.ihk-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s, visibility 0.2s;
}

.ihk-overlay.active {
    opacity: 1;
    visibility: visible;
}

.ihk-box {
    background: var(--bg-deep);
    width: 100%;
    max-width: 700px;
    max-height: 90vh;
    border-radius: var(--radius);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2), 0 0 0 1px var(--border);
    display: flex;
    flex-direction: column;
    transform: translateY(20px) scale(0.98);
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.1);
    overflow: hidden;
}

.ihk-overlay.active .ihk-box {
    transform: translateY(0) scale(1);
}

.ihk-head {
    display: flex;
    align-items: flex-start;
    padding: 1.5rem;
    gap: 1rem;
    border-bottom: 1px solid var(--border);
    position: relative;
    background: var(--bg-surface);
}

.ihk-head-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: rgba(var(--primary-rgb), 0.1);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.ihk-head-text h3 {
    margin: 0 0 0.25rem 0;
    font-size: 1.25rem;
    font-weight: 700;
}

.ihk-head-text p {
    margin: 0;
    color: var(--text-muted);
    font-size: 0.9rem;
    line-height: 1.4;
}

.ihk-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: transparent;
    border: none;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background 0.2s;
}

.ihk-close:hover {
    background: var(--bg-hover);
    color: var(--text-main);
}

.ihk-body {
    padding: 1.5rem;
    overflow-y: auto;
    flex: 1;
}

.ihk-error {
    background: rgba(220, 38, 38, 0.1);
    color: #dc2626;
    padding: 1rem;
    border-radius: var(--radius-sm);
    margin-bottom: 1rem;
    font-size: 0.9rem;
    border: 1px solid rgba(220, 38, 38, 0.2);
}

.ihk-drop {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem 1.5rem;
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    background: var(--bg-surface);
    cursor: pointer;
    transition: border-color 0.2s, background 0.2s;
    text-align: center;
}

.ihk-drop:hover, .ihk-drop.dragover {
    border-color: var(--primary);
    background: rgba(var(--primary-rgb), 0.02);
}

.ihk-drop-icon {
    width: 48px;
    height: 48px;
    color: var(--primary);
    margin-bottom: 1rem;
    opacity: 0.8;
}

.ihk-drop-main {
    font-weight: 600;
    font-size: 1.1rem;
    margin-bottom: 0.25rem;
    display: block;
}

.ihk-drop-sub {
    color: var(--text-muted);
    font-size: 0.9rem;
    display: block;
}

.ihk-facts {
    margin: 1.5rem 0 0 0;
    padding: 0 0 0 1.25rem;
    color: var(--text-dim);
    font-size: 0.85rem;
    line-height: 1.5;
}

.ihk-facts li {
    margin-bottom: 0.5rem;
}

.ihk-busy-text {
    font-weight: 600;
    text-align: center;
    margin-bottom: 1rem;
}

.ihk-bar-track {
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 0.75rem;
}

.ihk-bar {
    height: 100%;
    background: var(--primary);
    width: 0%;
    transition: width 0.3s;
    border-radius: 3px;
}

.ihk-hint {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.85rem;
    margin: 0;
}

.ihk-meta {
    background: var(--bg-surface);
    padding: 1rem;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    margin-bottom: 1.5rem;
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    font-size: 0.9rem;
}

.ihk-meta-item {
    display: flex;
    flex-direction: column;
}

.ihk-meta-label {
    color: var(--text-muted);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.2rem;
}

.ihk-meta-val {
    font-weight: 600;
}

.ihk-weeks-head {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.75rem;
}

.ihk-weeks-title {
    font-weight: 600;
    font-size: 1.05rem;
}

.ihk-weeks-actions {
    display: flex;
    gap: 0.5rem;
}

.ihk-weeks-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    max-height: 350px;
    overflow-y: auto;
    margin-bottom: 1.5rem;
    padding-right: 0.5rem;
}

.ihk-week-card {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: border-color 0.2s, background 0.2s;
    user-select: none;
}

.ihk-week-card:hover {
    border-color: var(--primary-light);
}

.ihk-week-card.selected {
    border-color: var(--primary);
    background: rgba(var(--primary-rgb), 0.02);
}

.ihk-week-card.duplicate {
    opacity: 0.6;
}

.ihk-week-card.duplicate:hover {
    opacity: 0.8;
}

.ihk-week-check {
    margin-right: 1rem;
}

.ihk-week-info {
    flex: 1;
}

.ihk-week-dates {
    font-weight: 600;
    display: block;
    margin-bottom: 0.15rem;
}

.ihk-week-details {
    font-size: 0.8rem;
    color: var(--text-muted);
    display: flex;
    gap: 0.75rem;
}

.ihk-week-duplicate-badge {
    font-size: 0.7rem;
    background: rgba(var(--warning-rgb), 0.15);
    color: var(--warning);
    padding: 0.1rem 0.4rem;
    border-radius: 10px;
    font-weight: 600;
}

.ihk-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

@media (max-width: 600px) {
    .ihk-meta {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .ihk-actions {
        flex-direction: column-reverse;
    }
    
    .ihk-actions button {
        width: 100%;
    }
}