item{
  display:flex;align-items:center;gap:10px;
  background:#fff;border-radius:12px;padding:10px 20px 10px 12px;
  box-shadow:0 1px 4px rgba(0,0,0,.08);
  transition:box-shadow .22s ease,transform .22s ease;
}
.caster-item:hover{box-shadow:0 10px 22px rgba(0,0,0,.14);transform:translateY(-4px);}
.caster-item img{width:44px;height:44px;border-radius:50%;object-fit:cover;flex:0 0 auto;}
.caster-item .label{font-size:14.5px;font-weight:500;text-decoration:underline;color:#222;white-space:nowrap;}

/* ===== product card grid ===== */
.product-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px;margin:8px 0 28px;}
.product-card{
  background:var(--card-bg);border-radius:14px;padding:22px 20px 24px;
  transition:box-shadow .25s ease,transform .25s ease;
}
.product-card:hover{box-shadow:0 10px 24px rgba(0,0,0,.08);transform:translateY(-2px);}
.product-card img{width:100%;aspect-ratio:4/3;object-fit:contain;margin-bottom:16px;}
.product-card .p-title{font-size:17px;font-weight:900;text-decoration:underline;margin-bottom:10px;}
.product-card .p-desc{font-size:12.5px;color:#666;line-height:1.7;margin-bottom:18px;}
.product-card .p-btn{
  display:block;text-align:center;padding:12px 0;border-radius:999px;
  background:var(--btn-blue);color:#fff;font-size:14.5px;font-weight:700;
  box-shadow:0 4px 10px rgba(0,0,0,.10);
  transition:background .2s ease,transform .2s ease,box-shadow .2s ease;
}
.product-card .p-btn:hover{background:var(--btn-blue-dark);transform:translateY(-1px);box-shadow:0 6px 16px rgba(101,121,159,.3);}

.section-top-btn-row{display:flex;justify-content:center;margin:0 0 20px;}
.cta-btn{
  display:inline-block;text-align:center;padding:12px 40px;border-radius:999px;
  background:#e16b1d;color:#fff;font-size:14.5px;font-weight:700;
  box-shadow:0 4px 10px rgba(0,0,0,.10);
  transition:background .2s ease,transform .2s ease,box-shadow .2s ease;
}
.cta-btn:hover{background:#b45617;transform:translateY(-1px);box-shadow:0 6px 16px rgba(225,107,29,.3);}

.see-all{display:block;text-align:center;font-size:15px;font-weight:bold;text-decoration:underline;margin:8px 0 8px;color:#222;}

/* ===== feature cards (特長から選ぶ) ===== */
.feature-cards{display:grid;grid-template-columns:repeat(2,1fr);gap:32px;margin:8px 0 28px;}
.feature-card{
  display:block;background:var(--card-bg);border-radius:16px;padding:26px 28px;
  transition:box-shadow .25s ease,transform .25s ease;cursor:pointer;
}
.feature-card:hover{box-shadow:0 12px 28px rgba(0,0,0,.12);transform:translateY(-4px);}
.feature-card--no-hover:hover{box-shadow:none;transform:none;}
.feature-card .f-title{font-size:17px;font-weight:900;text-decoration:underline;margin-bottom:16px;}
.feature-card .f-photos{display:flex;gap:14px;margin-bottom:16px;}
.feature-card .f-photos img{width:50%;border-radius:8px;object-fit:cover;aspect-ratio:4/3;}
.feature-card .f-desc{font-size:13px;color:#333;line-height:1.9;margin:0;}
.feature-card--wide .f-photos img{width:100%;aspect-ratio:8/3;}

.feature-cards-trio{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:0 0 28px;}
.feature-cards-trio .f-photos img{aspect-ratio:270/197;}

/* ===== size cards (サイズから選ぶ) ===== */
.size-grid{display:flex;gap:24px;flex-wrap:wrap;margin:0 0 30px;}
.size-card{
  flex:1 1 260px;background:var(--card-bg);border-radius:14px;padding:18px 22px;
  display:flex;align-items:center;justify-content:flex-start;gap:16px;
  transition:box-shadow .2s ease,transform .2s ease;
}
.size-card:hover{box-shadow:0 6px 16px rgba(0,0,0,.08);transform:translateY(-2px);}
.size-card img{width:110px;height:90px;object-fit:contain;}
.size-card .label{font-size:16px;font-weight:500;text-decoration:underline;color:#222;white-space:nowrap;}

