body {
    margin: 0;
}

h1 {

}

.menu {
    border-bottom: 1px solid lightgrey;
    background-color: aliceblue;
}

.menu li {
    display: inline-block;
    padding: 0 10px;
}
.menu li.sel {
    border-bottom: 3px solid blue;
}
input[type=edit] {
    font-size: 1.2rem;
    border: solid 1px lightgray;
    border-radius: 5px;
}
input[type=button], input[type=submit] {
    font-size: 1.2rem;
    margin: 1rem 0.2rem;
    font-size: 20px;
}
.block {
    border: 1px solid lightgray;
    border-radius: 10px;
    padding: 10px;
    width: 550px;
    margin-top: 10px;
}
div.exercises {
    clear: both;
    overflow: auto;
    padding: 5px 0;
    margin-left: -5px;
}
div.exercise, .exercise-placeholder {
    border-radius: 10px;
    padding: 10px;
    width: 240px;
    height: 60px;
    float: left; 
    margin: 5px;
    background-color: white;
}
div.exercise {
    border: 2px solid lightgray;
}
.exercise-placeholder {
    border: 2px solid lightgray;
    border-style: dashed;
    /* background-color: lightgrey; */
}