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

body {
    background: #000;
    color: #c4ccd6;
    font-family: system-ui, sans-serif;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 60px 22px 48px;
}

h1 {
    font-size: 2.8rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 20px;
    color: #fff;
    text-align: center;
}

.highlight {
    color: #ec3750;
}

.sub {
    font-size: 1.1rem;
    color: #8492a6;
    line-height: 1.7;
    max-width: 600px;
    margin: 0 auto 34px;
    text-align: center;
}

.video {
    overflow: hidden;
    border: 1px solid #1e2738;
    margin-bottom: 40px;
}

.video video {
    width: 100%;
    display: block;
}

p {
    font-size: 1rem;
    color: #8492a6;
    line-height: 1.8;
    margin-bottom: 16px;
}

.formula {
    text-align: center;
    font-family: monospace;
    font-size: 1.4rem;
    color: #fff;
    padding: 20px 24px;
    margin: 24px 0 8px;
    background: #110305;
    border: 1px solid #3d1020;
    border-radius: 3px;
}

.note {
    text-align: center;
    font-size: 0.85rem;
    color: #525868;
}

.btns {
    display: flex;
    gap: 12px;
    justify-content: center;
    margin: 32px 0 44px;
}

.btns a {
    text-decoration: none;
}

.btn {
    padding: 12px 24px;
    border-radius: 5px;
    font-weight: 600;
    font-size: 0.9rem;
    background: #ec3750;
    color: #fff;
}

.btn:hover {
    background-color: #d4304a;
}

.hackclub-link {
    padding: 10px 20px;
    border-radius: 3px;
    font-size: 0.85rem;
    color: #7a9cdb;
    border: 1px solid #1e2738;
}

.hackclub-link:hover {
    border-color: #ec3750;
    color: #ec3750;
}

footer {
    text-align: center;
    padding-top: 24px;
    border-top: 1px solid #1e2738;
}

footer p {
    font-size: 0.85rem;
    color: #4d5265;
}
footer a {
    color: #ec3750;
    text-decoration: none;
}

@media (max-width: 600px) {
    .container {
        padding: 40px 15px;
    }
    h1 {
        font-size: 2rem;
    }
}