/*reset 초기화*/
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-weight: 400;
    color: #111;
}

@media (max-width: 580px) {
    html { font-size: 15px; }
}
@media (max-width: 480px) {
    html { font-size: 14px; }
}
@media (max-width: 360px) {
    html { font-size: 13px; }
}


@media (max-width: 580px) {
    .black_bg {
        padding: 0 10px;
    }
}

/* #region 공통 
*/

img{
    border-radius: 10px;
    width: 100%;
}
.black_bg img{
    border: 4px solid transparent; /* 투명 테두리 */
    background: 
        linear-gradient(#fff, #fff) padding-box, /* 내부 흰색 배경 */
        linear-gradient(90deg, #B58727 0%, #FFECAB 50%, #B58727 100%) border-box; /* 외곽선 그라데이션 */
}

/* #endregion */
/* #region 1. 상단 
*/

.best_wrap{
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin: auto;
}
.best_wrap>*{
    flex: 1;
    max-width: 400px;
    text-align: center;
}
.best_wrap h3{
    font-size: 1.3rem;
    font-weight: 500;
    margin: 2rem 0 1rem 0;
    line-height: 140%;
}
.best_wrap h4{
    color: #707070;
    line-height: 150%;
    font-size: 1.07rem;
}




@media (max-width: 480px) {
    .best_wrap h3 {
        font-size: 1.1rem;
    }
    .best_wrap h4 {
        font-size: .95rem;
    }
}

/* #endregion */
/* #region 2. 탭메뉴 
*/
.tab_menu_wrap {
    margin: 7rem auto 4rem auto;
}
.tab_menu {
    justify-content: space-around;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    text-align: center;

}
.tab_menu .tab_btn {
    flex: 1;
    text-align: center;
    padding: 1.5rem 0;
    font-size: 0.95rem;
    color: #888;
    cursor: pointer;
    background: #f4f4f4;
    transition: all 0.2s ease;
}
.tab_section.active {
    display: block;
}
/* 활성화된 탭 */
.tab_menu .tab_btn.active {
    color: #f15a40;
    font-weight: 600;
    background: #fff;
    outline: 1px solid #f15a40;
    z-index: 1; /* 활성 탭이 위로 올라오게 */
}

@media (max-width:580px) {
    .tab_menu {
        grid-template-columns: repeat(2, 1fr);
    }
        .tab_menu .tab_btn {
            font-size: 1.1rem;
            padding: 1.65rem 0;
        }
}
/* #endregion */



/* #region 3. 이미지 호버효과
*/
.patent_list{
    justify-content: space-around;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 5rem;
    text-align center;
}
.patent_card {
    text-align: center;
    transition: transform 0.3s ease;
}
.patent_card:hover {
    transform: translateY(-5px);
}
.patent_img {
    position: relative;
}
.patent_img img {
    width: 100%;
    height: auto;
    display: block;
}

/* 오버레이 기본 숨김 */
.patent_overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.65);
    color: #fff;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    opacity: 0;
    border-radius: 10px;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
    padding: 20px;
}

/* hover 시 나타남 */
.patent_img:hover .patent_overlay {
    opacity: 1;
    visibility: visible;
}
.patent_overlay h3 {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: #fff;
}
.patent_overlay p {
    font-size: 0.93rem;
    line-height: 150%;
    text-align: center;
    color: #fff;
}
.patent_info {
    padding: 1.2rem 0;
}
.patent_info h3 {
    font-size: 1.07rem;
    font-weight: 600;
    color: #333;
    margin-bottom: 10px;
    line-height: 140%;
}
.patent_info h4 {
    font-size: 0.93rem;
    color: #888;
    line-height: 140%;
}





@media (max-width: 768px) {
    .patent_list {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
    }
}
@media (max-width: 580px) {
    .patent_list {
        gap: 1rem;
    }
}
@media (max-width: 360px) {
    .patent_list {
        grid-template-columns: repeat(1, 1fr);
        row-gap: 2rem;
    }
        .patent_overlay h3 {
        font-size: 1.5rem;
    }
    .patent_overlay p {
        font-size: 1.2rem;
    }
    .patent_info h3 {
        font-size: 1.3rem;
    }
    .patent_info h4 {
        font-size: 1.15rem;
    }
}

/* #endregion */