@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
    --deep-slate: #1E293B;
    --tech-blue: #3B82F6;
    --bg-gray: #F8FAFC;
    --border-gray: #E2E8F0;
    --text-main: #334155;
    --text-muted: #64748B;
    --white: #ffffff;
}

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

body {
    font-family: 'Inter', sans-serif;
    color: var(--text-main);
    background-color: var(--bg-gray);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    background-color: var(--white);
    border-bottom: 1px solid var(--border-gray);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--deep-slate);
    text-decoration: none;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 1.5rem;
}

nav a {
    text-decoration: none;
    color: var(--text-muted);
    font-weight: 500;
    font-size: 0.875rem;
    transition: color 0.2s;
}

nav a:hover {
    color: var(--tech-blue);
}

.btn-primary {
    background-color: var(--tech-blue);
    color: var(--white);
    padding: 0.5rem 1rem;
    border-radius: 0.375rem;
    font-weight: 500;
    text-decoration: none;
    font-size: 0.875rem;
    transition: background-color 0.2s;
}

.btn-primary:hover {
    background-color: #2563EB;
}

.container {
    display: flex;
    flex: 1;
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
}

aside {
    width: 280px;
    border-right: 1px solid var(--border-gray);
    padding: 2rem;
    background-color: var(--white);
    height: calc(100vh - 64px);
    position: sticky;
    top: 64px;
    overflow-y: auto;
}

aside h3 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: 1rem;
}

aside ul {
    list-style: none;
    margin-bottom: 2rem;
}

aside li {
    margin-bottom: 0.5rem;
}

aside a {
    text-decoration: none;
    color: var(--text-main);
    font-size: 0.875rem;
    display: block;
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    transition: all 0.2s;
}

aside a:hover {
    background-color: #F1F5F9;
    color: var(--tech-blue);
}

aside a.active {
    background-color: #EFF6FF;
    color: var(--tech-blue);
    font-weight: 600;
}

main {
    flex: 1;
    padding: 3rem;
    max-width: 900px;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 800;
    color: var(--deep-slate);
    margin-bottom: 1.5rem;
}

.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.card {
    background: var(--white);
    border: 1px solid var(--border-gray);
    padding: 1.5rem;
    border-radius: 0.5rem;
    box-shadow: 0 1px 2px rgba(0,0,0,0.05);
}

.card h4 {
    margin-bottom: 0.5rem;
    color: var(--deep-slate);
}

.card p {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.code-block {
    background-color: var(--deep-slate);
    color: #E2E8F0;
    padding: 1.25rem;
    border-radius: 0.5rem;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.875rem;
    margin: 1.5rem 0;
    overflow-x: auto;
}

footer {
    border-top: 1px solid var(--border-gray);
    padding: 2rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
    background-color: var(--white);
}

.grid-contacts {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
    margin-top: 2rem;
}

@media (max-width: 768px) {
    .container {
        flex-direction: column;
    }
    aside {
        width: 100%;
        height: auto;
        position: static;
        border-right: none;
        border-bottom: 1px solid var(--border-gray);
    }
    main {
        padding: 1.5rem;
    }
}