* {
    padding: 0;
    margin: 0;
}
header, section {
    background-color: #e2e2e2;
    border: 1px dotted red;
    padding: 0px;
    margin: 0px;
}
header {
    height: 100px;
    width: 100%;
    position: fixed;
    top: 0;
}
header ul {
    position: absolute;
    right: 5vw;
    top: 0;
    line-height: 100px;
}
header li {
    display: inline;
    margin: 30px;
    margin-right: 4vw;
}
header a {
    text-decoration: none;
    color: green;
}
header a:hover {
    text-decoration: underline;
}
h1 {
    position: absolute;
    color: red;
    left: 20px;
    top: 0;
    /* padding: 10px; */
    /* margin: 10px; */
    line-height: 100px;
    background-image: url(images/favicon.png);
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
}
body {
    padding-top: 110px;
    font-family: Arial, sans-serif;
    /* padding: 10px; */
    /* margin: 10px; */
    background-color: #f4f4f4;
}
body a {
    text-decoration: none;
    color: purple;
}
body li {
    margin-top: 20px;
    margin-left: 20px;
    /* margin-bottom: 10px; */
}
main a:hover {
    color: orange;
    text-decoration: underline;
}
h2 {
    color: yellow;
}
p {
    font-size: 24px;
    line-height: 1;
}
p::first-line {
    font-weight: bold;
}
ul {
    list-style-type: square;
}
.about {
    background-color: #d0f0c0;
    padding: 20px;
    /* margin-top: 110px; */
    margin-bottom: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
}
.container {
    display: flex;
    flex-direction: row;
}
.container div {
    margin-right: 100px;
}
.container li {
    font-weight: bold;
}
.others {
    background-color: #f0d0c0;
    padding: 20px;
    margin-bottom: 10px;
    display: flex

}
.bye {
    width: 50%;
    text-align: center;
}
.say-bye {
    width: 50%;
    text-align: center;
}
.go {
    background-color: #c0d0f0;
    padding: 10px;
    margin-bottom: 10px;
    /* border: #666 2px dashed; */
}
.go p {
    margin: 10px 0px;
    padding: 10px;
}
.go a {
    font-size: 20px;
    color: #333;
    padding: 10px;
    border: #666 2px dashed;
    border-radius: 5px;
}
.newsletter {
    background-color: #f0c0f0;
    padding: 10px;
    margin-bottom: 10px;
    border: #666 2px solid;
    border-radius: 5px;
}
.newsletter p {
    font-size: 20px;
    margin-bottom: 10px;
}
.newsletter button {
    cursor: pointer;
}
input::placeholder {
    color: #999;
}
footer {
    /* text-align: center; */
    padding: 0px;
    background-color: #e2e2e2;
    border-top: 1px solid #ccc;
    margin-top: 10px;
    display: flex;
    justify-content: left;
    align-items: center;
    /* margin-bottom: 10px; */
}
footer p {
    margin: 0;
    font-size: 14px;
    color: #666;
    display: flex;
    align-items: center;
}
footer img {
    /* vertical-align: middle; */
    margin-right: 10px;
}
.menu {
    display: none;
}

/* 响应式设计语法 */
@media (max-width: 768px) {
    header ul {
        display: none;
    }
    header h1 {
        left: 50%;
        transform: translateX(-50%);
        font-size: 18px;
        white-space: nowrap;
    }
    .menu {
        display: block;
        position: absolute;
        right: 20px;
        top: 35px;
        font-size: 24px;
        background: none;
        border: none;
        cursor: pointer;
    }
    .intro p {
        font-size: 18px;
        width: 100%;
    }
    .container {
        flex-direction: column;
    }
    .container div {
        margin-right: 0;
        width: 100%;
    }
}