/* Global Styles & Variables */
:root {
    --primary-color: #0077cc; /* Aqua Blue */
    --secondary-color: #005fa3;
    --dark-bg: #2c3e50;
    --light-bg: #f4f7f9;
    --text-color: #34495e;
    --header-height: 70px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    /* 부드러운 스크롤 활성화 */
    scroll-behavior: smooth;
    /* Sticky Header가 메뉴 이동 시 콘텐츠 상단을 가리지 않도록 설정 */
    scroll-padding-top: var(--header-height); 
}

body {
    font-family: 'Noto Sans KR', 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #ffffff;
}

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

a {
    text-decoration: none;
}

img {
    max-width: 100%;
    height: auto;
}

/* Layout */
.section {
    padding: 100px 0;
}

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

h2 {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 60px;
    position: relative;
    color: var(--dark-bg);
}

h2::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background-color: var(--primary-color);
    margin: 15px auto 0;
}

/* Header & Navigation (Sticky) */
header {
    background-color: rgba(255, 255, 255, 0.98);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
    height: var(--header-height);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

.logo {
    font-size: 1.8rem;
    font-weight: bold;
    color: var(--primary-color);
    font-family: 'Roboto', sans-serif;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 30px;
}

nav ul li a {
    color: var(--dark-bg);
    font-weight: 500;
    transition: color 0.3s;
}

nav ul li a:hover {
    color: var(--primary-color);
}

/* Language Switcher */
.language-switcher button {
    background: none;
    border: none;
    margin-left: 10px;
    cursor: pointer;
    font-weight: bold;
    color: #aaa;
    transition: color 0.3s;
}

.language-switcher button.active {
    color: var(--primary-color);
    text-decoration: underline;
}

/* Hero Section (Video Background) */
.hero-section {
    height: 85vh;
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    color: #ffffff;
    text-align: center;
}

#bg-video {
    position: absolute;
    top: 50%;
    left: 50%;
    min-width: 100%;
    min-height: 100%;
    width: auto;
    height: auto;
    z-index: -2;
    transform: translate(-50%, -50%);
    background: var(--dark-bg); /* 비디오 로딩 전 배경색 */
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    /* 어두운 오버레이로 텍스트 가독성 확보 */
    background-color: rgba(0, 0, 0, 0.5); 
    z-index: -1;
}

.hero-content h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
}

.hero-content p {
    font-size: 1.5rem;
    margin-bottom: 30px;
}

/* CTA Button */
.cta-button {
    display: inline-block;
    background-color: var(--primary-color);
    color: #ffffff;
    padding: 12px 30px;
    border-radius: 50px;
    font-weight: bold;
    transition: background-color 0.3s, transform 0.3s;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.cta-button:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
}

/* About Section */
.about-content {
    display: flex;
    align-items: center;
    gap: 50px;
}

.about-text {
    flex: 1;
}

.about-text p {
    margin-bottom: 15px;
    font-size: 1.1rem;
}

.about-image {
    flex: 1;
}

.about-image img {
    border-radius: 8px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

/* Services Section */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.service-item {
    background-color: #ffffff;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.05);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    overflow: hidden;
}

.service-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 30px rgba(0,0,0,0.15);
}

.service-item img {
    width: 100%;
    height: 200px;
    object-fit: cover; /* 이미지 비율 유지하며 채우기 */
}

.service-info {
    padding: 25px;
}

.service-item h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
    color: var(--dark-bg);
}

.service-item p {
    margin-bottom: 20px;
}

.service-link {
    color: var(--primary-color);
    font-weight: bold;
}

.service-link:hover {
    color: var(--secondary-color);
}

.future-plans {
    text-align: center;
    font-size: 1.2rem;
    font-style: italic;
    padding-top: 20px;
}

/* Contact Section */
.contact-intro {
    text-align: center;
    margin-bottom: 40px;
}

form {
    max-width: 600px;
    margin: 0 auto;
}

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

label {
    display: block;
    margin-bottom: 8px;
    font-weight: bold;
    color: var(--dark-bg);
}

input, textarea {
    width: 100%;
    padding: 15px;
    border: 1px solid #cccccc;
    border-radius: 5px;
    font-family: inherit;
    font-size: 1rem;
    transition: border-color 0.3s;
}

input:focus, textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.submit-button {
    width: 100%;
}

/* Footer */
footer {
    background-color: var(--dark-bg);
    color: #ffffff;
    text-align: center;
    padding: 40px 0;
    font-size: 0.9rem;
}

footer p {
    margin-bottom: 8px;
    opacity: 0.8;
}

/* Animations (Fade-in on Scroll) */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(50px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

/* JavaScript에서 추가될 클래스 */
.animate-on-scroll.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive Design */
@media (max-width: 768px) {
    /* 모바일 환경에서 헤더 높이 재조정 (Sticky 유지) */
    :root {
        --header-height: 60px;
    }

    .logo {
        font-size: 1.5rem;
    }

    nav ul li {
        margin-left: 15px;
    }
    
    nav ul li a {
        font-size: 0.9rem;
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }
    
    .hero-content p {
        font-size: 1.2rem;
    }

    .about-content {
        flex-direction: column;
    }
    
    .section {
        padding: 60px 0;
    }
}