:root {
    --bg: #ffffff;
    --text: #111111;
    --muted: #666666;
    --border: #dddddd;
}

body.dark {
    --bg: #111111;
    --text: #f5f5f5;
    --muted: #aaaaaa;
    --border: #333333;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: Inter, Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    transition: background 0.2s ease, color 0.2s ease;
}

.top-nav {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.top-nav a {
    color: var(--text);
    text-decoration: none;
    font-weight: 600;
}

.top-nav a:hover {
    text-decoration: underline;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
}

.title-group {
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
}

h1 {
    margin: 0;
    font-size: 2.5rem;
    font-weight: 900;
    letter-spacing: -0.04em;
    line-height: 1;
}

.subtitle {
    margin: 0;
    font-size: 1.2rem;
    font-weight: 700;
}

.layout {
    display: flex;
    gap: 3rem;
}

.content {
    flex: 1;
    max-width: none;
}

.content ul {
    margin-top: 2rem;
    padding-left: 2rem;
}

.content li {
    margin-bottom: 2rem;
    line-height: 1.8;
}

.content li a {
    display: inline-block;
    font-size: 1.1rem;
    line-height: 1.6;
}

main {
    padding: 1.5rem 0;
}

.content section:first-child h2 {
    margin-top: 0;
}

.content h2 {
    font-size: 3rem;
    font-weight: 900;
    letter-spacing: -0.04em;
    line-height: 1.1;
    border-bottom: 3px solid currentColor;
    padding-bottom: 0.5rem;
    margin-top: 4rem;
    margin-bottom: 1.5rem;
}

.content h3 {
    font-size: 1.7rem;
    font-weight: 800;
    margin-top: 2.5rem;
    margin-bottom: 1rem;
}

.statement {
    font-size: 2rem;
    font-weight: 800;
}

p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--muted);
    margin: 0 0 1.25rem;
}

section {
    scroll-margin-top: 90px;
}

button {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text);
    padding: 0.5rem 0.9rem;
    cursor: pointer;
    font-size: 0.9rem;
}

button:hover {
    opacity: 0.8;
}

footer {
    border-top: 1px solid var(--border);
    padding: 1.5rem 0;
    margin-top: 3rem;
    font-size: 0.9rem;
    color: var(--muted);
}

@media (max-width: 800px) {

    .container {
        padding: 0.5rem 1rem;
    }

    .top-nav {
        width: 100%;
        flex-wrap: wrap;
    }

    .site-header {
        position: sticky;
        padding: 0.5rem 0;
        gap: 0.75rem;
    }

    h1 {
        font-size: 1.8rem;
    }

    .subtitle {
        font-size: 1rem;
    }

    .content h2 {
        font-size: 2.2rem;
        margin-top: 2.5rem;
    }

    .content h3 {
        font-size: 1.4rem;
    }

    main {
        padding: 0.5rem 0;
    }

    p {
        font-size: 1rem;
        line-height: 1.7;
    }
}