:root {
    --bg-color: #ffffff;
    --text-color: #000000;
    --border-color: #000000;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #000000;
        --text-color: #ffffff;
        --border-color: #ffffff;
    }
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
    line-height: 1.6;
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 1rem;
    margin-bottom: 2rem;
    display: flex;
    justify-content: space-between;
    align-items: baseline;
}

header h1 {
    font-size: 2rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: -0.05em;
}

nav a {
    color: var(--text-color);
    text-decoration: none;
    margin-left: 1rem;
    font-weight: bold;
    text-transform: uppercase;
    font-size: 0.9rem;
}

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

main {
    flex: 1;
}

.hero {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    margin-bottom: 3rem;
}

@media (min-width: 600px) {
    .hero {
        flex-direction: row;
        align-items: center;
    }
}

.hero-text {
    flex: 1;
}

.hero-text h2 {
    font-size: 2.5rem;
    line-height: 1.1;
    margin-bottom: 1rem;
    letter-spacing: -0.02em;
}

.hero-text p {
    font-size: 1.2rem;
    margin-bottom: 1.5rem;
}

.cta {
    display: inline-block;
    border: 2px solid var(--border-color);
    padding: 0.75rem 1.5rem;
    text-decoration: none;
    color: var(--text-color);
    font-weight: bold;
    text-transform: uppercase;
    transition: all 0.2s;
}

.cta:hover {
    background-color: var(--text-color);
    color: var(--bg-color);
}

.hero-image {
    flex: 1;
    border: 2px solid var(--border-color);
    padding: 0.5rem;
}

.hero-image img {
    width: 100%;
    height: auto;
    display: block;
    filter: grayscale(100%);
    transition: filter 0.3s ease;
}

.hero-image img:hover {
    filter: grayscale(0%);
}

.features {
    border-top: 2px solid var(--border-color);
    padding-top: 2rem;
    margin-bottom: 3rem;
}

.features h3 {
    text-transform: uppercase;
    margin-bottom: 1rem;
}

.features ul {
    list-style-type: none;
}

.features li {
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
}

.features li:last-child {
    border-bottom: none;
}

.document-content h1 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
}

.document-content h2 {
    font-size: 1.5rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
}

.document-content p, .document-content ul {
    margin-bottom: 1rem;
}

.document-content ul {
    padding-left: 1.5rem;
}

footer {
    border-top: 2px solid var(--border-color);
    padding-top: 1rem;
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    text-transform: uppercase;
}

footer a {
    color: var(--text-color);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}