/* 頁首與導覽列元件 */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: var(--color-white);
    box-shadow: var(--shadow-sm);
    border-bottom: 3px solid var(--color-primary);
}

.site-header__inner {
    height: var(--header-height);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-md);
}

/* Logo */
.site-logo {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    font-weight: 900;
}

.site-logo__mark {
    width: auto;
    height: 4rem;
    max-width: 16.2rem;
    object-fit: contain;
}

.site-header .site-logo__text {
    display: none;
}

.site-logo__text {
    font-family: var(--font-logo);
    font-size: var(--fs-lg);
    font-weight: 900;
    color: var(--color-primary);
    letter-spacing: 0.06em;
    line-height: 1.1;
}

.site-logo__text--light {
    color: var(--color-white);
}

/* 桌面導覽列上方快捷圖示 */
@media (min-width: 1025px) {
    .site-header .site-nav.site-nav--with-topicon,
    .site-header .site-nav:has(.topicon.area) {
        display: flex;
        flex-direction: column;
        align-items: stretch;
        flex: 1 1 auto;
        min-width: 0;
        margin-right: var(--space-sm);
        gap: 0.2rem;
    }

    .site-header .site-nav__list {
        flex: 0 0 auto;
        width: 100%;
        min-width: 0;
        justify-content: flex-end;
        gap: 2rem;
    }

    .topicon.area {
        display: flex;
        flex-direction: row;
        align-items: center;
        justify-content: flex-end;
        gap: 0.35rem;
        width: 100%;
        padding-bottom: 0.1rem;
    }

    .topicon__link {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 2rem;
        height: 2rem;
        line-height: 0;
        transition: opacity var(--transition);
    }

    .topicon__link:hover {
        opacity: 0.82;
    }

    .topicon__icon {
        width: 1.625rem;
        height: 1.625rem;
        object-fit: contain;
        display: block;
    }

    .topicon__icon--star {
        padding: 1px 0;
        box-sizing: border-box;
    }
}

@media (max-width: 1024px) {
    .topicon.area {
        display: none;
    }
}

/* 桌面導覽 */
.site-nav__list {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 2rem;
}

.site-nav__link {
    font-size: var(--fs-base);
    font-weight: 500;
    color: var(--color-text);
    padding: 0.4rem 0;
    position: relative;
}

.site-nav__link::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -2px;
    width: 0;
    height: 2px;
    background: var(--color-primary);
    transition: width var(--transition);
}

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

.site-nav__link.is-active::after {
    width: 0;
}

.site-nav__link.is-active {
    color: var(--color-primary);
    font-weight: 700;
}

/* 漢堡按鈕（桌面隱藏） */
.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 2.75rem;
    height: 2.75rem;
    background: transparent;
    border: none;
    cursor: pointer;
}

.nav-toggle__bar {
    display: block;
    width: 1.6rem;
    height: 2px;
    background: var(--color-primary);
    transition: transform var(--transition), opacity var(--transition);
}

.nav-toggle.is-open .nav-toggle__bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}
.nav-toggle.is-open .nav-toggle__bar:nth-child(2) {
    opacity: 0;
}
.nav-toggle.is-open .nav-toggle__bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* 手機側拉選單 */
.mobile-nav {
    position: fixed;
    top: 0;
    right: 0;
    width: 78%;
    max-width: 320px;
    height: 100vh;
    background: var(--color-white);
    box-shadow: var(--shadow-lg);
    padding: calc(var(--header-height) + var(--space-md)) var(--space-lg) var(--space-lg);
    transform: translateX(100%);
    transition: transform var(--transition);
    z-index: 99;
    overflow-y: auto;
}

.mobile-nav.is-open {
    transform: translateX(0);
}

.mobile-nav__list li {
    border-bottom: 1px solid var(--color-border);
}

.mobile-nav__link {
    display: block;
    padding: var(--space-md) 0;
    font-size: var(--fs-md);
    font-weight: 500;
}

.mobile-nav__link.is-active {
    color: var(--color-primary);
    font-weight: 100;
}

.mobile-nav__overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.45);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition);
    z-index: 98;
}

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

/* 響應式：平板以下收合桌面選單、顯示漢堡 */
@media (max-width: 1024px) {
    .site-nav,
    .site-header__cta {
        display: none;
    }
    .nav-toggle {
        display: flex;
    }

    .site-header .site-header__inner {
        height: auto;
        min-height: 3.15rem;
        padding: var(--space-xs) 0;
    }

    .site-header .site-logo__mark {
        height: 3.375rem;
        max-width: 11.7rem;
    }
}

@media (max-width: 767px) {
    .site-header .site-header__inner {
        min-height: 2.925rem;
        padding: 0;
    }

    .site-header .site-logo__mark {
        height: 2.5875rem;
        max-width: 9.45rem;
    }

    .nav-toggle {
        width: 2.5rem;
        height: 2.5rem;
    }
}