body {
    font-family: Arial, sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 0;
    padding: 20px;
    background-color: #000000;
    color: #E8E6E3;
}

#staff {
    position: relative;
    width: 90%;
    max-width: 600px;
    height: auto;
    border: 0 solid #E8E6E3;
    border-radius: 0;
    box-shadow: 0 0 0 rgba(0, 0, 0, 0.1);
    margin: 30px 0;
}

.staff-line {
    width: 100%;
    height: 2px;
    background: #E8E6E3;
    position: absolute;
}

.extra-line {
    display: none;
    width: 50px;
    height: 2px;
    background: #E8E6E3;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    margin-left: 10px;
    transition-delay: 1s;
}

.extra-line:nth-child(1) { top: -40px; }
.extra-line:nth-child(2) { top:  -20px; }

.treble-line:nth-child(3) { top: 0px; }
.treble-line:nth-child(4) { top: 20px; }
.treble-line:nth-child(5) { top: 40px; }
.treble-line:nth-child(6) { top: 60px; }
.treble-line:nth-child(7) { top: 80px; }

.extra-line:nth-child(8) { top: 100px; }
.extra-line:nth-child(9) { top: 120px; }

.extra-line:nth-child(10) { top: 120px; }
.extra-line:nth-child(11) { top: 140px; }

.bass-line:nth-child(12) { top: 160px; }
.bass-line:nth-child(13) { top: 180px; }
.bass-line:nth-child(14) { top: 200px; }
.bass-line:nth-child(15) { top: 220px; }
.bass-line:nth-child(16) { top: 240px; }

.extra-line:nth-child(17) { top: 260px; }
.extra-line:nth-child(18) { top: 280px; }

#line {
    position: absolute;
    height: 2px;
    background-color: black;
    width: 100%;
}

#noteDisplay {
    position: absolute;
    font-size: 8vw;
    top: 10vw; 
    left: 50%;
    transform: translateX(-50%);
    
}

.note-display {
    position: absolute;
    left: 50%;
    top: 30%;
    transform: translate(-50%, -50%);
    font-size: 6vw;
    font-weight: bold;
    color: #E8E6E3;
    transition: top 0.5s;
}

#buttons {
    display: flex;
    flex-direction: column;
    gap: 10px;
    align-items: center;
    margin-top: 10px;
    padding: 0 10vw; 
}

button {
   
    width: 11vw;
    height: 11vw;
    font-size: 5vw; 
    text-align: center;
    padding: 0;
  /*  background-color: #e0e0e0;*/
    border: none;
    border-radius: 8px;
    cursor: pointer;
 /*   box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2); */
    transition: background-color 0.3s ease, transform 0.1s ease;
}

.button-row {
    display: flex;
    gap: 10px;
    justify-content: center;
    padding: 0 0vw;
}

button:active {
    transform: scale(0.95);
}


.spacer {
    height: 300px;
}

.spacer2 {
    height: 20px;
}

.note-name {
    display: none;
}

@media (min-width: 600px) {
    #noteDisplay {
        font-size: 40px;
        top: 70px;
    }

    .note-display {
        font-size: 24px;
    }

    button {
        width: 60px;
        height: 60px;
        font-size: 18px;
    }
    .keyboard {
        height: 30vw; 
    }

    .white-key {
        font-size: 5vw; 
    }

    .black-key {
        font-size: 5vw;
    }
}


.sidebar {
    height: 100%;
    width: 0;
    position: fixed;
    top: 0;
    right: -10px;
    background-color: #333333be;
    color: #e0e0e0;
    overflow-x: hidden;
    transition: 0.3s;
    padding-top: 60px;
    padding-left: 10px;
    z-index: 2;
    border-top-left-radius: 10px;
    border-bottom-left-radius: 10px;
    
}

.sidebar .close-button {
    position: absolute;
    top: 10px;
    right: 30px;
    font-size: 36px;
    cursor: pointer;
    z-index: 2;
}

.version-name {
    position: absolute;
    bottom: 100px; 
    left: 50%; 
    transform: translateX(-50%); 
    font-size: 1.5em; 
    color: #e0e0e0; 
    z-index: 3;
}

.kontakt {
    position: absolute;
    bottom: 80px; 
    left: 50%; 
    transform: translateX(-50%); 
    font-size: 0,5em; 
    color: #e0e0e0; 
    z-index: 3;
}

#settingsButton {
    position: fixed;
    top: 10px;
    right: 10px;
    z-index: 3;
    font-size: 18px;
    padding: 10px;
    cursor: pointer;
    z-index: 2;
}

.overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.267);
    z-index: 1;
    color: #e0e0e0;
}

.custom-checkbox {
    z-index: 5;
}

.keyboard {
    display: flex;
    position: relative;
    height: 25vw; 
    width: 100%; 
    margin: 20px auto; 
    z-index: 0;
}

.white-key {
    flex: 1;
    height: 100%;
    background-color: #e0e0e0;
    border: 1px solid black;
    position: relative;
    text-align: center;
    font-weight: bold;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    font-size: 6vw; 
    color: black;

}

.black-key {
    position: absolute;
    height: 60%; 
    width: calc(100% / 10); 
    background-color: black;
    color: #e0e0e0;
    font-size: 3.5vw; 
    text-align: center;
    border: 1px solid black;
    z-index: 1;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    font-weight: bold;
}


.black-key:nth-child(2) {
    left: calc(100% / 7 * 1 - (100% / 10) / 2);
    content: " D♭";
}
.black-key:nth-child(4) {
    left: calc(100% / 7 * 2 - (100% / 10) / 2);
}
.black-key:nth-child(7) {
    left: calc(100% / 7 * 4 - (100% / 10) / 2);
}
.black-key:nth-child(9) {
    left: calc(100% / 7 * 5 - (100% / 10) / 2);
}
.black-key:nth-child(11) {
    left: calc(100% / 7 * 6 - (100% / 10) / 2);
}

.black-key.correct {
    background-color: rgb(7, 168, 7);
    color: #E8E6E3;
}

.black-key.wrong {
    background-color: red;
    color: #E8E6E3;
}

.white-key.correct {
    background-color: rgb(7, 168, 7);
    color: #E8E6E3;
}

.white-key.wrong {
    background-color: red;
    color: #E8E6E3;
}

.custom-checkbox input[type="checkbox"] {
    display: none;
}

.custom-checkbox label {
    display: inline-block;
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
    border-radius: 5px;
    background-color: #ff0000;
    color: white;
    transition: background-color 0.3s;
    margin-top: 10px
}

.custom-checkbox label:hover {
    background-color: #ff0000;
}

.custom-checkbox input[type="checkbox"]:checked + label {
    background-color: #28a745;
}