/* ===================================
   우아하고 고급스러운 디자인 시스템
   =================================== */

/* Google Fonts - 세련된 폰트 */
@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+KR:wght@300;400;500;600;700&family=Noto+Sans+KR:wght@300;400;500;600;700&display=swap');

/* 색상 팔레트 */
:root {
    /* 고급스러운 네이비 & 골드 */
    --primary-dark: #1a2332;
    --primary-navy: #2d3e50;
    --primary-blue: #4a6fa5;
    --accent-gold: #d4af37;
    --accent-rose: #c49a6c;
    
    /* 우아한 중성색 */
    --elegant-white: #faf8f5;
    --soft-cream: #f5f1eb;
    --warm-gray: #8b8680;
    --deep-charcoal: #3a3a3a;
    
    /* 세련된 액센트 */
    --sage-green: #b5c4a1;
    --dusty-rose: #d4a5a5;
    --powder-blue: #a8c8e1;
    
    /* 그림자 */
    --shadow-soft: 0 4px 20px rgba(26, 35, 50, 0.08);
    --shadow-medium: 0 8px 30px rgba(26, 35, 50, 0.12);
    --shadow-strong: 0 12px 40px rgba(26, 35, 50, 0.15);
}

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

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: #ffffff;
    color: #333333;
    line-height: 1.85;
    font-size: 17px;
    letter-spacing: -0.01em;
    min-height: 100vh;
}

/* 헤더 - 고급스러운 디자인 */
header {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-navy) 100%);
    padding: 25px 40px;
    box-shadow: var(--shadow-medium);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 2px solid var(--accent-gold);
}

header h1 {
    font-family: 'Noto Serif KR', serif;
    color: var(--elegant-white);
    margin: 15px 0;
    font-size: 2.2em;
    font-weight: 600;
    letter-spacing: 0.02em;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

header h1 a {
    color: var(--elegant-white);
    text-decoration: none;
    transition: all 0.3s ease;
    display: inline-block;
}

header h1 a:hover {
    color: var(--accent-gold);
    transform: translateY(-2px);
}

/* 네비게이션 - 세련된 메뉴 */
nav {
    margin-top: 20px;
}

nav ul {
    list-style: none;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px;
}

nav ul li {
    display: inline-block;
}

nav a {
    text-decoration: none;
    color: var(--elegant-white);
    font-weight: 500;
    font-size: 1.05em;
    padding: 10px 24px;
    border-radius: 25px;
    transition: all 0.3s ease;
    background: rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

nav a:hover {
    background: var(--accent-gold);
    color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(212, 175, 55, 0.4);
}

/* 메인 컨텐츠 */
main {
    padding: 60px 30px;
    max-width: 1000px;
    margin: 0 auto;
    background: #ffffff;
}

.week-content {
    background: #ffffff;
    padding: 50px;
    border-radius: 20px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    margin-bottom: 40px;
    border: 1px solid #f0f0f0;
}

/* 제목 스타일 */
.week-content h2,
.major h2 {
    font-family: 'Noto Serif KR', serif;
    color: #2d3e50;
    border-bottom: 3px solid var(--accent-gold);
    padding-bottom: 20px;
    margin-bottom: 40px;
    font-size: 2.5em;
    font-weight: 600;
    letter-spacing: -0.02em;
    position: relative;
}

.week-content h2::after {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 0;
    width: 120px;
    height: 3px;
    background: var(--accent-rose);
}

.week-content h3 {
    font-family: 'Noto Serif KR', serif;
    color: #4a6fa5;
    margin: 45px 0 25px 0;
    font-size: 1.9em;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 12px;
}

.week-content h3::before {
    content: '✦';
    color: var(--accent-gold);
    font-size: 0.8em;
}

.week-content h4 {
    color: #2d3e50;
    margin: 30px 0 18px 0;
    font-size: 1.4em;
    font-weight: 600;
}

/* 우아한 박스 디자인 */
.learning-objectives {
    background: linear-gradient(135deg, #f0f7ff 0%, #e6f2ff 100%);
    padding: 35px;
    border-left: 5px solid var(--primary-blue);
    margin: 30px 0;
    border-radius: 15px;
    box-shadow: var(--shadow-soft);
}

.learning-objectives h3 {
    color: var(--primary-blue);
    margin-top: 0;
    font-size: 1.6em;
}

.example-box {
    background: linear-gradient(135deg, #fafafa 0%, #f5f5f5 100%);
    padding: 28px;
    border-left: 4px solid var(--sage-green);
    margin: 25px 0;
    border-radius: 12px;
    box-shadow: var(--shadow-soft);
}

.example-box blockquote {
    margin: 15px 0;
    padding: 18px;
    background: white;
    border-left: 4px solid var(--warm-gray);
    font-style: italic;
    border-radius: 8px;
    color: #555555;
    line-height: 1.9;
}

.note-box {
    background: linear-gradient(135deg, #fffaf0 0%, #fff8e7 100%);
    padding: 28px;
    border-left: 5px solid var(--accent-gold);
    margin: 25px 0;
    border-radius: 12px;
    box-shadow: var(--shadow-soft);
    position: relative;
}

.note-box::before {
    content: '💡';
    position: absolute;
    top: -15px;
    left: 20px;
    font-size: 2em;
    background: white;
    padding: 5px 10px;
    border-radius: 50%;
    box-shadow: var(--shadow-soft);
}

