html {
  font-size: 14px;
}

.center-viewport {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

@media (min-width: 768px) {
  html {
    font-size: 16px;
  }
}

.btn:focus, .btn:active:focus, .btn-link.nav-link:focus, .form-control:focus, .form-check-input:focus {
  box-shadow: 0 0 0 0.1rem white, 0 0 0 0.25rem #258cfb;
}

html {
  position: relative;
  min-height: 100%;
}

body {
    background-color: #000000;
    margin-bottom: 60px;
}

.fixed-m-btn {
    position: fixed;
    bottom: 32px;
    right: 32px;
    z-index: 1000;
}
.dark-square-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    background-color: #101010; /* darker grey */
    color: #222; /* dark text */
    font-size: 1rem;
    font-weight: bold;
    text-decoration: none;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
    border: none;
    transition: background 0.2s, color 0.2s;
}

.dark-square-btn:hover {
    background-color: #181818;
    color: #111;
}