/* 5.8 파트 2 — 앱 톤 동기화: nav 를 랜딩과 동일한 "전폭 투명" 구조로
   logo 좌 / tabs 가운데 (gap 72px) / auth 우 3분할 */
.glass-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    width: 100%;
    max-width: none;
    transform: none;
    border: none;
    border-radius: 0;
    background: transparent;
    backdrop-filter: none;
    box-shadow: none;
    padding: 22px 40px;
    display: flex;
    align-items: center;
    gap: 0;
    z-index: var(--z-nav);
}

.logo {
    flex: 1;
    display: flex;
    justify-content: flex-start;
    font-family: var(--font-title);
    font-size: var(--text-lg);
    font-weight: 800;
    letter-spacing: 0.14em;
    color: var(--color-text-secondary);
    transition: letter-spacing 0.25s ease, color 0.25s ease;
}

/* 로그인 상태 — 닉네임(또는 이메일 short) 표시 시 자간 축소 + 밝은 톤 */
.logo--user {
    letter-spacing: 0.02em;
    font-weight: 700;
    color: var(--color-primary-soft);
    text-shadow: 0 0 10px rgba(140, 230, 216, 0.28);
}

.tabs {
    flex: 2;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 72px;
    margin: 0;
}

.tab-btn {
    border: 0;
    background: transparent;
    border-radius: 0;
    padding: 6px 0;
    color: rgba(236, 255, 255, 0.62);
    font-family: var(--font-body);
    font-size: var(--text-base);
    font-weight: 500;
    letter-spacing: 0.02em;
    text-decoration: none;
    line-height: 1;
    cursor: pointer;
    transition: color 0.2s ease;
}

.tab-btn:hover {
    background: transparent;
    color: #ecffff;
}

.tab-btn:focus-visible {
    outline: 2px solid rgba(62, 201, 199, 0.8);
    outline-offset: 4px;
}

.tab-btn.active {
    background: transparent;
    color: #ecffff;
    font-weight: 700;
}

.tab-btn:disabled,
.tab-btn--disabled {
    cursor: default;
    opacity: 0.45;
}

.tab-btn:disabled:hover,
.tab-btn--disabled:hover {
    background: transparent;
    color: rgba(236, 255, 255, 0.62);
}

.theme-btn {
    min-width: 38px;
    min-height: 34px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.content-area {
    width: 100%;
    height: 100%;
    position: relative;
}

.view {
    position: absolute;
    inset: 0;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.35s ease;
}

.view.active {
    opacity: 1;
    pointer-events: auto;
}

/* ─── Nav Auth 분리 ────────────────────────────────────────────────────────── */

.nav-auth {
    flex: 1;
    display: flex;
    justify-content: flex-end;
    align-items: center;
    gap: 8px;
    margin-left: 0;
    flex-shrink: 0;
}

.nav-auth__login-btn {
    border: 1px solid rgba(114, 229, 215, 0.3);
    background: transparent;
    color: var(--color-text-secondary);
    border-radius: 999px;
    font-family: var(--font-body);
    font-size: var(--text-xs);
    font-weight: 600;
    padding: 6px 14px;
    cursor: pointer;
    transition: color 0.2s, border-color 0.2s, background 0.2s;
    white-space: nowrap;
}

.nav-auth__login-btn:hover {
    color: var(--color-text-bright);
    border-color: rgba(114, 229, 215, 0.6);
    background: rgba(62, 201, 199, 0.1);
}

.nav-auth__user {
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-auth__email {
    display: none;
}

/* Login 버튼과 동일한 테두리 톤으로 통일 */
.nav-auth__logout-btn {
    border: 1px solid rgba(114, 229, 215, 0.3);
    background: transparent;
    color: var(--color-text-secondary);
    border-radius: 999px;
    font-family: var(--font-body);
    font-size: var(--text-xs);
    font-weight: 600;
    padding: 6px 14px;
    cursor: pointer;
    transition: color 0.2s, border-color 0.2s, background 0.2s;
    white-space: nowrap;
}

.nav-auth__logout-btn:hover {
    color: var(--color-text-bright);
    border-color: rgba(114, 229, 215, 0.6);
    background: rgba(62, 201, 199, 0.1);
}

@media (max-width: 768px) {
    .glass-nav {
        padding: 16px 20px;
        gap: 12px;
    }
    .logo {
        flex: 0 0 auto;
    }
    .tabs {
        flex: 1 1 auto;
        gap: 20px;
    }
    .nav-auth {
        flex: 0 0 auto;
    }
    .tab-btn {
        font-size: 12px;
        white-space: nowrap;
    }
    /* 모바일에선 About Us 숨김 — 상단 탭 공간 절약
       (모바일 유저는 랜딩 푸터 또는 /about 직접 접근). 발표 이후 탭 자체 제거 예정. */
    #tab-about,
    #landing-tab-about {
        display: none;
    }
}