body {
  margin: 0;
  padding: 0;
  background: #fafbfc;
  min-height: 100vh;
  font-family: "Segoe UI", "Hiragino Sans", "PingFang SC", Arial, sans-serif;
}

.header {
  background: #fff;
  box-shadow: 0 2px 10px rgba(225,59,43,0.06);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  height: 58px;
  position: sticky;
  top: 0;
  z-index: 99;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1.12em;
  color: #e13b2b;
}
.nav-logo img {
  height: 30px;
  width: 30px;
}
.nav-menu a {
  color: #333;
  text-decoration: none;
  margin-left: 18px;
  font-weight: 500;
  transition: color .18s;
}
.nav-menu a:hover { color: #e13b2b; }

.main-img-wrap {
  width: 100%;
  max-width: 440px;
  margin: 34px auto 0 auto;
  border-radius: 20px;
  background: #fff;
  box-shadow: 0 8px 32px rgba(225,59,43,0.09);
  overflow: hidden;
}
.main-img-wrap img {
  display: block;
  width: 100%;
  height: auto;
}

.main-desc {
  text-align: center;
  max-width: 460px;
  margin: 22px auto 0 auto;
  padding: 0 10px;
}
.main-desc h1 {
  font-size: 1.27em;
  color: #1d2129;
  margin-bottom: 9px;
  font-weight: 700;
}
.main-desc p {
  font-size: 1em;
  color: #3e3e3e;
  margin: 0;
}
.main-desc .highlight {
  color: #e13b2b;
  font-weight: bold;
}

.line-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 94vw;
  max-width: 430px;
  margin: 22px auto 0 auto;
  padding: 15px 0;
  background: #e13b2b;
  color: #fff;
  font-size: 1.18em;
  font-weight: bold;
  border-radius: 16px;
  text-decoration: none;
  box-shadow: 0 8px 32px 0 rgba(225,59,43,0.17), 0 2.5px 8px #e13b2b2b;
  gap: 13px;
  letter-spacing: 1px;
  position: relative;
  transition: 
    transform 0.14s cubic-bezier(.4,0,.2,1), 
    box-shadow 0.19s cubic-bezier(.4,0,.2,1),
    filter 0.22s;
}
.line-btn .line-icon {
  width: 29px;
  height: 29px;
  background: #fff;
  border-radius: 50%;
  padding: 1.5px;
  margin-right: 2px;
  box-shadow: 0 1px 5px rgba(225,59,43,0.13);
}
.line-btn:hover, .line-btn:active {
  transform: translateY(-2px) scale(1.03);
  box-shadow: 0 16px 38px 0 rgba(225,59,43,0.21), 0 3.5px 12px #e13b2b2b;
  filter: brightness(1.03);
}
.mobile-fixed { display: none; }

.footer {
  width: 100%;
  background: #fff;
  border-top: 1px solid #e5e6eb;
  padding: 28px 0 16px 0;
  text-align: center;
  color: #888;
  margin-top: 50px;
  font-size: 0.99em;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.footer small, .footer .footer-copyright {
  display: block;
  text-align: center;
  width: 100%;
}

.footer-copyright {
  margin-top: 10px;
  color: #888;
  font-size: 0.97em;
  letter-spacing: 0.03em;
}

.footer a { color: #e13b2b; text-decoration: none; }
.footer a:hover { text-decoration: underline; }

@media (max-width: 600px) {
  .main-img-wrap { margin: 10px 0 0 0; border-radius: 0; max-width: 100vw; box-shadow: none; }
  .main-desc { margin-top: 18px; }
  .line-btn.pc-only { display: none; }
  .line-btn.mobile-fixed {
    display: flex;
    position: fixed;
    left: 0; right: 0;
    bottom: 28px;
    margin: 0 auto;
    z-index: 50;
    width: 88vw;
    max-width: 410px;
    padding: 14px 0;
    border-radius: 16px;
    box-shadow: 0 24px 56px 0 rgba(225,59,43,0.21), 0 4px 18px #e13b2b42;
    animation: jumpSmooth 1.2s ease-in-out infinite;
    will-change: transform;
  }
  .line-btn.mobile-fixed:active {
    transform: scale(0.96) translateY(5px);
    box-shadow: 0 2px 12px rgba(225,59,43,0.12);
  }
}

@media (max-width: 600px) {
  .main-img-wrap { margin: 10px 0 0 0; border-radius: 0; max-width: 100vw; box-shadow: none; }
  .main-desc { margin-top: 18px; }
  .line-btn.pc-only { display: none; }
  .line-btn.mobile-fixed {
    display: flex;
    position: fixed;
    left: 0; right: 0;
    bottom: 28px;
    margin: 0 auto;
    z-index: 50;
    width: 88vw;
    max-width: 410px;
    padding: 14px 0;
    border-radius: 16px;
    box-shadow: 0 24px 56px 0 rgba(225,59,43,0.21), 0 4px 18px #e13b2b42;
    animation: pulse 1.3s cubic-bezier(0.4,0,0.2,1) infinite;
    will-change: transform;
  }
  .line-btn.mobile-fixed:active {
    transform: scale(0.96);
    box-shadow: 0 2px 12px rgba(225,59,43,0.12);
  }
}

@keyframes pulse {
  0% { transform: scale(1);}
  50% { transform: scale(1.045);}
  100% { transform: scale(1);}
}