/* --- Variables & Reset --- */
:root {
  --primary-color: #2563eb;
  --secondary-color: #64748b;
  --dark-color: #1e293b;
  --light-color: #f8fafc;
  --white: #ffffff;
  --accent-color: #f59e0b;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  height: 100%;
}

body {
  font-family:
    "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans",
    Meiryo, sans-serif;
  line-height: 1.6;
  color: var(--dark-color);
  background-color: var(--white);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

main {
  flex: 1;
  padding-bottom: 80px;
}

img {
  max-width: 100%;
  vertical-align: bottom;
}

a {
  text-decoration: none;
  color: inherit;
  transition: 0.3s;
}

/* --- Layout Helpers --- */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

.section-title {
  text-align: center;
  font-size: 2rem;
  margin-bottom: 3rem;
  position: relative;
}

.section-title::after {
  content: "";
  display: block;
  width: 50px;
  height: 3px;
  background: var(--primary-color);
  margin: 10px auto 0;
}

.section-text span {
  display: inline-block;
}

/* --- Components: Button --- */
.btn {
  display: inline-block;
  padding: 15px 40px;
  background: var(--accent-color);
  color: var(--white);
  border-radius: 30px;
  font-weight: bold;
  cursor: pointer;
}

.btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 5px 15px rgba(245, 158, 11, 0.4);
}

/* --- Layout: Header --- */
.header {
  background: var(--white);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 80px;
  padding: 0 40px;
}

.logo {
  font-size: 1.5rem;
  font-weight: bold;
  color: var(--primary-color);
}

.nav-list {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-list a:hover {
  color: var(--primary-color);
}

/* --- Layout: Page Header--- */
.lower-page-header {
  background-color: var(--dark-color);
  background: linear-gradient(135deg, #1e293b 0%, #334155 100%);
  color: var(--white);
  padding: 120px 0 80px;
  text-align: center;
}

.lower-page-header h1 {
  font-size: 3.5rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 15px;
  position: relative;
  display: inline-block;
}

.lower-page-header h1::after {
  content: "";
  display: block;
  width: 40px;
  height: 4px;
  background: var(--primary-color);
  margin: 10px auto 0;
}

.lower-page-header p {
  font-size: 1.1rem;
  opacity: 0.8;
  max-width: 600px;
  margin: 0 auto;
}

/* --- Layout: Footer --- */
.footer {
  background: var(--dark-color);
  color: var(--white);
  padding: 60px 0 20px;
  margin-top: auto;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 40px;
}

.logo-footer {
  font-size: 1.8rem;
  margin-bottom: 10px;
}

.footer-info p {
  opacity: 0.7;
  font-size: 0.9rem;
}

.footer-nav-list {
  display: flex;
  list-style: none;
  gap: 1.5rem;
}

.footer-nav-list a:hover {
  color: var(--accent-color);
}

.footer-bottom {
  text-align: center;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 20px;
  font-size: 0.8rem;
  opacity: 0.6;
}

/* --- Responsive for Common Parts --- */
@media (max-width: 768px) {
  .lower-page-header {
    padding: 60px 0;
  }

  .lower-page-header h1 {
    font-size: 2.5rem;
  }

  .header-inner {
    flex-direction: column;
    height: auto;
    padding: 20px;
  }

  .footer-inner {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 30px;
  }

  .footer-nav-list {
    flex-direction: column;
    gap: 10px;
  }

  .nav {
    margin-top: 20px;
  }

  .nav-list {
    gap: 1rem;
  }

  .section-text {
    font-size: 0.95rem;
    line-height: 1.8;
    padding: 0 15px;
  }

  .section-text br {
    display: none;
  }
}