.warning-box, .danger-box {
    background: linear-gradient(135deg, #fff5f5 0%, #ffe5e5 100%);
    padding: 28px;
    border-left: 5px solid var(--dusty-rose);
    margin: 25px 0;
    border-radius: 12px;
    box-shadow: var(--shadow-soft);
}

/* 비교 박스 */
.comparison-box {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
    margin: 30px 0;
}

.bad-example, .good-example {
    padding: 28px;
    border-radius: 15px;
    box-shadow: var(--shadow-soft);
    position: relative;
    overflow: hidden;
}

.bad-example {
    background: linear-gradient(135deg, #fff5f5 0%, #ffecec 100%);
    border: 2px solid #ffb3b3;
}

.bad-example::before {
    content: '❌';
    position: absolute;
    top: 15px;
    right: 15px;
    font-size: 2em;
    opacity: 0.3;
}

.good-example {
    background: linear-gradient(135deg, #f0fff0 0%, #e6ffe6 100%);
    border: 2px solid var(--sage-green);
}

.good-example::before {
    content: '✅';
    position: absolute;
    top: 15px;
    right: 15px;
    font-size: 2em;
    opacity: 0.3;
}

/* 네비게이션 버튼 */
.navigation-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin: 60px 0 30px 0;
    flex-wrap: wrap;
}

.btn {
    display: inline-block;
    padding: 16px 40px;
    text-decoration: none;
    border-radius: 30px;
    font-weight: 600;
    font-size: 1.05em;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-soft);
    letter-spacing: 0.02em;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--primary-navy) 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-strong);
    background: linear-gradient(135deg, var(--primary-navy) 0%, var(--primary-dark) 100%);
}

.btn-secondary {
    background: linear-gradient(135deg, var(--warm-gray) 0%, #6d6d6d 100%);
    color: white;
}

.btn-secondary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-strong);
}

/* 리스트 스타일 */
ul, ol {
    margin: 20px 0;
    padding-left: 35px;
    color: #333333;
}

li {
    margin: 12px 0;
    line-height: 1.85;
    color: #333333;
}

ul li::marker {
    color: var(--accent-gold);
    font-size: 1.2em;
}

/* 문단 스타일 */
p {
    color: #333333;
    margin: 15px 0;
    line-height: 1.85;
}

strong, b {
    color: #2d3e50;
    font-weight: 600;
}

a {
    color: #4a6fa5;
    text-decoration: none;
    transition: all 0.3s ease;
}

a:hover {
    color: var(--accent-gold);
}

/* 특별한 컨텐츠 */
.celebration-box {
    background: linear-gradient(135deg, var(--primary-navy) 0%, var(--primary-blue) 100%);
    color: white;
    padding: 50px;
    text-align: center;
    border-radius: 20px;
    margin: 50px 0;
    box-shadow: var(--shadow-strong);
    position: relative;
    overflow: hidden;
}

.celebration-box::before {
    content: '✨';
    position: absolute;
    font-size: 10em;
    top: -30px;
    right: -30px;
    opacity: 0.1;
}

.celebration-box h2 {
    color: white;
    font-size: 2.5em;
    margin-bottom: 20px;
    border: none;
}

/* 푸터 */
footer {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-navy) 100%);
    color: var(--elegant-white);
    text-align: center;
    padding: 40px 20px;
    margin-top: 80px;
    border-top: 3px solid var(--accent-gold);
}

footer p {
    margin: 10px 0;
    font-size: 0.95em;
    opacity: 0.9;
}

/* Week 리스트 스타일 */
.week-list {
    background: white;
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    border: 1px solid #f0f0f0;
}

.week-list h3 {
    font-family: 'Noto Serif KR', serif;
    margin: 30px 0 15px 0;
    font-size: 1.6em;
}

.week-list h3 a {
    color: #2d3e50;
    text-decoration: none;
    transition: all 0.3s ease;
    display: inline-block;
}

.week-list h3 a:hover {
    color: var(--accent-gold);
    transform: translateX(10px);
}

.week-list hr {
    border: none;
    border-top: 1px solid #e0e0e0;
    margin: 30px 0;
}

/* 반응형 디자인 */
@media (max-width: 768px) {
    header {
        padding: 20px 20px;
    }
    
    header h1 {
        font-size: 1.6em;
    }
    
    nav ul {
        gap: 5px;
    }
    
    nav a {
        font-size: 0.95em;
        padding: 8px 16px;
    }
    
    main {
        padding: 30px 15px;
    }
    
    .week-content {
        padding: 30px 20px;
    }
    
    .week-content h2 {
        font-size: 2em;
    }
    
    .week-content h3 {
        font-size: 1.5em;
    }
    
    .comparison-box {
        grid-template-columns: 1fr;
    }
    
    .navigation-buttons {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        text-align: center;
    }
}

/* ===================================
   포트폴리오 및 프로젝트 스타일
   =================================== */

.project-card {
    transition: all 0.3s ease;
}

.project-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 40px rgba(26, 35, 50, 0.15) !important;
}

main h2 {
    position: relative;
    display: inline-block;
    width: 100%;
}

main h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 120px;
    height: 3px;
    background: var(--accent-gold);
    border-radius: 2px;
}