/* ============================================
   Sophia Academy Ver2 - Header
   透明スタート → スクロールで背景出現
   ============================================ */

.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: var(--sp-lg) 0;
    background: transparent;
    transition: background 0.5s ease, padding 0.4s ease, box-shadow 0.4s ease;
}

/* スクロール後にJSが付与するクラス */
.site-header.scrolled {
    background: rgba(122, 16, 34, 0.97);
    padding: var(--sp-md) 0;
    box-shadow: 0 2px 24px rgba(0, 0, 0, 0.4);
    border-bottom: 1px solid rgba(184, 146, 42, 0.4);
}

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

/* --- Logo --- */
.site-logo {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
    text-decoration: none;
}

.site-logo__img {
    height: 56px;
    width: auto;
    transition: height 0.4s ease;
}

.scrolled .site-logo__img {
    height: 44px;
}

.site-logo__text {
    display: flex;
    flex-direction: column;
}

.site-logo__name {
    font-family: var(--font-en);
    font-size: 1.3rem;
    font-weight: var(--fw-semibold);
    letter-spacing: 0.05em;
    color: var(--color-white);
    line-height: 1;
}

.site-logo__sub {
    font-size: 0.65rem;
    letter-spacing: 0.12em;
    color: var(--color-gold-light);
    margin-top: 2px;
}

/* --- Navigation --- */
.site-nav {
    display: flex;
    align-items: center;
    gap: var(--sp-xl);
}

.site-nav__list {
    display: flex;
    align-items: center;
    gap: var(--sp-md);
    list-style: none;
}

.site-nav__link {
    font-size: var(--fs-sm);
    font-weight: var(--fw-medium);
    color: rgba(255, 255, 255, 0.9);
    letter-spacing: 0.05em;
    padding: var(--sp-xs) var(--sp-sm);
    text-decoration: none;
    position: relative;
    white-space: nowrap;
    transition: color var(--ease-default);
}

.site-nav__link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--color-gold);
    transform: scaleX(0);
    transition: transform var(--ease-luxury);
    transform-origin: right;
}

.site-nav__link:hover {
    opacity: 1;
    color: var(--color-gold-light);
}

.site-nav__link:hover::after {
    transform: scaleX(1);
    transform-origin: left;
}

/* --- CTA Button in Header --- */
.site-nav__cta {
    font-family: var(--font-heading);
    font-size: 0.9rem;
    font-weight: var(--fw-bold);
    padding: 0.65rem 1.4rem;
    background: var(--color-crimson);
    color: var(--color-white);
    border: 1px solid var(--color-crimson-light);
    border-radius: var(--radius-sm);
    white-space: nowrap;
    text-decoration: none;
    transition: all var(--ease-luxury);
    margin-left: var(--sp-md);
}

.site-nav__cta:hover {
    background: var(--color-crimson-dark);
    opacity: 1;
    transform: translateY(-1px);
}

/* Gold line below header content on scroll */
.site-header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(to right, transparent, var(--color-gold), transparent);
    opacity: 0;
    transition: opacity 0.5s ease;
}

.site-header.scrolled::after {
    opacity: 0.5;
}

/* --- Hamburger (SP) --- */
.site-header__hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: var(--sp-xs);
    background: none;
    border: none;
}

.site-header__hamburger span {
    display: block;
    width: 26px;
    height: 2px;
    background: var(--color-white);
    transition: all 0.3s ease;
}

/* --- Mobile Drawer --- */
.site-header__drawer {
    display: none;
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: 280px;
    background: rgba(10, 3, 5, 0.97);
    border-left: 1px solid rgba(184, 146, 42, 0.3);
    z-index: 2000;
    padding: var(--sp-4xl) var(--sp-xl);
    transform: translateX(100%);
    transition: transform 0.4s ease;
    overflow-y: auto;
}

.site-header__drawer.is-open {
    transform: translateX(0);
}

.site-header__drawer-close {
    position: absolute;
    top: var(--sp-md);
    right: var(--sp-md);
    background: none;
    border: none;
    color: var(--color-white);
    font-size: var(--fs-xl);
    cursor: pointer;
}

.site-header__drawer-nav {
    display: flex;
    flex-direction: column;
    gap: 0;
    margin-top: var(--sp-xl);
}

.site-header__drawer-nav a {
    display: block;
    padding: var(--sp-md) 0;
    color: rgba(255, 255, 255, 0.85);
    border-bottom: 1px solid rgba(184, 146, 42, 0.2);
    font-size: var(--fs-md);
    letter-spacing: 0.05em;
    text-decoration: none;
    transition: color var(--ease-default);
}

.site-header__drawer-nav a:hover {
    color: var(--color-gold-light);
}

.site-header__drawer-cta {
    margin-top: var(--sp-xl);
    display: block;
    text-align: center;
    padding: var(--sp-md);
    background: var(--color-crimson);
    color: var(--color-white);
    border-radius: var(--radius-sm);
    font-weight: var(--fw-bold);
    text-decoration: none;
}

@media (max-width: 968px) {
    .site-nav {
        display: none;
    }

    .site-header__hamburger {
        display: flex;
    }

    .site-header__drawer {
        display: block;
    }
}