:root {
    --md3-primary: #2962FF; /* Blue 800 */
    --md3-primary-container: #82B1FF; /* Light Blue */
}

/* Mobile Dark Mode — Material 3 Expressive Style */
body {
    font-family: "Roboto", "Segoe UI", sans-serif;
    background-color: #121212;
    color: #E3E3E3;
    margin: 0;
    padding: 0;
    text-align: center;
}

.container {
    padding: 20px;
    background-color: #1E1E1E;
    border-radius: 24px;
    margin: 12px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.4);
    border: 1px solid rgba(255, 255, 255, 0.05);
}

h1 {
    font-size: 2em;
    margin-bottom: 28px;
    font-weight: 500;
    color: #FFFFFF;
}

.button-group {
    display: flex;
    flex-direction: column;
    gap: 18px;
}

button {
    background-color: var(--md3-primary);
    color: white;
    border: none;
    padding: 18px;
    font-size: 1.3em;
    border-radius: 30px;
    cursor: pointer;
    font-weight: 500;
    box-shadow: 0 2px 6px rgba(0,0,0,0.3);
    transition: background-color 0.25s ease, box-shadow 0.25s ease, transform 0.15s ease;
}

button:active {
    transform: scale(0.97);
    background-color: var(--md3-primary-container);
}

.status-container {
    margin-top: 28px;
    font-size: 1.2em;
}

.status-text {
    display: block;
    margin-top: 10px;
}

.status-text.green {
    color: #4CAF50;
    font-weight: 600;
}

.status-text.red {
    color: #FF6D60;
    font-weight: 600;
}

/* Material 3 Spinner */
.spinner {
  display: none;
  width: 64px;
  height: 64px;
  margin: 24px auto 0;
  animation: spinner-rotate 2s linear infinite;
  transform-origin: 50% 50%;
}

.spinner.visible {
  display: block;
}

.spinner .path {
  stroke: var(--md3-primary);
  stroke-linecap: round;
  stroke-dasharray: 90, 150;
  stroke-dashoffset: 0;
  animation: spinner-dash 1.5s ease-in-out infinite;
}

/* Rotation animation on the whole SVG */
@keyframes spinner-rotate {
  100% {
    transform: rotate(360deg);
  }
}

/* Stroke dash animation on the circle */
@keyframes spinner-dash {
  0% {
    stroke-dasharray: 1, 150;
    stroke-dashoffset: 0;
  }
  50% {
    stroke-dasharray: 90, 150;
    stroke-dashoffset: -35;
  }
  100% {
    stroke-dasharray: 90, 150;
    stroke-dashoffset: -124;
  }
}