:root {
    --primary-color: #7209b7;
    --secondary-color: #4361ee;
    --accent-color: #f72585;
    --light-color: #f8f9fa;
    --dark-color: #212529;
    --gray-color: #6c757d;
    --light-gray: #e9ecef;
    --success-color: #4cc9f0;
    --gradient: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans KR', sans-serif;
    line-height: 1.6;
    color: var(--dark-color);
    background-color: var(--light-color);
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 타이포그래피 */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 {
    font-size: 2.5rem;
}

h2 {
    font-size: 2rem;
    position: relative;
    display: inline-block;
}

h2:after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 50px;
    height: 4px;
    background: var(--accent-color);
    border-radius: 2px;
}

h3 {
    font-size: 1.5rem;
    color: var(--primary-color);
}

p {
    margin-bottom: 1rem;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: all 0.3s ease;
}

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

/* 헤더 */
header {
    background: var(--gradient);
    color: white;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

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

header h1 {
    margin: 0;
    font-size: 1.8rem;
}

/* 내비게이션 */
.nav-links {
    display: flex;
    list-style: none;
}

.nav-links li {
    margin-left: 1.5rem;
}

.nav-links a {
    color: white;
    font-weight: 500;
    position: relative;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--light-color);
}

.nav-links a:after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: white;
    transition: width 0.3s ease;
}

.nav-links a:hover:after, .nav-links a.active:after {
    width: 100%;
}

.hamburger {
    display: none;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background-color: white;
    margin: 5px 0;
    transition: all 0.3s ease;
    border-radius: 1px;
}

/* 히어로 섹션 */
.hero {
    background: var(--gradient);
    color: white;
    padding: 5rem 0;
    text-align: center;
}

.hero h2 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.btn {
    display: inline-block;
    padding: 0.8rem 1.5rem;
    background-color: var(--accent-color);
    color: white;
    border-radius: 5px;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: all 0.3s ease;
}

.btn:hover {
    background-color: var(--light-color);
    color: var(--accent-color);
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

/* 메인 컨텐츠 */
main {
    padding: 3rem 0;
}

.section {
    margin-top: 5rem;
	margin-bottom: 5rem;
}

.section h2 {
    margin-bottom: 2rem;
    text-align: center;
}

/* 소개 섹션 */
#intro .content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.timeline {
    position: relative;
    padding-left: 30px;
    border-left: 2px solid var(--light-gray);
}

.timeline-item {
    margin-bottom: 2rem;
    position: relative;
}

.timeline-year {
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.timeline-content {
    background-color: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.05);
}

.timeline-item:before {
    content: '';
    position: absolute;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--accent-color);
    left: -37px;
    top: 5px;
}

/* 원리 섹션 */
.cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.card {
    background-color: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
    text-align: center;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}

.card-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

/* 방법론 섹션 */
.methodology-container {
    max-width: 800px;
    margin: 0 auto;
}

.methodology-item {
    margin-bottom: 2rem;
    padding: 2rem;
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.05);
}

.cycle {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    margin: 1.5rem 0;
}

.cycle-step {
    background-color: var(--light-gray);
    padding: 0.8rem 1.2rem;
    border-radius: 5px;
    font-weight: 500;
    text-align: center;
    margin: 0.5rem 0;
}

.cycle-arrow {
    color: var(--primary-color);
    font-weight: bold;
    font-size: 1.5rem;
}

/* 고려사항 섹션 */
.considerations-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.consideration-item {
    background-color: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.05);
    border-left: 4px solid var(--accent-color);
}

.prompt-tips ul {
    margin-left: 1.5rem;
    margin-top: 1rem;
}

.prompt-tips li {
    margin-bottom: 0.8rem;
}

.comparison {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.comparison-item {
    padding: 1rem;
    border-radius: 8px;
    background-color: var(--light-gray);
}

@media (max-width: 768px) {
    .comparison {
        grid-template-columns: 1fr;
    }
}

/* CTA 섹션 */
.cta {
    background-color: var(--light-gray);
    padding: 3rem;
    border-radius: 10px;
    text-align: center;
    margin: 3rem 0;
}

.cta h2 {
    margin-bottom: 1rem;
}

.cta p {
    max-width: 600px;
    margin: 0 auto 2rem;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

/* 푸터 */
footer {
    background-color: var(--dark-color);
    color: white;
    padding: 2rem 0;
    text-align: center;
}

/* 반응형 */
@media (max-width: 992px) {
    h1 {
        font-size: 2.2rem;
    }
    
    h2 {
        font-size: 1.8rem;
    }
    
    h3 {
        font-size: 1.3rem;
    }
    
    .hero h2 {
        font-size: 2.5rem;
    }
    
    .hero p {
        font-size: 1.3rem;
    }
    
    #intro .content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: -1000%;
        left: 0;
        width: 100%;
        flex-direction: column;
        background: var(--primary-color);
        transition: top 0.5s ease;
        box-shadow: 0 5px 10px rgba(0, 0, 0, 0.1);
        padding: 2rem 0;
        text-align: center;
    }
    
    .nav-links.active {
        top: 60px;
    }
    
    .nav-links li {
        margin: 1rem 0;
    }
    
    .hamburger {
        display: block;
    }
    
    .hamburger.active .bar:nth-child(1) {
        transform: rotate(-45deg) translate(-5px, 6px);
    }
    
    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }
    
    .hamburger.active .bar:nth-child(3) {
        transform: rotate(45deg) translate(-5px, -6px);
    }
    
    .cycle {
        flex-direction: column;
    }
    
    .cycle-arrow {
        transform: rotate(90deg);
        margin: 0.5rem 0;
    }
}

@media (max-width: 576px) {
    .cards {
        grid-template-columns: 1fr;
    }
    
    .methodology-item {
        padding: 1.5rem;
    }
    
    .cta {
        padding: 2rem 1rem;
    }
}