.sfis-container {
    position: relative;
    width: 100%;
    overflow: hidden;
}

/* Make sure swiper creates a positioning context */
.sfis-swiper {
    width: 100%;
    position: relative;
}

.sfis-container img {
    width: 100%;
    height: auto;
    display: block;
}

/* Navigation arrows overlay */
.sfis-container .swiper-button-prev,
.sfis-container .swiper-button-next {
    color: #fff;
    width: 44px;
    height: 44px;
    background: rgba(0,0,0,0.6);
    border-radius: 50%;
    top: 50%;
    transform: translateY(-50%);
    z-index: 50;
}

.sfis-container .swiper-button-prev {
    left: 10px;
}

.sfis-container .swiper-button-next {
    right: 10px;
}

.sfis-container .swiper-button-prev::after,
.sfis-container .swiper-button-next::after {
    font-size: 18px;
}

/* Fullscreen button (always on top of image) */
.sfis-fullscreen-btn {
    position: absolute;
    top: 10px;
    right: 10px;       /* top-right corner */
    z-index: 1000;     /* above everything */
    background: rgba(0,0,0,0.7);
    color: #fff;
    border: none;
    padding: 8px 10px;
    border-radius: 4px;
    cursor: pointer;
}

/* Keep button visible in fullscreen */
.sfis-container:fullscreen .sfis-fullscreen-btn {
    position: fixed;
    top: 10px;
    right: 10px;
    z-index: 2147483647; /* ultra top */
}