body > header {
    position: fixed;
    left: 0;
    top: 0;
    height: 100vh;
    width: var(--导航栏宽度);
    background-color: var(--蓝色);
}

body > header nav {
    display: grid;
    grid-template-rows: repeat(4, 5rem);
    justify-items: center;
    align-items: center;
    text-align: center;
    margin-top: 2.5rem;
    height: 100%;
}

body > header nav a {
    color: var(--白色);
}

body > header svg {
    width: 2rem;
}

.nav-tip {
    position: relative;
    top:-0.6rem;
    font-size: 0.6rem;
    font-weight: bold;
    letter-spacing: 0.1em;
    opacity: 0;
    transition: all 0.3s ease;
}

a:hover .nav-tip {
    opacity: 1;
    top: 0rem;
}

main,
footer {
    margin-left: calc(var(--导航栏宽度) + var(--主体左右单边距));
    margin-right: var(--主体左右单边距);
}

main {
    display: flow-root;
}

main > h1 {
    margin-top: 2rem;
    margin-bottom: 2rem;
    font-family: serif;
    font-size: 3rem;
    border: none;
}

main > a {
    display: grid;
    grid-template-columns: 2rem auto;
    color: var(--灰色);
    margin-bottom: 1rem;
}
main > a:hover {
    background-color: var(--浅蓝色);
    border-radius: 10px;
}

main > a > svg {
    width: 1rem;
    color: var(--蓝色);
    place-self: center;
}

main > a > p {
    grid-column: 2/3;
}

main > a > h2,
main > a > p
{
    font-size: 1rem;
    line-height: 2;
}

#more-button {
    display: block;
    margin: 3rem auto 0 auto;
    padding: 0.75rem;
    width: 70%;
    border: none;
    border-radius: 0.5rem;
    background-color: var(--蓝色);
    color: var(--白色);
    font-size: 1rem;
}