.sts-track {
    position: relative;
    overflow: hidden;
    width: 100%;
    max-width: 300px;
    height: 48px;
    border: 2px solid var(--green-primary);
    border-radius: 24px;
    background: var(--grey-white, #f5f5f5);
    user-select: none;
    -webkit-user-select: none;
    touch-action: none;
}

.sts-track .sts-fill {
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 0%;
    background: var(--green-primary);
    opacity: 0.15;
    pointer-events: none;
}

.sts-track .sts-label {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: bold;
    color: var(--grey-primary, #666);
    pointer-events: none;
    z-index: 1;
}

.sts-track .sts-handle {
    position: absolute;
    top: 2px;
    left: 2px;
    width: 42px;
    height: 42px;
    border-radius: 50%;
    background: var(--green-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: grab;
    z-index: 2;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
}

.sts-track .sts-handle:active {
    cursor: grabbing;
}

.sts-track .sts-handle .sts-arrow {
    color: var(--white, #ffffff);
    font-size: 14px;
    letter-spacing: -3px;
    padding-left: 2px;
}

.sts-track.sts-dragging .sts-handle {
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.sts-track.sts-done {
    border-color: var(--green-primary);
    background: var(--green-light, #e8f5e9);
}

.sts-track.sts-done .sts-label {
    color: var(--green-primary);
}

.sts-track.sts-done .sts-handle {
    cursor: default;
}

.sts-track.sts-done .sts-fill {
    opacity: 0.25;
}