/* =================================
   1. 전역 & 데스크탑 스타일
   ================================= */
body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    background-color: #000000;
    color: #ffffff;
    font-family: 'Pretendard', sans-serif;
}

/* 애니메이션은 한 번만 정의합니다. */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    padding: 25px 50px;
    box-sizing: border-box;
    display: flex;
    justify-content: space-between;
    align-items: center;
    animation: fadeIn 1s ease-out;
    z-index: 10;
}

.logo img {height: 80px; transition: transform 0.4s ease;}
.logo img:hover {transform: scale(1.05);}
header nav.desktop-menu { display: block; }
#mobile-menu { display: none; } /* 모바일 메뉴는 기본적으로 숨김 */
.hamburger-menu { display: none; }
nav ul { list-style: none; margin: 0; padding: 0; display: flex; gap: 40px; }
nav a { color: #e0e0e0; text-decoration: none; font-size: 16px; font-weight: 500; letter-spacing: 1px; }
nav a:hover { color: #5ea6ff; }
.logo img { height: 80px; }

main {padding-top: 130px;} /* 헤더의 대략적인 높이 */
/* --- 비디오 오버레이 --- */
.image-overlay-container {
    position: relative;
    width: 100%;
    /* 화면 높이를 100% 채우도록 수정 */
    height: 100vh;
}
.overlay-text {
    position: relative;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: #ffffff;
    text-align: center;
    padding: 20px;
    box-sizing: border-box;
    z-index: 4;
}

.overlay-text::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    border-radius: inherit;
    z-index: -1;
}

.overlay-text .slogan {
    font-size: 48px;
    font-weight: 700;
    margin: 0 0 20px 0;
    letter-spacing: -1px;
}

.overlay-text .description {
    font-size: 17px;
    line-height: 1.7;
    font-weight: 400;
    max-width: 650px;
    margin: 0 auto;
}

/* --- 푸터 --- */
footer {
    width: 100%;
    background-color: #000000;
    color: #a0a0a0;
    padding: 30px 50px;
    box-sizing: border-box;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
    font-size: 14px;
    animation: fadeIn 1s ease-out;
}

.footer-top {
    display: flex;
    align-items: center;
    gap: 30px;
}

.footer-nav ul {
    gap: 20px;
}

.footer-nav a, .social-icons a {
    color: #a0a0a0;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-nav a:hover, .social-icons a:hover {
    color: #ffffff;
}

.social-icons a {
    font-size: 18px;
    margin: 0 10px;
}

.copyright {
    font-size: 12px;
    margin-top: 15px;
}


/* =================================
   2. 모바일 스타일
   ================================= */
@media (max-width: 768px) {
    header {
        padding: 15px 20px;
        justify-content: center;
    }

    header nav.desktop-menu {
        display: none; 
    }

    .logo img {
        height: 50px;
    }

    /* --- 햄버거 메뉴 --- */
    .hamburger-menu {
        /* [정리] 중복 속성 제거 */
        position: absolute;
        left: 20px;
        top: 50%;
        transform: translateY(-50%);
        display: flex;
        flex-direction: column;
        gap: 5px;
        cursor: pointer;
    }
    
    .hamburger-menu .bar {
        width: 25px;
        height: 3px;
        background-color: #ffffff;
    }

    /* --- 모바일 메뉴 (클릭 시 나타나는 부분) --- */
    #mobile-menu {
        display: none; /* 기본 숨김 */
    }

    #mobile-menu.is-active {
        display: block;
        position: absolute;
        top: 80px;
        left: 0;
        width: 100%;
        background-color: rgba(0, 0, 0, 0.85); /* 약간의 투명도 조정 */
        padding: 15px 0;
        animation: fadeIn 0.4s ease-out;
        z-index: 100;
    }
    
    /* [수정] flex를 추가하여 정렬 적용 & 중복 제거 */
    #mobile-menu.is-active ul {
        display: flex;
        flex-direction: column;
        align-items: center;
    }

    #mobile-menu.is-active ul li a {
        color: white;
        padding: 12px 20px;
        font-size: 18px;
        display: block;
    }
    
    /* --- 모바일 기타 스타일 --- */
    main {
        padding-top: 80px;
    }

    .image-overlay-container {
        margin-top: 80px; /* 헤더 높이에 맞게 조정 */
    }

    .overlay-text .slogan {
        font-size: 24px;
    }

    .overlay-text .description {
        font-size: 14px;
        padding: 0 15px;
    }
    
    footer {
        margin-top: 60px;
        padding: 20px;
    }

    .footer-top {
        flex-direction: column;
        gap: 20px;
        font-size: 12px;
    }
}