/* Reset some default styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  font-family: 'Segoe UI', Arial, sans-serif;
  background: #f4f8fb;
  margin: 0;
  padding: 0;
}

.container {
  background: #fff;
  max-width: 480px;
  margin: 40px auto;
  padding: 32px 24px 24px 24px;
  border-radius: 10px;
  box-shadow: 0 2px 16px rgba(0, 0, 0, 0.08);
  text-align: center;
}

h1 {
  font-weight: 700;
  font-size: 2em;
  margin-bottom: 8px;
  color: #0066b2;
  text-align: center;
}

form {
  text-align: left;
}

.input-group {
  margin-bottom: 18px;
  text-align: center;
}

fieldset.input-group {
  border: 1.5px solid #e0e0e0;
  border-radius: 8px;
  margin-bottom: 18px;
  padding: 12px 16px 8px 16px;
  background: #f9fbfc;
}

/* Wall Details */
fieldset.input-group:nth-of-type(1) {
  background: #e3f2fd; /* Light Blue */
}

/* Brick Details */
fieldset.input-group:nth-of-type(2) {
  background: #fce4ec; /* Light Pink */
}

/* Window Details */
fieldset.input-group:nth-of-type(3) {
  background: #f3e5f5; /* Light Purple */
}

/* Door Details */
fieldset.input-group:nth-of-type(4) {
  background: #e8f5e9; /* Light Green */
}

.input-row {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 8px;
  margin-bottom: 18px;
  text-align: left;
}
.input-row label {
  min-width: unset;
  font-weight: 500;
  color: #333;
  margin-bottom: 0;
  margin-right: 0;
}
.input-row input[type="number"] {
  width: 100%;
  min-width: unset;
  padding: 6px 8px;
  border: 1px solid #cfd8dc;
  border-radius: 5px;
  font-size: 1em;
  background: #f9fbfc;
  transition: border 0.2s;
}
.unit-note {
  color: #888;
  font-size: 0.95em;
  margin-right: 0;
  min-width: unset;
  display: inline-block;
}
@media (max-width: 700px) {
  .input-row {
    flex-direction: column;
    align-items: stretch;
  }
  .input-row label,
  .input-row input[type="number"] {
    width: 100%;
    min-width: unset;
  }
}

p {
  color: #0066b2;
  font-size: 1em;
  text-align: center;
  margin-bottom: 10px;
}

p b {
  font-weight: bold;
}

/* CALCULATE BRICKS button style */
#calculateBtn {
  width: 100%;
  background: linear-gradient(90deg, #42a5f5 0%, #ab47bc 100%);
  color: #fff;
  font-size: 1.15em;
  font-weight: bold;
  border: none;
  border-radius: 6px;
  padding: 14px 0 10px 0;
  margin-top: 12px;
  margin-bottom: 8px;
  box-shadow: 0 2px 8px rgba(66, 165, 245, 0.10);
  cursor: pointer;
  letter-spacing: 0.5px;
  transition: background 0.2s, box-shadow 0.2s, transform 0.1s;
}

#calculateBtn:hover, #calculateBtn:focus {
  background: linear-gradient(90deg, #1976d2 0%, #8e24aa 100%);
  box-shadow: 0 4px 16px rgba(171, 71, 188, 0.13);
  transform: translateY(-2px) scale(1.02);
  outline: none;
}

.result {
  margin: 24px 0 0 0;
  padding: 18px 14px;
  background: #fff3e0;
  border: 2px solid #ffb300;
  border-radius: 10px;
  font-size: 1.35em;
  color: #b26a00;
  font-weight: bold;
  text-align: center;
  box-shadow: 0 2px 12px rgba(255, 179, 0, 0.08);
  letter-spacing: 0.5px;
}

.result strong {
  color: #d84315;
  font-size: 1.25em;
  font-weight: 900;
  letter-spacing: 1px;
  display: block;
  margin-bottom: 6px;
}