:root {
  --bg: radial-gradient(1200px 600px at 10% 10%, #e6f7ff 0%, #ffffff 40%, #fefefe 100%);
  --calc-ar: 5 / 7;
}

html, body {
  height: 100%;
}

body {
  background: var(--bg);
}

html body {
  padding-top: 0;
}

.calc-wrap {
  aspect-ratio: var(--calc-ar);
  width: min(100vw, calc(100vh * var(--calc-ar)));
  height: auto;
}

.card, .card-body {
  height: 100%;
}

.card-body {
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}

.form-container {
  flex: 1;
}

.conversion-container {
  display: flex;
  flex-direction: column;
  gap: 15px;
  padding: 20px;
  background: linear-gradient(135deg, #667eea22 0%, #764ba222 100%);
  border-radius: 0.5rem;
  margin-bottom: 15px;
}

.conversion-box {
  flex: 1;
}

.conversion-box input {
  font-size: 1.1rem;
  font-weight: 600;
}

.swap-container {
  display: flex;
  justify-content: center;
  align-items: center;
}

#swap-btn {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.3s ease;
}

#swap-btn:hover {
  transform: rotate(180deg);
}

.formula-box {
  padding: 15px;
  background: #f8f9fa;
  border-radius: 0.375rem;
  border-left: 4px solid #0d6efd;
}

#formula-display {
  font-family: 'Courier New', monospace;
  font-size: 0.95rem;
  word-break: break-word;
}

.quick-conversions {
  padding: 15px;
  background: #f8f9fa;
  border-radius: 0.375rem;
}

.quick-conversions .table {
  margin-bottom: 0;
  font-size: 0.9rem;
}

@media (max-width: 575.98px) {
  .calc-wrap {
    width: 100vw;
    height: 100vh;
    aspect-ratio: auto;
  }

  .conversion-container {
    padding: 15px;
  }

  .conversion-box input {
    font-size: 1rem;
  }

  #formula-display {
    font-size: 0.85rem;
  }
}

@media (min-width: 576px) and (max-width: 991.98px) {
  :root { 
    --calc-ar: 6 / 8; 
  }
}

@media (min-width: 992px) {
  :root { 
    --calc-ar: 5 / 7; 
  }
}