/* unit — 與全站色票一致；.unit-input 寬度上限 50%，小螢幕 90% */

body.page-unit {
  margin: 0;
  font-family: "Noto Sans TC", "Microsoft JhengHei", Arial, sans-serif;
  --u-platinum: #eeeeee;
  --u-inferno: #a80000;
  --u-inferno-soft: rgba(168, 0, 0, 0.12);
  --u-inferno-border: rgba(168, 0, 0, 0.35);
  --u-gunmetal: #424242;
  --u-granite: #958e8a;
  --u-gray-light: #f5f5f5;
  --u-gray-mid: #d0d0d0;
  --u-gray-dark: #2c2c2c;
  --u-surface: #ffffff;
  background: linear-gradient(180deg, var(--u-gray-light) 0%, var(--u-platinum) 50%, #e8e8e8 100%);
  min-height: 100vh;
  color: var(--u-gunmetal);
}

body.page-unit * {
  box-sizing: border-box;
}

body.page-unit .container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 1.5rem 1rem;
}

body.page-unit .title-section {
  text-align: center;
  margin-bottom: 2rem;
}

body.page-unit .main-title {
  font-size: 2rem;
  font-weight: 700;
  color: var(--u-gunmetal);
  margin-bottom: 0.5rem;
  text-shadow: none;
}

body.page-unit .subtitle {
  color: var(--u-granite);
  font-size: 1rem;
}

body.page-unit .category-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
  margin-bottom: 2rem;
}

body.page-unit .category-tab {
  padding: 0.75rem 1.5rem;
  background: var(--u-inferno-soft);
  color: var(--u-gunmetal);
  border: 1px solid var(--u-inferno-border);
  border-radius: 0.75rem;
  cursor: pointer;
  transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
  font-size: 0.95rem;
  font-weight: 600;
}

body.page-unit .category-tab:hover {
  background: rgba(168, 0, 0, 0.18);
}

body.page-unit .category-tab.active {
  background: var(--u-inferno);
  color: #fff;
  border-color: var(--u-inferno);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(168, 0, 0, 0.3);
}

body.page-unit .converter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}

body.page-unit .converter-card {
  background: var(--u-surface);
  border-radius: 1rem;
  padding: 1.5rem;
  border: 1px solid var(--u-gray-mid);
  box-shadow: 0 8px 24px rgba(66, 66, 66, 0.08);
  display: none;
}

body.page-unit .converter-card.active {
  display: block;
  animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

body.page-unit .converter-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--u-inferno);
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 2px solid var(--u-gray-mid);
  background: none;
  -webkit-background-clip: unset;
  -webkit-text-fill-color: unset;
  background-clip: unset;
}

/* 中欄最多佔列寬 50%，左右 1fr 對稱，輸入框在整列視覺水平置中 */
body.page-unit .unit-row {
  display: grid;
  grid-template-columns: 1fr minmax(0, 50%) 1fr;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

body.page-unit .unit-label {
  grid-column: 1;
  justify-self: end;
  min-width: 0;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--u-gunmetal);
  text-align: right;
}

body.page-unit .unit-input {
  grid-column: 2;
  width: 100%;
  max-width: 100%;
  padding: 0.625rem 0.875rem;
  font-size: 1rem;
  border: 2px solid var(--u-gray-mid);
  border-radius: 0.5rem;
  transition: border-color 0.2s, box-shadow 0.2s;
  font-weight: 700;
  text-align: center;
  color: var(--u-gray-dark);
  background: var(--u-surface);
}

body.page-unit .unit-input:focus {
  outline: none;
  border-color: var(--u-inferno);
  box-shadow: 0 0 0 3px rgba(168, 0, 0, 0.12);
}

body.page-unit .unit-input:hover {
  border-color: var(--u-granite);
}

body.page-unit .info-box {
  background: var(--u-surface);
  border-radius: 1rem;
  border: 1px solid var(--u-gray-mid);
  box-shadow: 0 8px 24px rgba(66, 66, 66, 0.08);
  padding: 2rem 1.5rem;
  margin-top: 2rem;
}

body.page-unit .info-box h3 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--u-inferno);
  margin-bottom: 1.5rem;
  text-align: center;
  background: none;
  -webkit-background-clip: unset;
  -webkit-text-fill-color: unset;
  background-clip: unset;
}

body.page-unit .info-content {
  color: var(--u-gunmetal);
  line-height: 1.8;
}

body.page-unit .info-content h4 {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--u-gunmetal);
  margin: 1.5rem 0 0.75rem 0;
}

body.page-unit .info-content p {
  margin-bottom: 1rem;
}

body.page-unit .info-content ul {
  margin-left: 1.5rem;
  margin-bottom: 1rem;
}

body.page-unit .info-content li {
  margin: 0.5rem 0;
}

body.page-unit .info-content strong {
  color: var(--u-inferno);
  font-weight: 600;
}

body.page-unit .formula-box {
  background: var(--u-gray-light);
  border-left: 4px solid var(--u-inferno);
  padding: 1rem 1.5rem;
  margin: 1rem 0;
  border-radius: 0.5rem;
  border: 1px solid var(--u-gray-mid);
  font-family: "Courier New", monospace;
}

body.page-unit .tip-box {
  background: var(--u-platinum);
  border-left: 4px solid var(--u-granite);
  padding: 1rem 1.5rem;
  margin: 1rem 0;
  border-radius: 0.5rem;
  border: 1px solid var(--u-gray-mid);
}

body.page-unit .hero {
  text-align: center;
  color: var(--u-gunmetal);
  margin-bottom: 3rem;
}

body.page-unit .hero h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.12);
}

body.page-unit .hero p {
  font-size: 1.2rem;
  opacity: 1;
}

body.page-unit .calculator-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

body.page-unit .calculator-card {
  background: var(--u-platinum);
  border: 1px solid var(--u-gray-mid);
  border-radius: 15px;
  padding: 1rem;
  box-shadow: 0 8px 20px rgba(66, 66, 66, 0.1);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  cursor: pointer;
}

body.page-unit .calculator-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 28px rgba(66, 66, 66, 0.14);
}

body.page-unit .calculator-card a {
  text-decoration: none;
  font-weight: 700;
  color: var(--u-gunmetal);
}

body.page-unit .calculator-card h3 {
  color: var(--u-gunmetal);
  margin-bottom: 1rem;
  font-size: 1rem;
}

body.page-unit .calculator-card p {
  color: var(--u-granite);
  line-height: 1;
}

body.page-unit .icon {
  font-size: 2rem;
  margin-bottom: 0;
}

@media (max-width: 640px) {
  body.page-unit .main-title {
    font-size: 1.5rem;
  }

  body.page-unit .category-tab {
    font-size: 0.875rem;
    padding: 0.625rem 1rem;
  }

  body.page-unit .unit-row {
    grid-template-columns: 1fr;
    justify-items: stretch;
  }

  body.page-unit .unit-label {
    grid-column: 1;
    justify-self: start;
    text-align: left;
  }

  body.page-unit .unit-input {
    grid-column: 1;
    max-width: 90%;
    width: 100%;
    margin-left: auto;
    margin-right: auto;
  }

  body.page-unit .converter-grid {
    grid-template-columns: 1fr;
  }
}

@media (min-width: 768px) {
  body.page-unit .desktop-nav {
    display: flex;
  }

  body.page-unit .menu-btn {
    display: none;
  }

  body.page-unit .container {
    padding: 2.5rem 1.5rem;
  }
}

@media (min-width: 1024px) {
  body.page-unit .nav-link {
    font-size: 1rem;
  }
}