body {
  font-family: 'Roboto', sans-serif;
  background: linear-gradient(135deg, #ece9e6, #ffffff);
  color: #333;
}

html {
  touch-action: manipulation;
}

.container {
  background-color: #fff;
  padding: 30px 40px;
  max-width: 700px;
  margin: 40px auto;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

h1 {
  font-size: 2rem;
  font-weight: 700;
  margin-top: 20px;
  margin-bottom: 20px;
  text-align: center;
}

#desc {
  font-size: 1rem;
  margin-bottom: 20px;
  text-align: center;
  line-height: 1.5;
}

#bpm-wrap {
  background: linear-gradient(135deg, #f6f9fc, #e9eff5);
  border: 1px solid #ddd;
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 20px;
  text-align: center;
}

#bpm {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: 10px;
}

#bpm .label {
  font-size: 1.5rem;
}

.label {
  display: inline-block;
  min-width: 80px;
}

.fraction {
  font-size: 0.6em;
}

button.control {
  height: 100px;
  width: 100%;
  font-size: 1.5rem;
  transition: background-color 0.3s, transform 0.2s;
}

button.control:hover {
  transform: translateY(-3px);
}

#topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
}

#lang_choice {
  text-align: left;
}

#lang_choice button {
  margin-right: 5px;
  border: none;
  background: none;
  cursor: pointer;
  font-weight: 700;
  font-size: 0.9rem;
  color: #555;
  transition: color 0.3s;
}

#lang_choice button:hover,
#lang_choice button.active {
  color: #007bff;
  text-decoration: underline;
}

#page_link {
  text-align: right;
}

#page_link a {
  margin-left: 5px;
  font-weight: 700;
  font-size: 0.9rem;
  color: #555;
  text-decoration: none;
  transition: color 0.3s;
}

#page_link a:hover {
  color: #007bff;
  text-decoration: underline;
}

#logs {
  margin: 20px 0;
  max-height: 300px;
  overflow-y: auto;
  background-color: #f9f9f9;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 4px;
}

#history p {
  margin: 0;
  padding: 0;
  font-size: 0.85rem;
  color: #777;
}

@media (max-width: 576px) {
  #desc {
    font-size: 0.9rem;
    line-height: 1.4;
  }
}