/* 애니메이션 효과 추가 */
.step, .component-card, .advantage-item, .disadvantage-item, .timeline-item {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.step.visible, .component-card.visible, .advantage-item.visible, .disadvantage-item.visible, .timeline-item.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 스크롤 시 네비게이션 바 스타일 변경 */
nav.scrolled {
    background-color: rgba(13, 71, 161, 0.95);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

/* 이미지 호버 효과 */
.responsive-img {
    transition: transform 0.3s ease;
}

.responsive-img:hover {
    transform: scale(1.05);
}

/* 버튼 스타일 */
.btn {
    display: inline-block;
    background-color: var(--primary-color);
    color: var(--light-text);
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    text-decoration: none;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-weight: bold;
    margin-top: 1rem;
}

.btn:hover {
    background-color: var(--secondary-color);
    transform: translateY(-3px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

/* 섹션 구분선 */
section:not(:last-child) {
    border-bottom: 1px solid #eee;
    padding-bottom: 2rem;
}

/* 강조 텍스트 */
.highlight {
    background-color: var(--light-color);
    color: var(--primary-color);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-weight: bold;
}

/* 로딩 애니메이션 */
.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(255, 255, 255, 0.9);
    z-index: 9999;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 5px solid var(--light-color);
    border-top: 5px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* 페이지 상단으로 이동 버튼 */
.back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background-color: var(--primary-color);
    color: var(--light-text);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    text-decoration: none;
    opacity: 0;
    transition: opacity 0.3s ease;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
    z-index: 99;
}

.back-to-top.visible {
    opacity: 1;
}

.back-to-top:hover {
    background-color: var(--secondary-color);
}