/* Left Panel */
.left-panel {
    position: fixed;
    left: 0;
    top: 0;
    width: var(--left-width);
    /* 100vh fallback, 100dvh 는 iOS Safari 주소창 펼침/접힘 시 자동 보정 */
    height: 100vh;
    height: 100dvh;
    background: var(--left-bg);
    border-right: 1px solid var(--left-border);
    display: flex;
    flex-direction: column;
    padding: 1rem;
    z-index: 20;
    transform: translateX(-100%);
    transition: transform var(--transition);
}

.left-panel.active {
    transform: translateX(0);
}

@media (min-width: 768px) {
    .left-panel {
        transform: translateX(0);
    }
}

.left-header {
    display: flex;
    align-items: center;
    justify-content: center;       /* 로고 가운데 정렬 (close btn 은 absolute 로 분리) */
    position: relative;
    padding-bottom: 1rem;
    margin-bottom: 0.5rem;
    height: 3rem;
}

.logo-text {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text);
    text-decoration: none;
    letter-spacing: -0.025em;
    text-align: center;
    flex: 1;
}

.logo-text:hover {
    text-decoration: none;
    color: var(--color-text);
}

.close-left-panel {
    display: none;
    align-items: center;
    justify-content: center;
    width: 2rem;
    height: 2rem;
    background: transparent;
    border: none;
    font-size: 1.25rem;
    color: var(--color-text-muted);
    cursor: pointer;
    border-radius: 0.375rem;
    transition: all var(--transition);
    /* 로고를 가운데로 보내기 위해 close btn 은 absolute 로 빼냄 (모바일에서만 보임) */
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
}

.close-left-panel:hover {
    background: var(--left-hover);
    color: var(--color-text);
}

@media (max-width: 767px) {
    .close-left-panel {
        display: flex;
    }
}

/* Tabs (Chat / Studio) */
.left-tabs {
    display: flex;
    gap: 0.25rem;
    padding: 0.25rem;
    margin-bottom: 1rem;
    background: var(--color-bg-tertiary, #f1f5f9);
    border-radius: 0.375rem;
    flex-shrink: 0;
}

.left-tab {
    flex: 1;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    appearance: none;
    border: none;
    background: transparent;
    color: var(--color-text-muted);
    font-size: 0.8125rem;
    font-weight: 500;
    line-height: 1.25;
    padding: 0.375rem 0.75rem;
    border-radius: 0.375rem;
    cursor: pointer;
    transition: all var(--transition);
    font-family: inherit;
    text-align: center;
    text-decoration: none;
}

.left-tab:hover {
    color: var(--color-text);
    text-decoration: none;
}

.left-tab.active {
    background: var(--color-bg, #ffffff);
    color: var(--color-text);
    font-weight: 600;
    box-shadow: 0 1px 2px rgba(15, 23, 42, 0.08);
}

/* Menu */
.menu-list {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.125rem;
    overflow-y: auto;
    min-height: 0;
}

/* Tab panes — only the active pane is visible */
.left-tab-pane {
    display: none;
    flex-direction: column;
    gap: 0.125rem;
}

.menu-list[data-active="chat"] .left-tab-pane[data-pane="chat"],
.menu-list[data-active="studio"] .left-tab-pane[data-pane="studio"],
.menu-list[data-active="account"] .left-tab-pane[data-pane="account"],
.menu-list[data-active="settings"] .left-tab-pane[data-pane="settings"],
.menu-list[data-active="admin"] .left-tab-pane[data-pane="admin"] {
    display: flex;
}

/* nav-item-logout — 사이드바 계정 탭의 로그아웃 button (button 기본값 리셋 + 빨간 hover) */
.nav-item-logout {
    appearance: none;
    background: transparent;
    border: 0;
    cursor: pointer;
    text-align: left;
    font: inherit;
    width: 100%;
}
.nav-item-logout:hover {
    color: #ef4444;
}
.nav-item-logout:hover svg {
    color: #ef4444;
}


