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

:root {
    --indigo: #2e3a59;
    --indigo-light: #4a5f8f;
    --indigo-dark: #1a2332;
}

[data-theme="light"] {
    --text: #2d3748;
    --text-light: #4a5568;
    --border: #e2e8f0;
    --bg: #ffffff;
}

[data-theme="dark"] {
    --text: #e2e8f0;
    --text-light: #cbd5e0;
    --border: #2d3748;
    --bg: #1a202c;
    --indigo: #6b8dd6;
    --indigo-light: #8ba9e0;
    --indigo-dark: #e2e8f0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Inter', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.7;
    color: var(--text);
    background: var(--bg);
    padding: 0;
    margin: 0;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.theme-toggle {
    position: fixed;
    top: 30px;
    right: 30px;
    background: transparent;
    border: 1px solid var(--border);
    border-radius: 8px;
    width: 44px;
    height: 44px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    color: var(--text);
    z-index: 100;
}

.theme-toggle:hover {
    background: var(--indigo);
    color: var(--bg);
    border-color: var(--indigo);
}

[data-theme="dark"] .sun-icon {
    display: none;
}

[data-theme="light"] .moon-icon {
    display: none;
}

[data-theme="dark"] .moon-icon {
    display: block;
}

[data-theme="light"] .sun-icon {
    display: block;
}

.container {
    max-width: 720px;
    margin: 0 auto;
    padding: 80px 40px 120px;
}

header {
    margin-bottom: 80px;
}

h1 {
    font-size: 2.5em;
    margin-bottom: 8px;
    color: var(--indigo-dark);
    font-weight: 700;
    letter-spacing: -0.5px;
    transition: color 0.3s ease;
}

.tagline {
    font-size: 1.15em;
    color: var(--text-light);
    font-weight: 400;
    transition: color 0.3s ease;
}

section {
    margin-bottom: 80px;
}

h2 {
    font-size: 1.5em;
    margin-bottom: 24px;
    color: var(--indigo);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 12px;
    transition: color 0.3s ease;
}

h2::before {
    content: '';
    width: 4px;
    height: 24px;
    background: var(--indigo);
    border-radius: 2px;
    transition: background 0.3s ease;
}

.hero {
    margin-bottom: 100px;
}

.lead {
    font-size: 1.35em;
    font-weight: 500;
    color: var(--indigo-dark);
    line-height: 1.5;
    margin-bottom: 20px;
    transition: color 0.3s ease;
}

section p {
    color: var(--text-light);
    font-size: 1.05em;
    line-height: 1.8;
    margin-bottom: 20px;
    transition: color 0.3s ease;
}

.contact {
    margin-top: 100px;
    padding-top: 60px;
    border-top: 1px solid var(--border);
    transition: border-color 0.3s ease;
}

.links {
    display: flex;
    gap: 16px;
    margin-top: 24px;
}

.links a {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--indigo);
    text-decoration: none;
    padding: 12px 24px;
    border: 1px solid var(--indigo);
    border-radius: 6px;
    transition: all 0.2s ease;
    font-weight: 500;
    font-size: 0.95em;
}

.links a:hover {
    background: var(--indigo);
    color: white;
}

footer {
    text-align: center;
    margin-top: 100px;
    padding-top: 40px;
    border-top: 1px solid var(--border);
    color: var(--text-light);
    font-size: 0.9em;
    transition: border-color 0.3s ease, color 0.3s ease;
}

@media (max-width: 768px) {
    .container {
        padding: 60px 24px 80px;
    }

    .theme-toggle {
        top: 20px;
        right: 20px;
        width: 40px;
        height: 40px;
    }

    h1 {
        font-size: 2em;
    }

    h2 {
        font-size: 1.3em;
    }

    .lead {
        font-size: 1.2em;
    }

    section {
        margin-bottom: 60px;
    }

    .links {
        flex-direction: column;
    }

    .links a {
        justify-content: center;
    }
}