.main-block > section {
    width: 92%;
    max-width: 960px;
    margin: 0 auto;
    padding: 80px 0 0;
}

button.mute {
    background: #eee;
    color: lightblue;
}

.clearfix::after {
  content: "";
  clear: both;
  display: table;
}

.aa-box {
    align-items: baseline;
}

.aa-button {
    margin: 0;
    margin-right: auto;
}

body {
    background: #fbfffe;
}

.head-img {
    width: 60px;
    height: auto;
}

.head-logo {
    text-decoration: none;
    color: #001f3f;
    font-weight: bold;
    font-size: 22px;
    margin-right: auto;
    margin-left: 20px;
}

nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px;
    background-color: #f0f0f0;
}

.menu {
    gap: 10px;
    display: flex;
}

.menu a {
    text-decoration: none;
    color: #333;
    padding: 5px 10px;
    border-radius: 5px;
    background-color: #ddd;
}

.np-box {
    display: flex;
    justify-content: center;
    align-items: center;
}

.foot {
    margin-left: auto;
    margin-right: auto;
    text-align: center;
}

.small-up {
    height: 50px;
    border: 1px solid #aaaaaa;
}

.centerd-block {
    margin: 0 auto;
}

.small-block{
    max-width: 600px;
}

.center {
    text-align: center;
}

a.active-nav {
    background: #ddd !important;
}

.demo-note {
    margin-left: auto;
    margin-right: auto;
    margin-bottom: 20px;
    text-align: center;
    color: #aaaaaa;
}

.chat-box {
    display: grid;
}

.chat-preview {
    margin-top: 20px;
    color: #444444;
}