/* -------------------------------------------------------------------
   Header
------------------------------------------------------------------- */
.header {
    position: fixed; top: 0; left: 0; width: 100%;
    height: var(--header-height);
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    z-index: 1000;
    display: flex; align-items: center;
    transition: var(--transition-fast);
    border-bottom: 1px solid rgba(0,0,0,0.03);
}
.header__container {
    width: 100%; padding: 0 40px;
    display: flex; align-items: center; justify-content: space-between;
    max-width: 1400px; margin: 0 auto;
    position: relative;
}
.header__logo {
    flex-shrink: 0; display: flex; align-items: center;
}
.header__logo img {
    height: 32px; width: auto;
}
.header__nav {
    display: flex; align-items: center;
}
.header__nav-list { display: flex; gap: 40px; }
.header__nav-list a {
    font-size: 13px; font-weight: 500; color: var(--color-text);
    opacity: 0.8; letter-spacing: 0.08em; position: relative; padding: 8px 0;
}
.header__nav-list a::after {
    content: ''; position: absolute; bottom: 0; left: 0;
    width: 0; height: 1px; background: var(--color-accent);
    transition: var(--transition-fast);
}
.header__nav-list a:hover,
.header__nav-list a.is-active { opacity: 1; }
.header__nav-list a:hover::after,
.header__nav-list a.is-active::after { width: 100%; }

.header__contact { display: flex; gap: 12px; flex-shrink: 0; }
.header__contact .btn { padding: 10px 12px 10px 24px; font-size: 12px; }
.header__contact .btn::after { width: 28px; height: 28px; margin-left: 16px; background-size: 12px; }

/* Burger Menu (SP) */
.burger-btn {
    display: none; background: none; border: none; cursor: pointer;
    width: 40px; height: 40px; position: relative; z-index: 1100;
}
.burger-btn span {
    display: block; width: 24px; height: 1px;
    background: var(--color-text); position: absolute; left: 8px;
    transition: var(--transition-fast);
}
.burger-btn span:nth-child(1) { top: 14px; }
.burger-btn span:nth-child(2) { top: 24px; }
.burger-btn.active span:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.burger-btn.active span:nth-child(2) { transform: translateY(-5px) rotate(-45deg); }

.header__nav-sp-contact { display: none; }

/* Desktop: ナビ中央配置 */
@media (min-width: 1025px) {
    .header__nav {
        position: absolute; left: 50%; transform: translateX(-50%);
    }
}

/* 1200px以下: ヘッダーをコンパクトにして重なり防止 */
@media (max-width: 1200px) and (min-width: 1025px) {
    .header__container { padding: 0 24px; }
    .header__nav-list { gap: 24px; }
    .header__nav-list a { font-size: 12px; }
    .header__contact .btn { padding: 8px 10px 8px 18px; font-size: 11px; }
    .header__contact .btn::after { width: 24px; height: 24px; margin-left: 12px; background-size: 10px; }
}

/* Mobile: ハンバーガーメニュー */
@media (max-width: 1024px) {
    .header__nav, .header__contact { display: none; }
    .burger-btn { display: block; }
    .header__container { padding: 0 24px; }

    .header__nav.active {
        display: flex; position: fixed; top: 0; left: 0; width: 100%; height: 100vh;
        background: rgba(255,255,255,0.98); flex-direction: column;
        justify-content: flex-start; align-items: center; z-index: 1050;
        overflow-y: auto; padding-top: 160px;
    }
    .header__nav.active .header__nav-list {
        flex-direction: column; text-align: center; gap: 24px;
    }
    .header__nav.active a { font-size: 18px; }

    .header__nav.active .header__nav-sp-contact {
        display: flex; flex-direction: column; gap: 16px;
        margin-top: 32px; width: 80%; max-width: 300px;
    }
    .header__nav-sp-contact .btn { width: 100%; }
}