/* 기본 초기화 및 폰트 설정 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: #1e293b;
    background-color: #f4f7fb; /* 화사하고 부드러운 배경 톤 */
    line-height: 1.6;
}

/* 상단 네비게이션 */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 2rem 5%;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    font-weight: 800;
    font-size: 1.3rem;
    letter-spacing: -0.5px;
    color: #1e3a8a;
}

nav a {
    text-decoration: none;
    color: #64748b;
    margin-left: 2rem;
    font-size: 0.95rem;
    transition: color 0.2s;
}

nav a:hover {
    color: #3b82f6;
}

.cta-btn {
    background: #3b82f6;
    color: #fff !important;
    padding: 0.6rem 1.2rem;
    border-radius: 6px;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.2);
}

/* 메인 히어로 섹션 */
.hero {
    text-align: center;
    padding: 8rem 5% 6rem;
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 2.8rem;
    font-weight: 800;
    letter-spacing: -1px;
    margin-bottom: 1.2rem;
    color: #0f172a;
}

.hero p {
    color: #475569;
    font-size: 1.1rem;
    margin-bottom: 2.5rem;
}

.primary-btn {
    display: inline-block;
    background: linear-gradient(135deg, #3b82f6, #8b5cf6); /* 블루와 퍼플이 부드럽게 어우러지는 그라데이션 */
    color: #fff;
    padding: 0.9rem 2.2rem;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
    transition: transform 0.2s;
}

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

/* 섹션 공통 */
.section {
    padding: 6rem 5%;
    max-width: 1000px;
    margin: 0 auto;
    text-align: center;
}

.section h2 {
    font-size: 2rem;
    margin-bottom: 3rem;
    letter-spacing: -0.5px;
    color: #0f172a;
}

/* 클래스 카드 그리드 */
.class-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    text-align: left;
}

.card {
    background: #ffffff;
    padding: 2.5rem;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.02);
    transition: transform 0.2s, box-shadow 0.2s;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 25px -5px rgba(59, 130, 246, 0.08);
}

.card h3 {
    margin-bottom: 0.8rem;
    font-size: 1.2rem;
    color: #1e3a8a;
}

.card p {
    color: #64748b;
    font-size: 0.95rem;
}

/* 연락처 섹션 */
.contact-section {
    border-top: 1px solid #e2e8f0;
}

.email-link {
    display: inline-block;
    margin-top: 1rem;
    font-size: 1.2rem;
    color: #3b82f6;
    font-weight: 600;
    text-decoration: underline;
}