style.css

* {
    margin: 0;
    padding: 0;
    border: none;
    outline: none;
}

main {
    display: flex;
    align-items: center;
    flex-direction: column;
    margin: auto;
    width: 1000px;
}

h1 {
    margin-top: 16px;
    font-size: 48px;
}

.input_nova_tarefa {
    margin-top: 32px;
    width: 70%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.input_nova_tarefa input {
    border-bottom: 1px solid #1e1c1c;
    margin-right: 16px;
    font-size: 24px;
    width: 100%;
}

.input_nova_tarefa button {
    padding: 4px 16px;
    border-radius: 34px;
    cursor: pointer;
    background-color: #2bff7c;
    color: #ffff;
    font-size: 24px;
}

.lista {
    margin-top: 32px;
    width: 70%;
}

ul {
    margin-top: 16px;
}

li {
    list-style-type: none;
    text-align: left;
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid #1e1c1c;
    margin-bottom: 24px;
    font-size: 24px;
}

a {
    text-decoration: none;
    color: tomato;
    cursor: pointer;
}