html, body, main, header, footer {
  margin: 0px;
  padding: 0px;
}

#app {
  max-width: 720px;
  margin: 0 auto;
  padding: 20px 16px 40px;
}

#app-title {
  text-align: center;
  font-size: 28px;
  font-weight: 700;
  color: #333;
  margin-bottom: 8px;
}

#app-subtitle {
  text-align: center;
  font-size: 14px;
  color: #888;
  margin-bottom: 24px;
}

.card {
  background: #fff;
  border-radius: 12px;
  padding: 20px;
  margin-bottom: 16px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  border: 1px solid #eee;
}

#input-area {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

#date-input-group {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

#date-label {
  font-size: 15px;
  font-weight: 600;
  color: #444;
  white-space: nowrap;
}

#date-picker {
  flex: 1;
  min-width: 160px;
  padding: 10px 14px;
  border: 1px solid #ddd;
  border-radius: 8px;
  font-size: 15px;
  color: #333;
  background: #fafafa;
  cursor: pointer;
  transition: border-color 0.2s, box-shadow 0.2s;
}

#date-picker:focus {
  outline: none;
  border-color: #4A90D9;
  box-shadow: 0 0 0 3px rgba(74, 144, 217, 0.15);
}

#nav-buttons {
  display: flex;
  gap: 12px;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 80px;
  min-height: 44px;
  padding: 10px 20px;
  border: none;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s, background 0.2s;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.btn:active {
  transform: translateY(0);
}

.btn-primary {
  background: #4A90D9;
  color: #fff;
}

.btn-primary:hover {
  background: #3A7BC8;
}

.btn-outline {
  background: #fff;
  color: #4A90D9;
  border: 1px solid #4A90D9;
}

.btn-outline:hover {
  background: #f0f7ff;
}

#result-area {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.result-item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  padding: 14px 16px;
  border-bottom: 1px solid #f0f0f0;
  gap: 8px;
}

.result-item:last-child {
  border-bottom: none;
}

.result-label {
  font-size: 14px;
  font-weight: 600;
  color: #666;
  min-width: 110px;
  flex-shrink: 0;
}

.result-value {
  font-size: 18px;
  font-weight: 700;
  color: #4A90D9;
  flex: 1;
}

.result-desc {
  font-size: 12px;
  color: #aaa;
  width: 100%;
  margin-top: 2px;
}

#features h2,
#scenarios h2,
#FAQ h2 {
  font-size: 20px;
  font-weight: 600;
  color: #333;
  margin-bottom: 12px;
}

#features p {
  font-size: 14px;
  color: #666;
  line-height: 1.8;
}

#scenarios ul {
  padding-left: 20px;
  margin: 0;
}

#scenarios li {
  font-size: 14px;
  color: #666;
  line-height: 1.8;
  margin-bottom: 4px;
}

#FAQ dl {
  margin: 0;
}

#FAQ dt {
  font-size: 15px;
  font-weight: 600;
  color: #444;
  margin-top: 16px;
  margin-bottom: 6px;
}

#FAQ dd {
  font-size: 14px;
  color: #666;
  line-height: 1.7;
  margin-left: 0;
  margin-bottom: 4px;
}

#__fork {
  text-align: center;
  padding: 24px 0;
}

#__fork button {
  min-width: 160px;
  min-height: 44px;
  padding: 10px 28px;
  background: #4A90D9;
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 15px;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
}

#__fork button:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

@media (max-width: 767px) {
  #app {
    padding: 12px 12px 32px;
  }

  #app-title {
    font-size: 22px;
  }

  #date-input-group {
    flex-direction: column;
    align-items: stretch;
  }

  #date-label {
    margin-bottom: 4px;
  }

  #date-picker {
    width: 100%;
    box-sizing: border-box;
  }

  #btn-today {
    width: 100%;
  }

  .result-item {
    flex-direction: column;
    padding: 12px 12px;
  }

  .result-label {
    min-width: auto;
    margin-bottom: 2px;
  }

  .result-value {
    font-size: 16px;
  }
}