:root {
    --bg-purple: #dde9f2;
    --container-dark: #1E1E1E;
    --card-dark: #2A2A2A;
    --card-light-dark: #3A3A3A;
    --coral: #d63543;
    --yellow: #FFD93D;
    --white: #FFFFFF;
    --text-dark: #121212;
    --text-gray: #A0A0A0;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Inter', 'Noto Sans KR', sans-serif;
}

html,
body {
    overflow-x: clip;
    width: 100%;
    margin: 0;
    padding: 0;
}

body {
    background-color: black;
    display: flex;
    justify-content: center;
    align-items: flex-start;
}

/* Main App Container */
.app-container {
    background-color: var(--container-dark);
    width: 100%;
    max-width: 1400px;
    border-radius: 40px;
    padding: 30px;
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.3);
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* =========================================
   Top Navigation (네비게이션 바)
   ========================================= */
.navbar {
    background-color: var(--white);
    border-radius: 50px;
    padding: 15px 30px 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    
    min-width: auto; 
    position: sticky;
    top: 20px;
    z-index: 9999;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    
    transition: all 0.4s cubic-bezier(0.25, 1, 0.5, 1);
    
    margin-left: auto;
    margin-right: 0;
    width: 100%;
    box-sizing: border-box;
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.85); 
    backdrop-filter: blur(10px);
    box-shadow: 0 8px 24px rgba(0,0,0,.12);
    width: max-content; 
    padding: 10px 15px; 
}

.nav-brand {
    font-weight: 800;
    font-size: 1.2rem;
    color: var(--text-dark);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
    
    transition: all 0.4s cubic-bezier(0.25, 1, 0.5, 1);
    opacity: 1;
    overflow: hidden;
    white-space: nowrap;
    max-width: 300px;
}

.nav-links {
    display: flex;          
    align-items: center;
    gap: 30px;
    list-style: none;
    margin: 0;
    padding: 0;
    
    transition: all 0.4s cubic-bezier(0.25, 1, 0.5, 1);
    opacity: 1;
    overflow: hidden;
    white-space: nowrap;    
    max-width: 800px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 600;
    font-size: 0.9rem;
    text-transform: uppercase;
}

.navbar.scrolled .nav-brand,
.navbar.scrolled .nav-links {
    opacity: 0;
    max-width: 0;
    margin: 0;
    padding: 0;
    border: none;
    gap: 0; 
}

.nav-actions {
    display: flex;
    align-items: center; 
    gap: 10px;
    white-space: nowrap; 
}

.btn-nav-outline {
    background: transparent;
    border: 2px solid #E0E0E0;
    padding: 10px 20px;
    border-radius: 30px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    color: var(--text-dark);
    
    /* [복구] 버튼 글자 수직 중앙 정렬 */
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.btn-nav-solid {
    background: var(--text-dark);
    color: var(--white);
    /* [복구] 옆 버튼과 높이를 동일하게 맞추기 위한 투명 테두리 */
    border: 2px solid transparent; 
    padding: 10px 20px;
    border-radius: 30px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    
    /* [복구] 버튼 글자 수직 중앙 정렬 */
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

/* =========================================
   Main Grid Layout (누락되었던 좌우 분할 복구!)
   ========================================= */
.main-grid {
    display: grid;
    grid-template-columns: 1.2fr 1fr; /* 좌 1.2 : 우 1 비율 */
    gap: 20px;
    width: 100%;
}

/* Left Column */
.left-col {
    display: flex;
    flex-direction: column;
    gap: 20px;
    min-width: 0; 
}

/* Right Column (누락되었던 우측 컬럼 복구!) */
.right-col {
    display: flex;
    flex-direction: column;
    gap: 20px;
    min-width: 0;
}

/* =========================================
   Cards & Content Styles
   ========================================= */
.hero-card {
    background-color: var(--card-dark);
    border-radius: 30px;
    padding: 50px 40px;
    color: var(--white);
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: 20px;
    word-break: keep-all;
}

.hero-desc {
    color: var(--text-gray);
    font-size: 1.1rem;
    line-height: 1.6;
    max-width: 80%;
    margin-bottom: 20px;
}

.schedule-badge {
    display: inline-block;
    border: 1px solid var(--white);
    padding: 8px 20px;
    border-radius: 30px;
    font-weight: 600;
    margin-bottom: 15px;
    font-size: 0.9rem;
}

.action-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.action-box {
    border-radius: 20px;
    padding: 20px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    text-decoration: none;
    font-weight: 800;
    font-size: 1.2rem;
    transition: transform 0.2s;
}

.action-box:hover {
    transform: translateY(-2px);
}

.box-white {
    background-color: var(--white);
    color: var(--text-dark);
}

.box-dark {
    background-color: var(--card-light-dark);
    color: var(--white);
}

.info-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.zoom-card, .info-card {
    border-radius: 30px;
    padding: 30px;
    position: relative;
    min-height: 200px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    text-decoration: none;
    color: var(--text-dark);
    transition: transform 0.2s, background-color 0.2s, border-color 0.2s;
}

.zoom-card h3, .info-card h3 {
    font-size: 2rem;
    font-weight: 900;
    margin-top: auto;
}

.zoom-card p, .info-card p {
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 10px;
}

.zoom-card:hover {
    transform: translateY(-2px); 
}

.circle-arrow {
    width: 40px;
    height: 40px;
    background-color: var(--white);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    position: absolute;
    top: 25px;
    right: 25px;
    font-weight: bold;
    color: var(--text-dark);
}

.courses-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
}

.course-btn {
    background: var(--card-dark);
    border: 1px solid #555;
    color: white;
    padding: 12px;
    border-radius: 15px;
    text-align: center;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 600;
    transition: transform 0.2s, background-color 0.2s, border-color 0.2s;
}

.course-btn:hover {
    transform: translateY(-2px);
}

/* 링크 밑줄 제거 전용 클래스 */
.no-underline {
    text-decoration: none !important;
    color: inherit !important; 
}

/* =========================================
   Mobile Media Query (모바일 & 태블릿 반응형)
   ========================================= */
@media (max-width: 768px) { /* 태블릿 화면크기까지 커버하도록 768px로 조정 */
    body { padding: 10px; }
    
    .app-container { 
        padding: 15px; 
        border-radius: 20px; 
    }
    
    .navbar { 
        padding: 10px 15px; 
    }
    
    .nav-brand { 
        max-width: 140px; 
        height: auto; 
    }
    
    .nav-actions { 
        gap: 8px; 
    }
    
    .btn-nav-outline, .btn-nav-solid {
        padding: 8px 14px;
        font-size: 0.8rem;
        white-space: nowrap;
    }
    
    /* 모바일에서는 강제로 1줄로 나열되게 변경 */
    .main-grid { 
        grid-template-columns: 1fr; 
    }
    
    .action-row, .info-row {
        grid-template-columns: 1fr;
    }
}