:root {
    --background-color: #3d3a36;
    --card-background-color: #f4f1ea;
    --text-color: #333;
    --primary-color: #8a6c4a;
    --primary-color-dark: #6f563a;
    --border-color: #ddd;
    --font-family: 'Pretendard', sans-serif;
    --shadow: 0 10px 20px rgba(0,0,0,0.19), 0 6px 6px rgba(0,0,0,0.23);
}

body {
    margin: 0;
    padding: 20px;
    font-family: var(--font-family);
    background-color: var(--background-color);
    background-image: url('https://www.transparenttextures.com/patterns/wood-pattern.png');
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 100vh;
    box-sizing: border-box;
}

header {
    width: 100%;
    max-width: 1200px;
    padding: 1rem 0;
    margin-bottom: 1.5rem;
    box-sizing: border-box;
}

header h1 {
    color: var(--card-background-color);
    text-align: center;
    margin: 0;
}

.site-wrapper {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 2rem;
    width: 100%;
    max-width: 1200px;
    align-items: start;
}

.main-content {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

main, article {
    width: 100%;
    box-sizing: border-box;
}

stock-calculator {
    display: block;
    background-color: var(--card-background-color);
    border-radius: 12px;
    box-shadow: var(--shadow);
    padding: 2rem;
    color: var(--text-color);
    transition: all 0.3s ease;
}

article {
    background-color: var(--card-background-color);
    border-radius: 12px;
    box-shadow: var(--shadow);
    padding: 1.5rem;
}

article h2 {
    color: var(--primary-color-dark);
    border-bottom: 2px solid var(--primary-color);
    padding-bottom: 0.5rem;
    margin-top: 0;
}

article p {
    line-height: 1.7;
    color: var(--text-color);
}

.sidebar {
    position: sticky;
    top: 20px;
}

footer {
    width: 100%;
    max-width: 1200px;
    box-sizing: border-box;
    text-align: center;
    padding: 1rem;
    margin-top: 2rem;
    font-size: 0.85rem;
    color: #ccc;
}

@media (max-width: 1024px) {
    .site-wrapper {
        grid-template-columns: 1fr;
    }
    .sidebar {
        position: static;
        margin-top: 1rem;
    }
}

@media (max-width: 600px) {
    body {
        padding: 10px;
    }
    header {
        margin-bottom: 1rem;
    }
    stock-calculator, article {
        padding: 1.5rem;
    }
}