/* ========== Undo/Redo Buttons ========== */

.undo-redo-group {
    display: flex;
    align-items: center;
    gap: 2px;
}

.undo-redo-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border: none;
    border-radius: var(--planner-radius-sm, 6px);
    background: transparent;
    color: var(--planner-text-secondary, #6B6B6B);
    cursor: pointer;
    transition: background 0.15s, color 0.15s, opacity 0.15s;
}

.undo-redo-btn:hover:not(:disabled) {
    background: var(--planner-bg-hover, rgba(0, 0, 0, 0.06));
    color: var(--planner-text-primary, #1A1A1A);
}

.undo-redo-btn:disabled {
    opacity: 0.3;
    cursor: default;
}

.undo-redo-btn .icon {
    width: 18px;
    height: 18px;
}

/* Divider between undo/redo and other toolbar items */
.toolbar-divider {
    width: 1px;
    height: 20px;
    background: var(--planner-border, #E0E0E0);
    margin: 0 6px;
}

/* ========== Version History Panel ========== */

.version-history-panel {
    position: fixed;
    top: 0;
    right: 0;
    width: 340px;
    height: 100vh;
    background: var(--planner-bg-primary, #FFFFFF);
    border-left: 1px solid var(--planner-border, #E0E0E0);
    box-shadow: -4px 0 16px rgba(0, 0, 0, 0.08);
    z-index: 1000;
    display: flex;
    flex-direction: column;
    transition: transform 0.25s ease;
}

.version-history-panel.hidden {
    transform: translateX(100%);
    pointer-events: none;
}

.version-panel__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--planner-border, #E0E0E0);
    flex-shrink: 0;
}

.version-panel__title {
    font-size: 15px;
    font-weight: 600;
    color: var(--planner-text-primary, #1A1A1A);
    margin: 0;
}

.version-panel__close {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border: none;
    border-radius: var(--planner-radius-sm, 6px);
    background: transparent;
    color: var(--planner-text-secondary, #6B6B6B);
    cursor: pointer;
    font-size: 18px;
    line-height: 1;
}

.version-panel__close:hover {
    background: var(--planner-bg-hover, rgba(0, 0, 0, 0.06));
}

.version-panel__actions {
    display: flex;
    gap: 8px;
    padding: 12px 20px;
    border-bottom: 1px solid var(--planner-border, #E0E0E0);
    flex-shrink: 0;
}

.version-save-btn {
    flex: 1;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 8px 12px;
    border: 1px solid var(--planner-border, #E0E0E0);
    border-radius: var(--planner-radius-sm, 6px);
    background: var(--planner-bg-primary, #FFFFFF);
    color: var(--planner-text-primary, #1A1A1A);
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.15s, border-color 0.15s;
}

.version-save-btn:hover {
    background: var(--planner-bg-hover, rgba(0, 0, 0, 0.04));
    border-color: var(--planner-text-secondary, #6B6B6B);
}

.version-save-btn .icon {
    width: 16px;
    height: 16px;
}

/* ========== Version List ========== */

.version-list {
    flex: 1;
    overflow-y: auto;
    padding: 8px 0;
}

.version-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 20px;
    gap: 12px;
    transition: background 0.15s;
}

.version-item:hover {
    background: var(--planner-bg-hover, rgba(0, 0, 0, 0.03));
}

.version-item__info {
    flex: 1;
    min-width: 0;
}

.version-item__header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 2px;
}

.version-item__name {
    font-size: 13px;
    font-weight: 500;
    color: var(--planner-text-primary, #1A1A1A);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.version-badge {
    font-size: 10px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.03em;
    padding: 2px 6px;
    border-radius: 3px;
    flex-shrink: 0;
}

.version-badge--auto {
    background: var(--planner-bg-hover, #F0F0F0);
    color: var(--planner-text-secondary, #6B6B6B);
}

.version-badge--manual {
    background: #EBF5FF;
    color: #1D6FBF;
}

.version-item__meta {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 12px;
    color: var(--planner-text-secondary, #6B6B6B);
}

.version-item__actions {
    display: flex;
    align-items: center;
    gap: 4px;
    opacity: 0;
    transition: opacity 0.15s;
    flex-shrink: 0;
}

.version-item:hover .version-item__actions {
    opacity: 1;
}

.version-action-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 4px 10px;
    border: 1px solid transparent;
    border-radius: var(--planner-radius-sm, 6px);
    background: transparent;
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.15s, border-color 0.15s;
}

.version-restore-btn {
    color: #1D6FBF;
    border-color: #1D6FBF;
}

.version-restore-btn:hover {
    background: #EBF5FF;
}

.version-delete-btn {
    color: var(--planner-text-secondary, #6B6B6B);
    font-size: 16px;
    padding: 2px 6px;
}

.version-delete-btn:hover {
    color: var(--planner-red, #E54D4D);
    background: #FFF0F0;
}

/* ========== Empty & Loading States ========== */

.version-empty {
    padding: 40px 20px;
    text-align: center;
}

.version-empty p {
    font-size: 14px;
    color: var(--planner-text-secondary, #6B6B6B);
    margin: 0 0 8px;
}

.version-empty__hint {
    font-size: 12px;
    color: var(--planner-text-tertiary, #999);
}

.version-loading {
    padding: 40px 20px;
    text-align: center;
    font-size: 13px;
    color: var(--planner-text-secondary, #6B6B6B);
}

/* ========== Version History Button ========== */

.version-history-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border: 1px solid var(--planner-border, #E0E0E0);
    border-radius: var(--planner-radius-sm, 6px);
    background: var(--planner-bg-primary, #FFFFFF);
    color: var(--planner-text-secondary, #6B6B6B);
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.15s, border-color 0.15s, color 0.15s;
}

.version-history-btn:hover {
    background: var(--planner-bg-hover, rgba(0, 0, 0, 0.04));
    border-color: var(--planner-text-secondary, #6B6B6B);
    color: var(--planner-text-primary, #1A1A1A);
}

.version-history-btn .icon {
    width: 16px;
    height: 16px;
}

/* ========== Responsive ========== */

@media (max-width: 768px) {
    .version-history-panel {
        width: 100%;
    }

    .undo-redo-group {
        gap: 0;
    }

    .version-history-btn span {
        display: none;
    }
}