.nav-item {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    padding: 0.375rem 0.75rem;
    border-radius: 0.375rem;
    color: var(--color-text-secondary);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all var(--transition);
    flex-shrink: 0;
}

.nav-item:hover {
    background: var(--left-hover);
    color: var(--color-text);
    text-decoration: none;
}

.nav-item.active {
    background: var(--slate-800);
    color: white;
}

.nav-item.active:hover {
    background: var(--slate-700);
}

.nav-item svg {
    flex-shrink: 0;
    width: 1.125rem;
    height: 1.125rem;
    color: var(--color-text-secondary);
    transition: color var(--transition);
}

.nav-item:hover svg { color: var(--color-text); }
.nav-item.active svg { color: white; }

/* Sub-menu tree */
.nav-group {
    display: flex;
    flex-direction: column;
}

.nav-children {
    display: none;
    flex-direction: column;
    padding-left: 1rem;
    gap: 0.125rem;
}

.nav-group.expanded > .nav-children {
    display: flex;
}

.nav-arrow {
    margin-left: auto;
    font-size: 0.7rem;
    color: var(--color-text-muted);
    flex-shrink: 0;
    cursor: pointer;
    padding: 0.1rem 0.4rem;
    border-radius: 3px;
    transition: all var(--transition);
}

.nav-arrow:hover {
    color: var(--color-text);
    background: var(--left-hover);
}

.nav-child {
    padding-left: 0.5rem;
}

/* New Chat */
.nav-new-chat {
    color: var(--color-primary);
    font-weight: 600;
}

.nav-new-chat svg {
    color: var(--color-primary);
}

.nav-new-chat:not(.active):hover {
    background: var(--color-bg-tertiary);
    color: var(--color-primary-hover);
}

.nav-new-chat:not(.active):hover svg {
    color: var(--color-primary-hover);
}

/* Separator */
.nav-separator {
    border-top: 1px solid var(--color-border);
    margin: 0.875rem 0;
}

/* Section title */
.nav-section-title {
    font-size: 0.6875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
    padding: 0.5rem 0.75rem 0.25rem;
    flex-shrink: 0;
}

/* 두 section (favorites → recent) 사이 시각 분리 — chat-list 다음에 오는
   section-title 은 위쪽 간격을 더 주고 살짝의 디바이더 라인으로 그룹 경계 강조.
   다만 즐겨찾기가 0개여서 chatSectionSeparator 가 이미 그룹 경계 라인을 그리는
   경우엔 라인이 두 개 가까이 붙어 보이는 중복 문제가 생기므로, left.js 가
   recentChatsTitle 에 `.no-fav-divider` 를 달 때 이 룰을 끈다. */
.chat-list + .nav-section-title {
    margin-top: 0.625rem;
    padding-top: 0.75rem;
    border-top: 1px solid var(--color-border, #e2e8f0);
}
.chat-list + .nav-section-title.no-fav-divider {
    border-top: none;
    padding-top: 0;
    margin-top: 0;
}

.nav-section-title-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
}

.nav-section-action {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    font-size: 0.6875rem;
    font-weight: 600;
    text-transform: none;
    letter-spacing: 0;
    /* 사용자 눈에 띄게 — 더 진한 슬레이트 + 살짝 underline */
    color: var(--slate-700);
    text-decoration: underline;
    text-decoration-color: var(--slate-300);
    text-underline-offset: 2px;
    transition: color var(--transition), text-decoration-color var(--transition);
}

.nav-section-action:hover {
    color: var(--color-primary);
    text-decoration-color: var(--slate-500);
    text-decoration: underline;
    text-underline-offset: 2px;
}

/* Chat list */
.chat-list {
    display: flex;
    flex-direction: column;
    gap: 0.125rem;
}

.chat-list-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.375rem 0.75rem;
    border-radius: 0.375rem;
    color: var(--color-text-secondary);
    text-decoration: none;
    font-size: 0.8125rem;
    transition: all var(--transition);
    cursor: pointer;
}

