:root {
    --background-color: #f8f8f8;
    --text-color: #333;
    --highlight-color: #000;
    --secondary-text-color: #888;
    --card-border-color: #e0e0e0;
    --alert-bg-color: #fff5f5;
    --alert-border-color: #e53e3e;
}

body {
    font-family: 'Pretendard', sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    margin: 0;
}

.guide-page {
    padding: 0 20px;
}

a {
    text-decoration: none;
    color: inherit;
}

ul, dl {
    list-style: none;
    margin: 0;
    padding: 0;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 40px;
    background-color: white;
    border-bottom: 1px solid var(--card-border-color);
}

.logo a {
    font-size: 24px;
    font-weight: bold;
    color: var(--highlight-color);
}

nav ul {
    display: flex;
    gap: 40px;
}

nav a {
    font-size: 16px;
    color: var(--text-color);
}

nav a.active {
    font-weight: bold;
}

.icons {
    display: flex;
    gap: 20px;
}

.icons img {
    width: 20px;
    height: 20px;
}

main {
    padding: 40px;
}

.hero {
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: 80px;
    margin-bottom: 80px;
    background-color: white;
    padding: 60px;
}

.hero-text .lead {
    font-size: 36px;
    color: var(--secondary-text-color);
    margin: 0;
}

.hero-text h1 {
    font-size: 96px;
    font-weight: bold;
    margin: 0;
    line-height: 1;
    color: var(--secondary-text-color);
}

.hero-text .highlight {
    color: var(--highlight-color);
}

.hero-text p:last-child {
    font-size: 18px;
    margin-top: 20px;
}

.hero-image {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
}

/* Slideshow */
.slideshow-container {
    position: relative;
    height: 400px; /* Adjust as needed */
}

.slideshow-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: contain; /* or 'cover' */
    opacity: 0;
    transition: opacity 1s ease-in-out;
}

.slideshow-image.active {
    opacity: 1;
}

.features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    text-align: left;
}

.feature-card {
    background-color: white;
    padding: 30px;
    border: 1px solid var(--card-border-color);
    border-radius: 8px;
    display: flex;
    flex-direction: column;
}

.feature-card h2 {
    font-size: 20px;
    margin: 0 0 10px 0;
}

.feature-card h2 span {
    color: var(--secondary-text-color);
    display: block;
    font-size: 16px;
    margin-bottom: 5px;
}

.feature-card p {
    margin: 0;
    color: var(--secondary-text-color);
    flex-grow: 1;
}

.feature-card a {
    font-size: 24px;
    margin-top: 20px;
    align-self: flex-end;
}

/* Guide Page Styles */
.guide-container {
    display: grid;
    grid-template-columns: 200px 1fr;
    gap: 60px;
    padding: 40px;
    max-width: 1200px;
    margin: 0 auto;
}

.sub-nav {
    position: sticky;
    top: 40px;
    height: fit-content;
}

.sub-nav ul {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.sub-nav a {
    font-size: 16px;
    color: var(--secondary-text-color);
}

.sub-nav a.active {
    font-weight: bold;
    color: var(--highlight-color);
}

.guide-content section {
    margin-bottom: 80px;
    scroll-margin-top: 40px; /* Offset for sticky nav */
}

.guide-content h2 {
    font-size: 32px;
    margin-bottom: 20px;
}

.guide-content > p {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-color);
}

.definition-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
}

.definition-text p {
    margin-bottom: 20px; /* Add space between paragraphs */
}

.definition-text p:last-child {
    margin-bottom: 0;
}

.definition-image img {
    width: 100%;
    border-radius: 8px;
}

.guide-content .content-block {
    background-color: white;
    padding: 25px;
    border-radius: 8px;
    margin-bottom: 20px;
    border: 1px solid var(--card-border-color);
}

.guide-content .content-block h3 {
    font-size: 20px;
    margin: 0 0 10px 0;
}

.guide-content .alert-block {
    background-color: var(--alert-bg-color);
    border-left: 5px solid var(--alert-border-color);
}

.guide-content .alert-block ul {
    list-style-type: disc;
    padding-left: 20px;
    margin-top: 15px;
}

.guide-content .alert-block li {
    margin-bottom: 10px;
}

.guide-content .concentration-list {
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.guide-content .concentration-list dt {
    font-size: 20px;
    font-weight: bold;
    color: var(--highlight-color);
    margin-bottom: 5px;
}

.guide-content .concentration-list dd {
    margin-left: 0;
    padding-left: 20px;
    border-left: 3px solid var(--card-border-color);
}

.guide-content .concentration-list dd strong {
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
    font-weight: normal;
    color: var(--secondary-text-color);
}

.guide-content .concentration-list dd p {
    margin: 0;
    font-size: 15px;
    line-height: 1.7;
}