body {
    margin: 0;
    font-family: Helvetica, Arial, sans-serif;
    background: #f0f2f5;
}

.header {
    background: rgba(17, 25, 40, 0.95);
    color: white;
    padding: 15px 30px;
    font-size: 22px;
    font-weight: bold;
}

.container {
    max-width: 900px;
    margin: 40px auto;
    background: #ffffff;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}

h1 {
    margin-bottom: 30px;
}

.section {
    border-bottom: 1px solid #eee;
    padding: 15px 0;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: 600;
    color: #1c1e21;
    transition: 0.2s;
}

.section:hover {
    color: #1877f2;
}

.arrow {
    transition: 0.3s;
}

.content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease;
}

.content-inner {
    background: #f7f8fa;
    padding: 20px;
    border-radius: 12px;
    margin: 15px 0;
    font-weight: normal;
    color: #444;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.active .arrow {
    transform: rotate(90deg);
}

a {
    color: #1877f2;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}