.chat-list-item:hover {
    background: var(--left-hover);
    color: var(--color-text);
    text-decoration: none;
}

.chat-list-item.active {
    background: var(--left-active);
    color: var(--color-text);
}

.chat-list-title {
    flex: 1;
    min-width: 0;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* 익명 사용자에게 보이는 sample chat — 실제 데이터 없음 표시용 살짝 dim */
.chat-list-item-sample { opacity: 0.78; }
.chat-list-item-sample:hover { opacity: 1; }

/* 진행 중 채팅 — 항목 좌측에 작은 펄스 dot. chat.js setStreamingState 가 토글. */
.chat-list-item-streaming {
    position: relative;
    padding-left: 1.25rem;
}
.chat-list-item-streaming::before {
    content: "";
    position: absolute;
    left: 0.45rem;
    top: 50%;
    width: 0.5rem;
    height: 0.5rem;
    margin-top: -0.25rem;
    border-radius: 50%;
    background: #22c55e; /* emerald-500 */
    box-shadow: 0 0 0 0 rgba(34, 197, 94, 0.55);
    animation: chat-streaming-pulse 1.4s ease-out infinite;
}
@keyframes chat-streaming-pulse {
    0%   { box-shadow: 0 0 0 0   rgba(34, 197, 94, 0.55); }
    70%  { box-shadow: 0 0 0 6px rgba(34, 197, 94, 0);    }
    100% { box-shadow: 0 0 0 0   rgba(34, 197, 94, 0);    }
}

/* ── Profile chip (사이드바 하단 sticky footer) ───────────────────────────
   .menu-list { flex:1 } 이 위쪽 공간 모두 흡수하므로 chip 은 자연히 바닥에 위치.
   iOS Safari 하단 bar 가림 대응: padding-bottom 에 env(safe-area-inset-bottom)
   를 더해 chip 이 항상 안전 영역 위로 떠 있음. 데스크탑·안드로이드는 env() = 0px 이라 영향 없음.
   .left-panel 의 1rem 좌우 padding 을 상쇄하려고 chip 자체 음수 margin 사용 → 풀폭 행. */
.left-profile-chip {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    margin: 0.75rem -1rem 0;            /* 위쪽 여유 + 좌우 padding 상쇄 */
    padding: 0.625rem 0.875rem;
    padding-bottom: calc(0.625rem + env(safe-area-inset-bottom, 0px));
    border-top: 1px solid var(--left-border);
    background: var(--left-bg);
    color: var(--color-text);
    text-decoration: none;
    cursor: pointer;
    min-height: 44px;                    /* iOS 최소 터치 타겟 */
    transition: background var(--transition);
}
.left-profile-chip:hover {
    background: var(--left-hover);
    text-decoration: none;
    color: var(--color-text);
}
.left-profile-chip.active {
    background: var(--left-active);
    font-weight: 600;
}
.left-profile-avatar {
    width: 1.75rem;
    height: 1.75rem;
    border-radius: 50%;
    background: var(--slate-700);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    font-weight: 600;
    flex-shrink: 0;
    overflow: hidden;
}
.left-profile-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}
.left-profile-name {
    flex: 1;
    font-size: 0.875rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.left-profile-icon {
    color: var(--color-text-muted);
    flex-shrink: 0;
}

/* ── 익명 로그인 슬롯 — 미인증 시 프로필 chip 대신 노출 ────────────── */
.left-anon-login {
    margin: 0.75rem -1rem 0;
    padding: 0.875rem 1rem;
    padding-bottom: calc(0.875rem + env(safe-area-inset-bottom, 0px));
    border-top: 1px solid var(--left-border);
    background: var(--left-bg);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}
.left-anon-label {
    font-size: 0.75rem;
    color: var(--color-text-muted);
    text-align: center;
}
.left-anon-google {
    display: flex;
    justify-content: center;
    min-height: 40px;
}