html {
  height: 100%;
}
header {
  background: #3c444a;
  color: antiquewhite;
  font-size: 30px;
  font-weight: 400;
  text-align: center;
  padding: 10px 5px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  border-radius: 5px 5px 0 0;
}
.notes {
  position: relative;
  margin: 20px auto 0 auto;
  width: 80%;
  text-align: center;
}

.note {
  font-size: 30px;
  font-weight: bold;
  position: relative;
  display: inline-block;
  padding-right: 30px;
  padding-left: 10px;
}

.note.active {
  color: #3c9ae7;
}

.notes-list {
  overflow: auto;
  overflow: -moz-scrollbars-none;
  white-space: nowrap;
  -ms-overflow-style: none;
  -webkit-mask-image: -webkit-linear-gradient(
    left,
    rgba(255, 255, 255, 0),
    #fff,
    rgba(255, 255, 255, 0)
  );
}

.notes-list::-webkit-scrollbar {
  display: none;
}

.note {
  -webkit-tap-highlight-color: transparent;
}

.note span {
  position: absolute;
  right: 0.25em;
  font-size: 40%;
  font-weight: normal;
}

.note-sharp {
  top: 0.3em;
}

.note-octave {
  bottom: 0.3em;
}

.frequency {
  font-size: 32px;
}

.frequency span {
  font-size: 50%;
  margin-left: 0.25em;
}
.meter_section {
  position: relative;
  width: 100%;
  height: 100px;
  margin: 20px 0;
}
.meter {
  position: absolute;
  right: 50%;
  top: 20px;
  height: 90%;
}

.meter-pointer {
  width: 2px;
  height: 100%;
  background: #3c9ae7;
  transform: rotate(45deg);
  transform-origin: bottom;
  transition: transform 0.5s;
  position: absolute;
  right: 50%;
}

.meter-dot {
  width: 10px;
  height: 10px;
  background: #3c9ae7;
  border-radius: 50%;
  position: absolute;
  bottom: -5px;
  right: 50%;
  margin-right: -4px;
}

.meter-scale {
  width: 1px;
  height: 100%;
  transform-origin: bottom;
  transition: transform 0.2s;
  box-sizing: border-box;
  border-top: 10px solid;
  position: absolute;
  right: 50%;
}

.meter-scale-strong {
  width: 2px;
  border-top-width: 20px;
}

.frequency-bars {
  position: absolute;
  height: 25%;
  opacity: .05;
  width: 100%;
  bottom: 0;
}

.swal-button {
  background: #3c9ae7;
}

.a4 {
  text-align: center;
  margin: 10px auto;
}

.a4 span {
  color: #3c9ae7;
  cursor: pointer;
}

.auto {
  text-align: center;
  margin: 10px auto;
}

.tuner-section {
  position: relative;
  display: flex;
  justify-content: center;
  color: antiquewhite;
  flex-direction: column;
  margin: 30px 15px;
}
.tuner-section>div {
  z-index: 1;
}
.modal {
  display: none;
  position: fixed;
  z-index: 2;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  overflow: auto;
  background-color: rgba(0,0,0,0.4);
}

.modal-content {
  background-color: #fefefe;
  margin: 15% auto;
  padding: 20px;
  border: 1px solid #888;
  width: 70%;
}

input[type=number] {
  width: 100%;
  padding: 12px 20px;
  margin: 8px 0;
  box-sizing: border-box;
}
@media (min-width: 350px) {
  .meter_section {
    height: 150px;
  }
  .note {
    font-size: 45px;
  }
}
@media (min-width: 768px) {
  .note {
    font-size: 90px;
  }
  .modal-content {
    width: 30%;
  }
  .meter_section {
    height: 200px;
  }
}