/* ヘッダー（PC用のみ） */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--primary-color);
    box-shadow: var(--shadow-md);
    z-index: 1000;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5%;
    max-width: 1400px;
    margin: 0 auto;
}

.logo a {
    font-size: 1.8rem;
    font-weight: 700;
    text-decoration: none;
    color: white;
    transition: opacity 0.3s;
}

.logo a:hover {
    opacity: 0.8;
}

.nav {
    display: flex;
    flex-direction: row;
    align-items: center;
    position: static;
    width: auto;
    max-width: none;
    height: auto;
    background: none;
    box-shadow: none;
    padding-top: 0;
    transform: none !important;
    z-index: 2000;
}

.nav-links {
    display: flex;
    flex-direction: row;
    gap: 2.5rem;
    align-items: center;
    width: auto;
    margin: 0;
    padding: 0;
}

.nav-links li {
    width: auto;
    text-align: left;
}

.nav-links a {
    color: #fff;
    font-size: 1.1rem;
    padding: 0;
    display: block;
    width: auto;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -4px;
    left: 0;
    background: var(--accent-color);
    transition: width 0.3s;
}

.nav-links a:hover::after {
    width: 100%;
}

/* ハンバーガーメニュー初期状態（PC用） */
.hamburger {
  display: none;
}

/* スマホ・タブレット時のみハンバーガー表示、ナビ非表示 */
@media (max-width: 768px) {
  header .header-container .hamburger {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    background: none;
    border: none;
    cursor: pointer;
    z-index: 2200;
    position: relative;
  }
  header .header-container .hamburger span {
    display: block;
    width: 28px;
    height: 3px;
    background: #fff;
    margin: 5px 0;
    border-radius: 2px;
    transition: all 0.3s cubic-bezier(.4,0,.2,1);
  }
  header .header-container .nav {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0;
    right: 0;
    width: 60vw;
    max-width: 260px;
    height: 100vh;
    background: var(--primary-color);
    box-shadow: -2px 0 12px rgba(0,0,0,0.12);
    z-index: 2000;
    align-items: flex-start;
    padding-top: 80px;
    overflow-y: auto;
    transition: transform 0.3s cubic-bezier(.4,0,.2,1), visibility 0.3s, opacity 0.3s;
    transform: translateX(100%);
    visibility: hidden;
    opacity: 0;
    pointer-events: none;
  }
  header .header-container .nav.active {
    transform: translateX(0);
    visibility: visible;
    opacity: 1;
    pointer-events: auto;
  }
  header .header-container .nav-links {
    flex-direction: column;
    gap: 2rem;
    width: 100%;
    margin: 0;
    padding: 0 2rem;
    align-items: flex-start;
  }
}

@media (min-width: 769px) {
  .header .hamburger {
    display: none;
  }
  .header .nav {
    display: flex;
  }
}