/* 
  한스다이브 디자인 시스템 (dark & sea blue theme)
*/
:root {
    --primary-color: #0d84f8;
    /* 바다를 연상시키는 블루 */
    --primary-dark: #0056b3;
    --text-color: #f1f2f6;
    /* 어두운 배경 대비 밝은 텍스트 */
    --text-muted: #a4b0be;
    --bg-dark: #0f141e;
    /* 심해 느낌의 다크 네이비 */
    --bg-light: #161e2e;
    --header-bg: rgba(15, 20, 30, 0.95);

    --transition: 0.3s ease-in-out;
    --border-radius: 12px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Pretendard Variable', Pretendard, -apple-system, BlinkMacSystemFont, system-ui, Roboto, "Helvetica Neue", "Segoe UI", "Apple SD Gothic Neo", "Noto Sans KR", "Malgun Gothic", "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", sans-serif;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-color);
    line-height: 1.6;
    overflow-x: hidden;
}

html {
    scroll-behavior: smooth;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

ul {
    list-style: none;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 28px;
    border-radius: 30px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    border: none;
    white-space: nowrap;
}

.btn-primary {
    background-color: var(--primary-color);
    color: #fff;
    box-shadow: 0 4px 15px rgba(13, 132, 248, 0.4);
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(13, 132, 248, 0.6);
}

.btn-outline {
    background-color: transparent;
    color: #fff;
    border: 2px solid rgba(255, 255, 255, 0.5);
}

.btn-outline:hover {
    background-color: rgba(255, 255, 255, 0.1);
    border-color: #fff;
}

.btn-block {
    width: 100%;
}

/* Typography & Sections */
.section {
    padding: 100px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 15px;
    color: #fff;
}

.section-header p {
    color: var(--text-muted);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
}

.bg-light {
    background-color: var(--bg-light);
}

/* Header */
.header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    transition: var(--transition);
    padding: 20px 0;
}

.header.scrolled {
    background-color: var(--header-bg);
    padding: 15px 0;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(10px);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: #fff;
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo i {
    color: var(--primary-color);
    font-size: 2rem;
}

.nav-menu {
    display: flex;
    gap: 30px;
}

.nav-link {
    font-weight: 500;
    font-size: 1.05rem;
    position: relative;
    padding-bottom: 5px;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0%;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

/* Hamburger */
.hamburger {
    display: none;
    cursor: pointer;
}

.hamburger .bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 5px auto;
    transition: all 0.3s ease-in-out;
    background-color: #fff;
}

/* Hero Section (YouTube Background) */
.hero {
    position: relative;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

/* 유튜브 Iframe 영역 */
.video-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
}

.video-foreground {
    /* 화면 비율 유지를 위해 16:9 패딩 트릭 활용 혹은 넓게 깔기 */
    position: absolute;
    top: 50%;
    left: 50%;
    width: 100vw;
    height: 56.25vw;
    /* 16:9 = 9/16 = 56.25% */
    min-height: 100vh;
    min-width: 177.77vh;
    /* 16/9 = 177.77% */
    transform: translate(-50%, -50%);
    pointer-events: none;
    /* 영상이 클릭을 막지 않게 */
}

#youtube-player {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

/* 가독성을 높이는 어두운 그림자(오버레이) */
.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom,
            rgba(15, 20, 30, 0.7) 0%,
            rgba(15, 20, 30, 0.3) 50%,
            rgba(15, 20, 30, 0.8) 100%);
}

.hero-content {
    text-align: center;
    position: relative;
    z-index: 1;
}

.subtitle {
    display: inline-block;
    padding: 8px 16px;
    background: rgba(13, 132, 248, 0.1);
    border: 1px solid rgba(13, 132, 248, 0.3);
    border-radius: 20px;
    color: var(--primary-color);
    font-weight: 600;
    margin-bottom: 20px;
    letter-spacing: 1px;
}

.hero .title {
    font-size: 4.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 25px;
    color: #fff;
    text-shadow: 0 4px 10px rgba(0, 0, 0, 0.5);
}

.hero .title span {
    color: var(--primary-color);
}

.hero .description {
    font-size: 1.2rem;
    color: #e2e8f0;
    margin-bottom: 40px;
    text-shadow: 0 2px 5px rgba(0, 0, 0, 0.5);
}

.hero-btns {
    display: flex;
    justify-content: center;
    gap: 20px;
}

/* 마우스 스크롤 아이콘 */
.scroll-down {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
}

.scroll-down i {
    font-size: 2.5rem;
    color: rgba(255, 255, 255, 0.7);
    transition: var(--transition);
}

.scroll-down:hover i {
    color: #fff;
}

@keyframes bounce {

    0%,
    20%,
    50%,
    80%,
    100% {
        transform: translateY(0);
    }

    40% {
        transform: translateY(-20px);
    }

    60% {
        transform: translateY(-10px);
    }
}

/* About Section */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-text h3 {
    font-size: 2rem;
    margin-bottom: 20px;
    line-height: 1.4;
    color: #fff;
}

