@import url('https://fonts.googleapis.com/css?family=Muli&display=swap');

:root {
  --progress-fill-color: #2ecc71; /* Green */
  --progress-empty-color: #bdc3c7; /* Light grey */
  --text-color: #34495e; /* Dark blue-grey */
}

* {
  box-sizing: border-box;
}

body {
  background-color: #f4f7f6; /* Light grey background */
  font-family: 'Muli', sans-serif;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
  overflow: hidden;
  margin: 0;
}

.main-container {
  text-align: center;
  background-color: #ffffff; /* White background for container */
  padding: 40px;
  border-radius: 10px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1); /* Subtle shadow */
}

h1 {
  margin-bottom: 30px;
  color: var(--text-color);
}

.progress-indicator-container {
  display: flex;
  justify-content: space-between;
  position: relative;
  margin-bottom: 40px; /* Increased margin */
  max-width: 100%;
  width: 450px; /* Wider progress bar */
}

.progress-indicator-container::before {
  content: '';
  background-color: var(--progress-empty-color);
  position: absolute;
  top: 50%;
  left: 0;
  transform: translateY(-50%);
  height: 4px;
  width: 100%;
  z-index: -1;
}

.progress-line {
  background-color: var(--progress-fill-color);
  position: absolute;
  top: 50%;
  left: 0;
  transform: translateY(-50%);
  height: 4px;
  width: 0%;
  z-index: -1;
  transition: 0.4s ease;
}

.step-circle {
  background-color: #ffffff; /* White circle background */
  color: var(--progress-empty-color);
  border-radius: 50%;
  height: 35px; /* Slightly larger circles */
  width: 35px; /* Slightly larger circles */
  display: flex;
  align-items: center;
  justify-content: center;
  border: 3px solid var(--progress-empty-color);
  transition: 0.4s ease;
  font-weight: bold;
}

.step-circle.active {
  border-color: var(--progress-fill-color);
  color: var(--progress-fill-color); /* Green text for active circle */
}

.nav-btn {
  background-color: #3498db; /* Blue button */
  color: #fff;
  border: 0;
  border-radius: 6px;
  cursor: pointer;
  font-family: inherit;
  padding: 10px 30px; /* Increased padding */
  margin: 5px;
  font-size: 16px; /* Larger font */
  transition: background-color 0.3s ease;
}

.nav-btn:active {
  transform: scale(0.98);
}

.nav-btn:focus {
  outline: 0;
}

.nav-btn:hover:not(:disabled) {
  background-color: #2980b9; /* Darker blue on hover */
}

.nav-btn:disabled {
  background-color: var(--progress-empty-color);
  cursor: not-allowed;
}

.reset-btn {
  background-color: #e74c3c; /* Red reset button */
}

.reset-btn:hover:not(:disabled) {
  background-color: #c0392b; /* Darker red on hover */
}