/* --- Global Styles & Variables --- */
:root {
    --bg-color: #1a1a1d;
    --primary-text-color: #f5f5f5;
    --secondary-text-color: #c3c3c3;
    --accent-color: #4ecca3;
    --card-bg-color: #252528;
    --code-bg-color: #0d0d0f;
    --border-color: #3a3a3c;
}

body {
    margin: 0;
    padding: 0;
    font-family: 'Poppins', sans-serif;
    background-color: var(--bg-color);
    color: var(--primary-text-color);
    line-height: 1.7;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

h1, h2 {
    font-weight: 700;
    color: var(--primary-text-color);
    margin-bottom: 0.5em;
}

h1 {
    font-size: 2.8rem;
    line-height: 1.2;
}

h2 {
    font-size: 2rem;
    border-bottom: 2px solid var(--accent-color);
    padding-bottom: 10px;
    margin-top: 2.5em;
}

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

a:hover {
    color: #8affd4;
}

/* --- Header --- */
header {
    text-align: center;
    padding: 60px 20px;
    border-bottom: 1px solid var(--border-color);
}

.subtitle {
    font-size: 1.2rem;
    color: var(--secondary-text-color);
    max-width: 600px;
    margin: 1em auto 2em;
}

.cta-button {
    display: inline-block;
    background-color: var(--accent-color);
    color: var(--bg-color);
    padding: 15px 35px;
    border-radius: 5px;
    font-weight: 600;
    font-size: 1.1rem;
    text-transform: uppercase;
    transition: background-color 0.3s ease, transform 0.2s ease;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.cta-button:hover {
    background-color: #8affd4;
    transform: translateY(-3px);
}

/* --- Main Content Sections --- */
main {
    padding: 20px 0;
}

section {
    margin-bottom: 40px;
}

p {
    margin-bottom: 1em;
    color: var(--secondary-text-color);
}

.note {
    background-color: var(--card-bg-color);
    border-left: 4px solid var(--accent-color);
    padding: 15px 20px;
    margin-top: 20px;
    border-radius: 0 5px 5px 0;
    font-size: 0.95rem;
}

.note strong {
    color: var(--primary-text-color);
}

/* --- Code Block --- */
.code-block {
    background-color: var(--code-bg-color);
    border-radius: 8px;
    padding: 20px;
    border: 1px solid var(--border-color);
    margin: 2em 0;
}

.code-block p {
    color: #888;
    font-family: 'Courier New', Courier, monospace;
    margin: 0 0 5px 0;
    font-size: 0.9em;
}

pre {
    margin: 0 0 15px 0;
    padding: 15px;
    background-color: #2c2c2f;
    border-radius: 5px;
    overflow-x: auto;
    white-space: pre-wrap;
    word-wrap: break-word;
}

code {
    font-family: 'Courier New', Courier, monospace;
    color: #a9d1ff; /* Light blue for code */
    font-size: 1rem;
}

/* --- Responsive Video --- */
.video-container {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 aspect ratio */
    height: 0;
    overflow: hidden;
    max-width: 100%;
    background: #000;
    border-radius: 8px;
    margin-top: 2em;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.3);
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 0;
}

/* --- Footer --- */
footer {
    text-align: center;
    padding: 40px 20px;
    margin-top: 40px;
    border-top: 1px solid var(--border-color);
    color: var(--secondary-text-color);
    font-size: 0.9rem;
}

footer p {
    margin: 0.5em 0;
}

/* --- Media Queries for Responsiveness --- */
@media (max-width: 768px) {
    h1 {
        font-size: 2.2rem;
    }
    h2 {
        font-size: 1.8rem;
    }
    .container {
        padding: 15px;
    }
    header {
        padding: 40px 10px;
    }
}