.about-text p {
    color: var(--text-muted);
    margin-bottom: 20px;
    font-size: 1.05rem;
}

.features-list {
    margin-top: 40px;
}

.feature-item {
    display: flex;
    align-items: flex-start;
    gap: 20px;
    margin-bottom: 30px;
    padding: 20px;
    background: var(--bg-light);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
}

.feature-item:hover {
    transform: translateY(-5px);
    border-color: rgba(13, 132, 248, 0.3);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.feature-item i {
    font-size: 2.5rem;
    color: var(--primary-color);
}

.feature-item h4 {
    font-size: 1.2rem;
    margin-bottom: 5px;
    color: #fff;
}

.feature-item span {
    color: var(--text-muted);
    font-size: 0.95rem;
}

.about-img {
    position: relative;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
}

.about-img::before {
    content: '';
    position: absolute;
    inset: 0;
    border: 2px solid rgba(13, 132, 248, 0.5);
    border-radius: var(--border-radius);
    z-index: 1;
    pointer-events: none;
    margin: 15px;
}

.about-img img {
    width: 100%;
    height: auto;
    display: block;
    transition: transform 0.5s ease;
}

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

/* Services */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.service-card {
    background: var(--bg-dark);
    padding: 40px 30px;
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--primary-color);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.4s ease;
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3);
}

.service-card:hover::before {
    transform: scaleX(1);
}

.service-icon {
    width: 60px;
    height: 60px;
    background: rgba(13, 132, 248, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 25px;
}

.service-icon i {
    font-size: 2rem;
    color: var(--primary-color);
}

.service-card h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: #fff;
}

.service-card p {
    color: var(--text-muted);
    margin-bottom: 25px;
    font-size: 0.95rem;
}

.service-link {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    color: var(--primary-color);
    font-weight: 600;
}

.service-link:hover {
    gap: 10px;
}

/* Stats */
.stats {
    padding: 60px 0;
    background: linear-gradient(rgba(13, 132, 248, 0.9), rgba(0, 86, 179, 0.9)), url('https://images.unsplash.com/photo-1582239634281-995cbf5d96ca?auto=format&fit=crop&q=80') center/cover;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    text-align: center;
    gap: 40px;
}

.stat-item {
    color: #fff;
}

.stat-number {
    display: block;
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 10px;
}

.stat-text {
    font-size: 1.1rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 2px;
}

/* Contact */
.contact-wrap {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    background: var(--bg-light);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.contact-info {
    padding: 50px;
    background: linear-gradient(135deg, rgba(15, 20, 30, 0.8), rgba(13, 132, 248, 0.1));
}

.contact-info h3 {
    font-size: 1.8rem;
    margin-bottom: 15px;
    color: #fff;
}

.contact-info p {
    color: var(--text-muted);
    margin-bottom: 40px;
}

.info-list li {
    display: flex;
    align-items: flex-start;
    gap: 20px;
    margin-bottom: 30px;
}

.info-list i {
    font-size: 1.8rem;
    color: var(--primary-color);
    background: rgba(13, 132, 248, 0.1);
    padding: 12px;
    border-radius: 50%;
}

.info-list span {
    display: block;
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 5px;
}

.info-list strong {
    color: #fff;
    font-size: 1.1rem;
}

.contact-form {
    padding: 50px;
}

.form-group {
    margin-bottom: 25px;
}

.form-control {
    width: 100%;
    padding: 15px 20px;
    background: var(--bg-dark);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    color: #fff;
    font-size: 1rem;
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(13, 132, 248, 0.2);
}

textarea.form-control {
    resize: vertical;
}

/* Footer */
.footer {
    background-color: #080b11;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    padding: 30px 0;
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-logo {
    font-weight: 800;
    font-size: 1.2rem;
    color: #fff;
}

.footer-bottom p {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.footer-links a {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-left: 20px;
}

.footer-links a:hover {
    color: var(--primary-color);
}

/* Responsive */
@media (max-width: 992px) {
    .hero .title {
        font-size: 3.5rem;
    }

    .about-grid,
    .contact-wrap {
        grid-template-columns: 1fr;
    }

    .about-img {
        order: -1;
    }

    /* 이미지 위로 올림 */
}

@media (max-width: 768px) {
    .hamburger {
        display: block;
    }

    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        /* 헤더 높이만큼 띄움 */
        gap: 0;
        flex-direction: column;
        background-color: var(--header-bg);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 20px rgba(0, 0, 0, 0.5);
        backdrop-filter: blur(10px);
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-menu li {
        margin: 16px 0;
    }

    .hero .title {
        font-size: 2.5rem;
    }

    .hero .description {
        font-size: 1rem;
    }

    .hero-btns {
        gap: 10px;
    }

    .hero-btns .btn {
        padding: 10px 15px;
        font-size: 0.9rem;
    }

    .stats-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .contact-info,
    .contact-form {
        padding: 30px 20px;
    }

    .footer-bottom {
        justify-content: center;
        text-align: center;
    }
}