/* ===== footer ===== */
.site-footer{font-family:inherit;margin-top:50px;}
.footer-nav-area{background:#f0ede8;padding:48px 0 40px;}
.footer-nav-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:40px;}
.footer-nav-group__title{
  font-size:14.5px;font-weight:700;color:#222;
  margin:0 0 18px;padding-bottom:8px;border-bottom:1px solid #d0ccc4;
}
.footer-nav-group__title:not(:first-child){margin-top:24px;}
.footer-nav-group--wide .footer-nav-group__cols{display:grid;grid-template-columns:1fr 1fr;gap:0 20px;}
.footer-nav-list{display:flex;flex-direction:column;gap:10px;list-style:none;margin:0;padding:0;}
.footer-nav-list li{position:relative;padding-left:0;}
.footer-nav-list li::before{content:"› ";color:var(--color-text-mid);font-size:12.8px;}
.footer-nav-list a{font-size:13px;color:var(--color-text-mid);transition:color .2s ease;}
.footer-nav-list a:hover{color:var(--orange);}
.footer-copy-bar{background:#2a2a2a;padding:18px 0;}
.footer-copy{text-align:center;font-size:12.5px;color:#888;margin:0;}

/* ===== back to top ===== */
.back-to-top{
  position:fixed;right:24px;bottom:24px;z-index:900;
  width:52px;height:52px;border-radius:50%;
  background:var(--navy-dark);
  display:flex;align-items:center;justify-content:center;
  box-shadow:0 4px 12px rgba(0,0,0,.25);
  transition:background .2s ease,transform .2s ease,box-shadow .2s ease;
}
.back-to-top:hover{background:var(--navy);transform:translateY(-3px);box-shadow:0 6px 16px rgba(0,0,0,.3);}

@media (max-width:600px){
  .back-to-top{right:16px;bottom:16px;width:44px;height:44px;}
}

@media (max-width:768px){
  .footer-nav-grid{grid-template-columns:1fr 1fr;gap:28px;}
  .footer-nav-group--wide{grid-column:1/-1;}
}
@media (max-width:480px){
  .footer-nav-grid{grid-template-columns:1fr;}
  .footer-nav-group--wide .footer-nav-group__cols{grid-template-columns:1fr;}
}

@media (max-width:900px){
  .hero-inner{flex-wrap:wrap;gap:22px;}
  .hero-photo{flex:1 1 100%;width:100%;}
  .feature-row{grid-template-columns:repeat(2,1fr);}

  .product-grid{grid-template-columns:repeat(2,1fr);}
  .feature-cards-trio{grid-template-columns:repeat(2,1fr);}

  .variation-panel{
    grid-template-columns:auto 1fr;
    grid-template-areas:
      "photo head"
      "casters casters";
    column-gap:14px;row-gap:14px;
    align-items:start;padding:24px;
  }
  .variation-panel .v-head{
    flex-direction:column;align-items:flex-start;gap:6px;
  }
  .variation-panel .v-title{white-space:normal;}
  .variation-panel .v-desc{white-space:normal;}
  .variation-panel .v-photo img{width:120px;}

  .caster-row{
    display:grid;grid-template-columns:repeat(3,1fr);
    gap:8px;margin-top:4px;
  }
  .caster-item{
    flex-direction:column;justify-content:center;text-align:center;
    gap:6px;padding:10px 4px;
  }
  .caster-item img{width:36px;height:36px;margin:0 auto;}
  .caster-item .label{white-space:normal;font-size:12px;line-height:1.3;}
}

@media (max-width:600px){
  .wrap{padding:0 16px;}
  .section-bar{flex-direction:column;align-items:flex-start;gap:6px;}

  .variation-panel .v-photo img{width:100px;}

  .product-grid{grid-template-columns:1fr;}
  .feature-cards{grid-template-columns:1fr;}
  .size-grid{flex-direction:column;}
  .size-card{flex:none;padding:6px 16px;gap:12px;}
}