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

body {
    font-family: 'Segoe UI', sans-serif;
    background: #f9fafc;
    color: #333;
    line-height: 1.6;
}

.container {
    width: 90%;
    max-width: 1100px;
    margin: auto;
    padding: 20px 0;
}

.site-header {
    background: #20232a;
    color: #fff;
    padding: 15px 0;
}

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

.logo a {
    color: #61dafb;
    font-size: 1.6rem;
    text-decoration: none;
    font-weight: bold;
}

.main-nav a {
    color: #fff;
    margin-left: 20px;
    text-decoration: none;
    font-weight: 500;
}

.main-nav a:hover {
    color: #61dafb;
}

.site-footer {
    background: #20232a;
    color: #aaa;
    padding: 20px 0;
    text-align: center;
    font-size: 0.9rem;
}

.btn {
    display: inline-block;
    background: #2ecc71;
    color: white;
    padding: 10px 20px;
    border-radius: 8px;
    text-decoration: none;
    margin-top: 15px;
}

.btn:hover {
    background: #27ae60;
}