/* =========================================
   HEADER (sticky)
   ========================================= */

.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(254, 253, 251, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--line);
    padding: 0 var(--space-md);
    transition: box-shadow 0.2s ease;
}

.site-header.is-scrolled {
    box-shadow: 0 4px 20px rgba(43, 58, 47, 0.06);
}

.site-header__inner {
    max-width: var(--container-wide);
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
    padding: 0 var(--space-md);
}

.site-header__logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.site-header__logo-img {
    height: 40px;
    width: auto;
}

/* --- Desktop Nav: デフォルト非表示、md以上で表示 --- */
.site-nav {
    display: none;
    align-items: center;
    gap: var(--space-lg);
}

.site-nav__link {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-main);
    transition: color var(--duration-fast);
    position: relative;
}

.site-nav__link:hover {
    color: var(--gold-dark);
}

.site-nav__link::after {
    content: "";
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gold);
    transition: width 0.2s ease;
}

.site-nav__link:hover::after {
    width: 100%;
}

.site-nav__cta-wrap {
    display: flex;
    gap: 8px;
    align-items: center;
}

.site-nav__cta {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: var(--deep);
    color: #fff;
    padding: 8px 16px;
    border-radius: var(--radius-pill);
    font-size: 13px;
    font-weight: 700;
    transition: all var(--duration-fast) ease;
}

.site-nav__cta:hover {
    background: var(--deep-light);
    transform: translateY(-1px);
}

.site-nav__cta--line {
    background: #06C755;
}

.site-nav__cta--line:hover {
    background: #05b04c;
}

/* --- Mobile Toggle: デフォルト表示、md以上で非表示 --- */
.site-header__toggle {
    display: block;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.site-header__toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--ink);
    margin: 5px 0;
    transition: all var(--duration-fast) ease;
}

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

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

.site-header__toggle.is-active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* --- Mobile Nav Overlay --- */
.mobile-nav {
    display: none;
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(254, 253, 251, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    z-index: 99;
    padding: var(--space-xl) var(--space-lg);
}

.mobile-nav.is-open {
    display: block;
}

.mobile-nav__link {
    display: block;
    padding: var(--space-md) 0;
    font-size: 18px;
    font-weight: 600;
    color: var(--text-main);
    border-bottom: 1px solid var(--line);
}

.mobile-nav__cta {
    display: block;
    text-align: center;
    background: var(--deep);
    color: #fff;
    padding: 14px;
    border-radius: var(--radius-pill);
    font-size: 18px;
    font-weight: 700;
    margin-top: var(--space-lg);
}


/* =========================================
   md — タブレット以上でデスクトップナビ表示
   ========================================= */

@media (min-width: 768px) {
    .site-header__inner {
        padding: 0 var(--space-sm);
    }

    .site-header__logo-img {
        height: 40px;
    }

    .site-nav {
        display: flex;
        gap: var(--space-md);
    }

    .site-nav__link {
        font-size: 13px;
        white-space: nowrap;
    }

    .site-nav__cta {
        padding: 6px 12px;
        font-size: 12px;
        white-space: nowrap;
    }

    .site-header__toggle {
        display: none;
    }
}

@media (min-width: 1024px) {
    .site-header__inner {
        padding: 0 var(--space-xl);
    }

    .site-header__logo-img {
        height: 48px;
    }

    .site-nav {
        gap: var(--space-lg);
    }

    .site-nav__link {
        font-size: 15px;
    }

    .site-nav__cta {
        padding: 8px 16px;
        font-size: 13px;
    }
}