/* ========================================
   Shared Styles - 全ページ共通
   Variables, Container, Header, Mobile Menu,
   Section Base, Footer
   ======================================== */

:root {
  /* Neutral warm palette */
  --t3-bg: #f9f8f6;
  --t3-bg-alt: #f3f2ef;
  --t3-bg-accent: #2c3e50;
  --t3-white: #ffffff;
  --t3-text: #1a1a1a;
  --t3-text-light: #5a5a5a;
  --t3-text-muted: #8a8a8a;
  --t3-accent: #3d5a80;
  --t3-accent-light: #98c1d9;
  --t3-border: rgba(0, 0, 0, 0.08);
}

.t3-container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 40px;
}

/* ========================================
   Header
   ======================================== */
.t3-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 18px 0;
  background: rgba(249, 248, 246, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--t3-border);
}

.t3-header-inner {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 40px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.t3-logo a {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--t3-text);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.t3-logo span {
  color: var(--t3-accent);
}

.t3-nav ul {
  display: flex;
  gap: 36px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.t3-nav a {
  color: var(--t3-text-light);
  text-decoration: none;
  font-size: 0.82rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.t3-nav a.is-current {
  color: var(--t3-accent);
}

.t3-header-btn {
  display: inline-block;
  padding: 10px 24px;
  background: var(--t3-accent);
  color: var(--t3-white);
  text-decoration: none;
  font-size: 0.82rem;
  font-weight: 600;
  border-radius: 3px;
  letter-spacing: 0.02em;
}

/* Hamburger Button */
.t3-hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  padding: 0;
  background: none;
  border: none;
  cursor: pointer;
  z-index: 1001;
}

.t3-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--t3-text);
  margin: 3px 0;
  transition: all 0.3s ease;
}

.t3-hamburger.is-active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.t3-hamburger.is-active span:nth-child(2) {
  opacity: 0;
}

.t3-hamburger.is-active span:nth-child(3) {
  transform: rotate(-45deg) translate(6px, -6px);
}

/* Mobile Menu */
.t3-mobile-menu {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--t3-bg);
  z-index: 999;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}

.t3-mobile-menu.is-open {
  opacity: 1;
  visibility: visible;
}

.t3-mobile-nav ul {
  list-style: none;
  padding: 0;
  margin: 0;
  text-align: center;
}

.t3-mobile-nav li {
  margin: 20px 0;
}

.t3-mobile-nav a {
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--t3-text);
  text-decoration: none;
  letter-spacing: 0.05em;
}

/* ========================================
   Section Base
   ======================================== */
.t3-section {
  padding: 120px 0;
  background: var(--t3-bg);
}

.t3-section-alt {
  background: var(--t3-bg-alt);
}

.t3-section-accent {
  background: var(--t3-bg-accent);
}

.t3-section-accent .t3-section-num,
.t3-section-accent .t3-section-label,
.t3-section-accent .t3-section-title,
.t3-section-accent p {
  color: var(--t3-white);
}

.t3-section-accent .t3-section-label {
  color: var(--t3-accent-light);
}

/* Section Header */
.t3-section-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 16px;
}

.t3-section-header-center {
  justify-content: center;
}

.t3-section-num {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--t3-accent);
  letter-spacing: 0.08em;
}

.t3-section-label {
  font-size: 0.72rem;
  color: var(--t3-text-muted);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-weight: 500;
}

.t3-section-title {
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  font-weight: 700;
  color: var(--t3-text);
  letter-spacing: -0.02em;
  margin-bottom: 24px;
}

.t3-section-title-center {
  text-align: center;
  margin-bottom: 60px;
}

/* ========================================
   Footer
   ======================================== */
.t3-footer {
  background: var(--t3-bg-alt);
  padding: 50px 0 35px;
  border-top: 1px solid var(--t3-border);
}

.t3-footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 30px;
}

.t3-footer-logo {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--t3-text);
}

.t3-footer-logo span {
  color: var(--t3-accent);
}

.t3-footer-nav {
  display: flex;
  gap: 28px;
}

.t3-footer-nav a {
  color: var(--t3-text-light);
  text-decoration: none;
  font-size: 0.78rem;
  letter-spacing: 0.05em;
}

.t3-footer-copy {
  text-align: center;
  padding-top: 25px;
  border-top: 1px solid var(--t3-border);
}

.t3-footer-copy p {
  font-size: 0.72rem;
  color: var(--t3-text-muted);
}

/* ========================================
   Responsive (shared elements)
   ======================================== */
@media (max-width: 1024px) {
  .t3-container {
    padding: 0 30px;
  }

  .t3-header-inner {
    padding: 0 30px;
  }

  .t3-nav {
    display: none;
  }

  .t3-hamburger {
    display: flex;
  }
}

@media (max-width: 768px) {
  .t3-container {
    padding: 0 20px;
  }

  .t3-header-inner {
    padding: 0 20px;
  }

  .t3-header-cta {
    display: none;
  }

  .t3-section {
    padding: 80px 0;
  }

  .t3-footer-inner {
    flex-direction: column;
    gap: 25px;
    text-align: center;
  }

  .t3-footer-nav {
    flex-wrap: wrap;
    justify-content: center;
    gap: 16px;
  }
}