/* 기본 공통 설정 */
* { 
    margin: 0; 
    padding: 0; 
    box-sizing: border-box; 
}

body { 
    font-family: 'Montserrat', 'Noto Sans KR', sans-serif; 
    line-height: 1.8; 
    color: #333; 
    background-color: #fff; 
}

/* 네비게이션 */
nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 10%;
    background: #fff;
    border-bottom: 1px solid #eee;
    position: sticky;  
    top: 0;            
    z-index: 1000;
}

.logo a {
    font-size: 1.3rem;
    font-weight: bold;
    text-decoration: none;
    color: #7d7dff;
}

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

nav ul li {
    margin-left: 2rem;
}

nav ul li a {
    text-decoration: none;
    color: #888;
}

nav ul li a:hover {
    color: #7d7dff;
}

/* 헤더 영역 */
.dual-header { 
    background: linear-gradient(135deg, #b0bfff 0%, #d1d9ff 100%); 
    padding: 100px 0 120px; 
    text-align: center; 
}

.header-title h1 { 
    font-size: 3.5rem; 
    color: #fff; 
    margin-bottom: 15px; 
}

.tag { 
    display: inline-block; 
    padding: 6px 18px; 
    background: rgba(255,255,255,0.2); 
    color: #fff; 
    border-radius: 25px; 
    font-size: 0.9rem; 
    border: 1px solid #fff; 
}

.profile-container { 
    display: flex; 
    justify-content: center; 
    gap: 40px; 
    margin-top: 60px; 
}

.profile-item { 
    flex: 0 1 450px; 
} 

/* 책 표지 */
.book-cover { 
    width: 100%; 
    aspect-ratio: 2 / 3; 
    border-radius: 15px !important; 
    border: 6px solid #fff; 
    overflow: hidden; 
    box-shadow: 0 30px 60px rgba(0,0,0,0.25); 
    margin-bottom: 30px; 
}

.book-cover img { 
    width: 100%; 
    height: 100%; 
    object-fit: cover; 
}

.version-label { 
    display: block; 
    font-weight: bold; 
    font-size: 1rem; 
    color: #7d7dff; 
    background: #fff; 
    padding: 10px 0; 
    border-radius: 40px; 
    width: 220px; 
    margin: 0 auto 20px; 
}

.version-desc { 
    color: rgba(255, 255, 255, 0.95); 
    font-size: 1.15rem; 
}

/* 타이틀 얇고 긴 선 */
.underlined-title { 
    text-align: center; 
    position: relative; 
    padding-bottom: 25px; 
    margin-bottom: 45px; 
}

.underlined-title::after { 
    content: ''; 
    position: absolute; 
    bottom: 0; 
    left: 50%; 
    transform: translateX(-50%); 
    width: 300px; 
    height: 1px; 
    background: rgba(43, 216, 202, 0.6); 
}

/* 본문 레이아웃 */
.container { 
    max-width: 1100px;
    margin: 5rem auto; 
    padding: 0; 
}

h2 { 
    font-size: 2.5rem; 
    color: rgb(43, 216, 202); 
}

.center-title { 
    text-align: center; 
    padding: 0 20px; 
}

.intro-content p { 
    max-width: 850px; 
    margin: 0 auto 30px; 
    color: #555; 
    font-size: 1.1rem; 
    text-align: justify; 
    word-break: keep-all; 
    line-height: 1.9;
}

/* 목차 섹션 스타일 */
.contents-list-section {
    margin: 100px 0;
}

.contents-box {
    max-width: 700px;
    margin: 0 auto;
    background: #fff;
    padding: 40px;
    border-radius: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.03);
    border: 1px solid #f0f0f0;
}

.book-contents {
    list-style: none;
    text-align: left;
}

.book-contents li {
    padding: 15px 0;
    border-bottom: 1px dashed #eee;
    font-size: 1.1rem;
    color: #555;
    display: flex;
    align-items: center;
}

.book-contents li:last-child {
    border-bottom: none;
}

.book-contents li span {
    font-weight: bold;
    color: #7d7dff;
    margin-right: 20px;
    font-size: 0.9rem;
    text-transform: uppercase;
}

/* 인용 박스 스타일링 */
.personality-box { 
    background: #f8f9ff; 
    padding: 80px 40px; 
    border-radius: 50px; 
    margin: 80px 20px; 
    text-align: center; 
}

.tag-container { 
    display: flex; 
    justify-content: center; 
    gap: 20px; 
    margin-bottom: 30px; 
}

.personality-text { 
    color: #666; 
    font-style: italic; 
    font-size: 1.2rem; 
    max-width: 750px; 
    margin: 0 auto; 
    line-height: 1.8; 
}

/* 도서 구매 버튼 */
.buy-button-wrapper { 
    margin-top: 50px; 
}
.buy-button { 
    display: inline-block; 
    padding: 18px 50px; 
    background-color: #7d7dff; 
    color: #fff; 
    text-decoration: none; 
    font-weight: bold; 
    font-size: 1.1rem; 
    border-radius: 60px; 
    transition: all 0.3s ease; 
    box-shadow: 0 10px 20px rgba(125, 125, 255, 0.2); 
}

.buy-button:hover { 
    background-color: #6a6aff; 
    transform: translateY(-5px); 
    box-shadow: 0 15px 30px rgba(125, 125, 255, 0.3); 
}

.mid-banner { 
    text-align: center; 
    padding: 60px 0; 
    word-spacing: 5px;
    opacity: 0.8;
}

footer {
    background-color: rgb(98, 205, 212);
    text-align: center;
    color: white;
    padding: 50px;
}

footer a {
    color:white;
}

footer a:hover {
    opacity: 0.5;
    background-color: transparent;
}