/* Reset */
body, h1, ul, li, div, label, input, span {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: "Roboto", "Helvetica", "Arial", sans-serif;
  background-color: #f5f5f5;
  color: #212121;
  padding: 20px;
}

/* Title */
h1 {
  font-size: 1.5rem;
  margin-bottom: 20px;
  font-weight: 500;
  text-align: left; /* left-align on desktop */
}

/* Config list container */
#configContainer {
  display: inline-block; /* shrink to content width */
  min-width: 150px;
  margin-bottom: 30px;
}

/* Config list items */
#configList {
  list-style: none;
  margin: 0;
  padding: 0;
}

#configList li {
  background: #fff;
  padding: 12px 16px;
  margin-bottom: 10px;
  border-radius: 8px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.15);
  cursor: pointer;
  transition: transform 0.1s ease, box-shadow 0.2s ease;
  font-size: 1rem;
  text-align: left;
}

#configList li:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

/* Calculator card */
#app {
  background: #fff;
  border-radius: 12px;
  padding: 20px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.15);
  max-width: 400px;
  width: 100%;
  margin-bottom: 30px;
  /* Left align on desktop */
  margin-left: 0;
}

/* Input/output rows */
.field {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.field label {
  font-size: 0.9rem;
  color: #555;
  margin-bottom: 6px;
  flex: 1 0 40%;
}

.field input {
  flex: 1 0 55%;
  padding: 8px 10px;
  border: 1px solid #ccc;
  border-radius: 6px;
  font-size: 0.9rem;
  transition: border-color 0.2s ease;
}

.field input:focus {
  border-color: #3f51b5;
  outline: none;
}

.field span {
  flex: 1 0 55%;
  padding: 8px 10px;
  background: #f0f0f0;
  border-radius: 6px;
  font-size: 0.9rem;
}

/* Responsive adjustments */
@media (max-width: 480px) {
  body {
    padding: 15px;
  }

  h1 {
    font-size: 1.3rem;
  }

  #configContainer {
    display: block;
    width: 100%;
  }

  #configList li {
    font-size: 0.95rem;
    padding: 10px 12px;
  }

  #app {
    padding: 15px;
    margin-left: 0;
  }

  .field {
    flex-direction: column;
    align-items: stretch;
  }

  .field label, .field input, .field span {
    flex: 1 0 100%;
    margin-bottom: 8px;
  }
}