@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@400;700&display=swap');

:root {
    --bg-color: #0d1117;
    --surface-color: #161b22;
    --primary-color: #21c3a8;
    --primary-hover-color: #2ad0b5;
    --text-color: #c9d1d9;
    --heading-color: #ffffff;
    --border-color: #30363d;
    --container-width: 960px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.7;
    font-size: 17px;
}

h1, h2 {
    font-weight: 700;
    color: var(--heading-color);
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

h1 {
    font-size: 3rem;
    color: var(--heading-color);
}

h2 {
    font-size: 2.4rem;
    padding-bottom: 0.5rem;
}

p, li {
    margin-bottom: 1rem;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    text-decoration: underline;
    color: var(--primary-hover-color);
}

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

header {
    background-color: rgba(13, 17, 23, 0.8);
    backdrop-filter: blur(10px);
    padding: 1.2rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--heading-color);
}

nav ul {
    list-style: none;
    display: flex;
    gap: 2rem;
}

nav a {
    font-weight: 400;
    font-size: 1rem;
    color: var(--text-color);
}

nav a:hover {
    color: var(--heading-color);
    text-decoration: none;
}

main section {
    padding: 5rem 0;
    border-bottom: 1px solid var(--border-color);
}

main section:last-of-type {
    border-bottom: none;
}

#main {
    text-align: center;
    padding-top: 6rem;
    padding-bottom: 6rem;
}

#main h1 {
    color: var(--primary-color);
}

.btn {
    display: inline-block;
    margin-top: 2rem;
    padding: 0.9rem 2.8rem;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--bg-color);
    background-color: var(--primary-color);
    border: 2px solid var(--primary-color);
    border-radius: 8px;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: all 0.3s ease;
}

.btn:hover {
    background-color: transparent;
    color: var(--primary-color);
    text-decoration: none;
    transform: translateY(-2px);
}

.highlight-box {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-left: 5px solid var(--primary-color);
    padding: 2rem;
    border-radius: 8px;
    margin-top: 2rem;
}

.highlight-box ul {
    list-style-type: '✓ ';
    padding-left: 1.5rem;
}

.highlight-box li {
    padding-left: 0.5rem;
}

ol {
    padding-left: 1.5rem;
}

code {
    background-color: var(--surface-color);
    color: var(--primary-color);
    padding: 0.2em 0.4em;
    border-radius: 4px;
    font-family: monospace;
}

footer {
    text-align: center;
    padding: 3rem 0;
    font-size: 0.9rem;
    color: #8b949e;
    border-top: 1px solid var(--border-color);
}