/*
 * Full-page file drop overlay.
 *
 * The overlay intentionally mirrors the small drag-and-drop demo: one quiet
 * backdrop and one obvious drop target. Upload routing remains in the chat and
 * Workspace Files controllers, so this presentation is shared by both flows.
 */
.drop-overlay {
    position: fixed;
    inset: 0;
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    background: color-mix(in srgb, var(--background) 72%, transparent);
    backdrop-filter: var(--modal-overlay-backdrop-filter);
    -webkit-backdrop-filter: var(--modal-overlay-backdrop-filter);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.18s ease;
}

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

.drop-overlay-dropzone {
    display: flex;
    width: min(560px, 86vw);
    min-height: 280px;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 48px 32px;
    border: 2px dashed var(--border-color);
    border-radius: 22px;
    background: var(--surface-elevated);
    box-shadow: var(--surface-elevated-shadow);
    color: var(--text-color);
    text-align: center;
    transform: scale(0.97);
    transition:
        border-color 0.18s ease,
        transform 0.18s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.drop-overlay.active .drop-overlay-dropzone {
    border-color: var(--text-color);
    transform: scale(1);
}

.drop-overlay-icon {
    display: inline-flex;
    width: 48px;
    height: 48px;
    margin-bottom: 20px;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    animation: drop-overlay-pulse 1.6s ease-in-out infinite;
}

.drop-overlay-icon svg {
    width: 100%;
    height: 100%;
}

.drop-overlay-dropzone h2 {
    margin: 0 0 6px;
    color: var(--text-color);
    font-size: 20px;
    font-weight: 600;
    line-height: 1.3;
    letter-spacing: -0.01em;
}

.drop-overlay-dropzone p {
    max-width: 42ch;
    margin: 0;
    color: var(--text-color-secondary);
    font-size: 14px;
    line-height: 1.5;
}

@media (max-width: 480px), (max-height: 480px) {
    .drop-overlay {
        padding: 16px;
    }

    .drop-overlay-dropzone {
        min-height: 200px;
        padding: 32px 24px;
    }
}

@media (prefers-reduced-motion: reduce) {
    .drop-overlay,
    .drop-overlay-dropzone {
        transition: none;
    }

    .drop-overlay-icon {
        animation: none;
    }
}

@media (forced-colors: active) {
    .drop-overlay {
        background: Canvas;
    }

    .drop-overlay-dropzone {
        border-color: CanvasText;
        background: Canvas;
        box-shadow: none;
        color: CanvasText;
    }
}