:root {
  --color-bg: #f4f6f9;
  --color-card: #ffffff;
  --color-border: #e0e4ea;
  --color-primary: #2b5fb0;
  --color-primary-dark: #1f4784;
  --color-text: #1e2430;
  --color-text-muted: #5b6472;
  --color-success-bg: #e8f7ee;
  --color-success-text: #1c7a41;
  --color-error-bg: #fdecec;
  --color-error-text: #b3261e;
  --radius: 10px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Segoe UI", "Hiragino Sans", "Yu Gothic", sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
}

.app-header {
  padding: 28px 24px 16px;
  text-align: center;
}

.app-header h1 {
  margin: 0;
  font-size: 28px;
  color: var(--color-primary-dark);
}

.app-header .subtitle {
  font-size: 16px;
  color: var(--color-text-muted);
  font-weight: normal;
}

.tagline {
  margin: 6px 0 0;
  color: var(--color-text-muted);
  font-size: 14px;
}

.tab-nav {
  display: flex;
  justify-content: center;
  gap: 8px;
  padding: 0 16px 20px;
  flex-wrap: wrap;
}

.tab-btn {
  padding: 10px 20px;
  border: 1px solid var(--color-border);
  background: var(--color-card);
  border-radius: 999px;
  cursor: pointer;
  font-size: 14px;
  color: var(--color-text-muted);
  transition: all 0.15s ease;
}

.tab-btn.active {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}

.app-main {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 16px 60px;
}

.tab-panel { display: none; }
.tab-panel.active { display: block; }

.card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 20px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.card h2 {
  margin-top: 0;
  font-size: 18px;
  color: var(--color-primary-dark);
}

.card-desc {
  color: var(--color-text-muted);
  font-size: 13px;
  margin-top: -4px;
}

.mode-toggle {
  display: flex;
  gap: 8px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.mode-btn {
  flex: 1;
  min-width: 200px;
  padding: 10px;
  border: 1px solid var(--color-border);
  background: #f8f9fb;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 13px;
  color: var(--color-text-muted);
}

.mode-btn.active {
  background: #eaf1fc;
  border-color: var(--color-primary);
  color: var(--color-primary-dark);
  font-weight: 600;
}

.field-group {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 14px;
  margin-bottom: 14px;
}

.field-group label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 13px;
  color: var(--color-text-muted);
}

.field-group input[type="number"],
.field-group input[type="text"],
.field-group select {
  padding: 8px 10px;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 14px;
  color: var(--color-text);
}

.checkbox-field {
  flex-direction: row !important;
  align-items: center;
  gap: 8px !important;
}

.checkbox-field input[type="checkbox"] {
  width: 16px;
  height: 16px;
}

.mode-field.hidden { display: none; }

.floor-entry {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 14px;
  margin-bottom: 12px;
  background: #f8f9fb;
}

.remove-entry-btn {
  padding: 6px 12px;
  background: transparent;
  border: 1px solid var(--color-error-text);
  color: var(--color-error-text);
  border-radius: 6px;
  font-size: 12px;
  cursor: pointer;
}

.remove-entry-btn:hover {
  background: var(--color-error-bg);
}

.secondary-btn {
  width: 100%;
  padding: 10px;
  background: #f8f9fb;
  color: var(--color-primary-dark);
  border: 1px dashed var(--color-primary);
  border-radius: var(--radius);
  font-size: 14px;
  cursor: pointer;
  margin-bottom: 14px;
}

.secondary-btn:hover {
  background: #eaf1fc;
}

.calc-btn {
  width: 100%;
  padding: 12px;
  background: var(--color-primary);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  font-size: 15px;
  cursor: pointer;
  margin-top: 6px;
}

.calc-btn:hover { background: var(--color-primary-dark); }

.result-panel { margin-top: 18px; }

.result-summary {
  background: var(--color-success-bg);
  color: var(--color-success-text);
  border-radius: var(--radius);
  padding: 14px 16px;
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 10px;
}

.result-summary.non-compliant {
  background: var(--color-error-bg);
  color: var(--color-error-text);
}

.explanation-list {
  margin: 0;
  padding-left: 18px;
  font-size: 13px;
  color: var(--color-text-muted);
  line-height: 1.7;
}

.explanation-list li { margin-bottom: 4px; }

.error-box {
  background: var(--color-error-bg);
  color: var(--color-error-text);
  border-radius: var(--radius);
  padding: 12px 14px;
  font-size: 14px;
}