/* ═══════════════════════════════════════════════════════
   Message Turn Navigation – vertical rail on the right
   ═══════════════════════════════════════════════════════ */

/* ── Container ── */
.message-nav {
    position: absolute;
    right: 6px;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0;
    z-index: 40;
    padding: 4px 0;
    pointer-events: auto;
    opacity: 0;
    transition: opacity 0.25s ease;
}

.message-nav.is-disabled {
    display: none !important;
}

/* Only show when there are actual messages in the chat */
.message-nav.has-messages {
    opacity: 1;
}

/* Let ticks be a bit transparent until hover */
@media (hover: hover) and (pointer: fine) {
    .message-nav.has-messages:not(:hover) {
        opacity: 0.35;
    }
}

/* On hover the whole rail is fully visible */
.message-nav.has-messages:focus-within {
    opacity: 1;
}

@media (hover: hover) and (pointer: fine) {
    .message-nav.has-messages:hover {
        opacity: 1;
    }
}
/* ── Arrow buttons ── */
.message-nav-arrow {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: 8px;
    border: none;
    background: transparent;
    color: var(--text-color-secondary);
    cursor: pointer;
    flex-shrink: 0;
    opacity: 0;
    transform: scale(0.85);
    transition: opacity 0.2s ease,
                transform 0.2s ease,
                background-color 0.15s ease,
                color 0.15s ease;
    padding: 0;
}

@media (hover: hover) and (pointer: fine) {
    .message-nav:hover .message-nav-arrow {
        opacity: 1;
        transform: scale(1);
    }
}
@media (hover: none), (pointer: coarse) {
    .message-nav .message-nav-arrow {
        opacity: 1;
        transform: scale(1);
    }
}

@media (hover: hover) and (pointer: fine) {
    .message-nav-arrow:hover {
        background: var(--hover);
        color: var(--text-color);
    }
}

.message-nav-arrow:focus-visible {
    opacity: 1;
    transform: scale(1);
    background: var(--hover);
    color: var(--text-color);
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

.message-nav-arrow:focus:not(:focus-visible) {
    outline: none;
}

.message-nav-arrow:active {
    transform: scale(0.92) !important;
}

.message-nav-arrow:disabled {
    opacity: 0.25 !important;
    cursor: default;
    pointer-events: none;
}

.message-nav-arrow:disabled:focus-visible {
    outline: none;
}

/* ── Track (holds all ticks) ── */
.message-nav-track {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 3px;
    padding: 6px 0;
    width: 34px;
    box-sizing: border-box;
    overflow: visible;
}

.message-nav-track-scroll {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 3px;
    padding: 0 8px;
    box-sizing: border-box;
    max-height: 55vh;
    overflow-y: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

.message-nav-track-scroll::-webkit-scrollbar {
    display: none;
}

/* ── Tick (one per message turn) ── */
.message-nav-tick {
    width: 18px;
    height: 3px;
    border-radius: 2px;
    background: var(--text-color-secondary);
    opacity: 0.4;
    cursor: pointer;
    flex-shrink: 0;
    position: relative;
    transition: opacity 0.18s ease,
                background-color 0.18s ease,
                width 0.18s ease,
                height 0.18s ease,
                transform 0.15s ease,
                box-shadow 0.18s ease;
}

/* User ticks are slightly narrower */
.message-nav-tick[data-role="user"] {
    width: 12px;
    opacity: 0.3;
}

/* On rail hover, all ticks become more visible */
@media (hover: hover) and (pointer: fine) {
    .message-nav:hover .message-nav-tick {
        opacity: 0.5;
    }
}

@media (hover: hover) and (pointer: fine) {
    .message-nav:hover .message-nav-tick[data-role="user"] {
        opacity: 0.4;
    }
}

/* Individual tick hover */
@media (hover: hover) and (pointer: fine) {
    .message-nav-tick:hover {
        opacity: 1 !important;
        background: var(--text-color);
        height: 4px;
        transform: scaleX(1.15);
    }
}
@media (hover: none), (pointer: coarse) {
    .message-nav-tick {
        opacity: 1 !important;
        transform: scaleX(1.15);
    }
}

.message-nav-tick:focus-visible {
    opacity: 1 !important;
    background: var(--text-color);
    height: 4px;
    transform: scaleX(1.15);
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
    box-shadow: 0 0 0 2px var(--background);
}

.message-nav-tick:focus:not(:focus-visible) {
    outline: none;
}

/* Active (currently visible) tick */
.message-nav-tick.is-active {
    opacity: 0.9 !important;
    background: var(--text-color);
    height: 4px;
    width: 22px;
}

.message-nav-tick.is-active[data-role="user"] {
    width: 16px;
}

.message-nav-tick[data-role="user"]:focus-visible {
    width: 12px;
}

.message-nav-tick.is-active:focus-visible {
    width: 22px;
}

.message-nav-tick.is-active[data-role="user"]:focus-visible {
    width: 16px;
}

/* ── Tooltip ── */
.message-nav-tooltip {
    position: fixed;
    z-index: 200;
    max-width: 260px;
    min-width: 140px;
    padding: 10px 14px;
    background: var(--background);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.14),
                0 2px 8px rgba(0, 0, 0, 0.06);
    pointer-events: none;
    opacity: 0;
    transform: translateX(6px);
    transition: opacity 0.18s ease,
                transform 0.18s ease;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
}

.message-nav-tooltip.is-visible {
    opacity: 1;
    transform: translateX(0);
}

.message-nav-tooltip-role {
    font-size: 12px;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 4px;
    letter-spacing: 0.01em;
    line-height: 1.3;
}

.message-nav-tooltip-preview {
    font-size: 12px;
    line-height: 1.45;
    color: var(--text-color-secondary);
    display: -webkit-box;
    -webkit-line-clamp: 3;
    line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
    word-break: break-word;
}

/* ── Turn counter badge ── */
.message-nav-counter {
    font-size: 10px;
    font-weight: 600;
    color: var(--text-color-secondary);
    line-height: 1;
    padding: 2px 0;
    opacity: 0;
    transition: opacity 0.2s ease;
    user-select: none;
    -webkit-user-select: none;
}

@media (hover: hover) and (pointer: fine) {
    .message-nav:hover .message-nav-counter {
        opacity: 0.7;
    }
}

/* ── Hide on mobile / narrow screens ── */
@media (max-width: 900px) {
    .message-nav {
        display: none !important;
    }
     }

/* ── Also hide when a split screen is active ── */
body.split-screen-active .message-nav {
    display: none !important;
}

/* ── Compact mode: narrower chat area pushes nav in ── */
body.chat-area-compact .message-nav {
    right: 2px;
}