/* ============================================
   Steel Weight Calculator — Tool-specific styles
   Uses only CSS variables from /assets/css/style.css
   ============================================ */

/* ── Tabs ── */
.calc-tabs {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 24px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}
.calc-tabs::-webkit-scrollbar { display: none; }
.calc-tab {
  padding: 12px 16px;
  cursor: pointer;
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--color-muted);
  border: none;
  background: none;
  border-bottom: 2px solid transparent;
  white-space: nowrap;
  transition: color 0.2s ease, border-color 0.2s ease;
  min-height: 44px;
}
.calc-tab:hover { color: var(--color-text); }
.calc-tab.active {
  color: var(--color-text);
  border-bottom-color: var(--color-primary);
}

/* ── Tab Panels ── */
.tab-panel { display: none; }
.tab-panel.active { display: block; padding-top: 20px; }

/* ── Unit Toggle ── */
.unit-toggle {
  display: flex;
  gap: 8px;
  margin-bottom: 24px;
}
.unit-pill {
  padding: 8px 18px;
  border-radius: 20px;
  border: 1px solid var(--color-border);
  background: var(--color-surface2);
  color: var(--color-muted);
  cursor: pointer;
  font-size: 12px;
  font-family: var(--font-mono);
  letter-spacing: 1px;
  text-transform: uppercase;
  min-height: 36px;
  transition: all 0.2s ease;
}
.unit-pill.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: white;
}

/* ── Sub-mode Toggle ── */
.sub-mode-toggle {
  display: flex;
  gap: 6px;
  margin-bottom: 20px;
}

/* ── Standard Size Row ── */
.standard-size-row {
  display: flex;
  gap: 12px;
  align-items: center;
  margin-bottom: 16px;
}
.standard-size-row .form-group { flex: 1; margin-bottom: 0; }
.kgpm-display {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--color-yellow);
  background: var(--color-surface2);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 10px 14px;
  min-width: 100px;
  text-align: center;
  white-space: nowrap;
  flex-shrink: 0;
}

/* ── Wastage ── */
.wastage-group {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}
.wastage-btn {
  padding: 8px 16px;
  border-radius: 6px;
  border: 1px solid var(--color-border);
  background: var(--color-surface2);
  color: var(--color-muted);
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 1px;
  min-height: 36px;
  transition: all 0.2s ease;
}
.wastage-btn.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: white;
}

/* ── Results Grid ── */
.result-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  margin-top: 20px;
}
.result-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 10px;
  padding: 18px 20px;
}
.result-card.primary { grid-column: 1 / -1; }
.result-card.highlight { border-left: 3px solid var(--color-primary); }
.result-num {
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 600;
  color: var(--color-yellow);
  line-height: 1;
}
.result-lbl {
  font-family: var(--font-mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--color-muted);
  margin-bottom: 6px;
}
.result-sub {
  font-size: 12px;
  color: var(--color-muted);
  margin-top: 4px;
}
.result-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}
.result-actions h3 {
  font-family: var(--font-heading);
  font-size: 22px;
  letter-spacing: 1px;
  margin: 0;
}
.result-actions-btns {
  display: flex;
  gap: 8px;
}
.results-note {
  font-size: 12px;
  color: var(--color-muted);
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--color-border);
  line-height: 1.7;
}

/* ── Trust Chips ── */
.trust-chips {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-top: 20px;
}

/* ── FAQ ── */
.faq-list { max-width: 800px; margin-top: 20px; }
.faq-item { border-bottom: 1px solid var(--color-border); }
.faq-question {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
  cursor: pointer;
  font-weight: 600;
  color: var(--color-text);
  font-size: 15px;
  font-family: var(--font-body);
  background: none;
  border: none;
  width: 100%;
  text-align: left;
  transition: color 0.2s ease;
}
.faq-question.open { color: var(--color-primary); }
.faq-question:hover { color: var(--color-primary); }
.faq-arrow {
  flex-shrink: 0;
  margin-left: 12px;
  color: var(--color-muted);
  font-size: 14px;
}
.faq-answer {
  display: none;
  padding: 0 0 16px;
  font-size: 14px;
  color: var(--color-muted);
  line-height: 1.8;
}
.faq-answer.open { display: block; }

/* ── How-To Steps ── */
.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 28px;
}
.step-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 10px;
  padding: 28px 20px;
  text-align: center;
}
.step-num {
  font-family: var(--font-heading);
  font-size: 48px;
  color: var(--color-primary);
  opacity: 0.35;
  line-height: 1;
  margin-bottom: 12px;
}
.step-title {
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 8px;
}
.step-desc {
  font-size: 13px;
  color: var(--color-muted);
  line-height: 1.6;
}

/* ── Article Prose Overrides ── */
.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0 28px;
  font-size: 14px;
}
.prose th, .prose td {
  padding: 10px 14px;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}
.prose th {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--color-muted);
  background: var(--color-surface);
}
.prose td { color: var(--color-text); }

/* ── Related Tools ── */
.related-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 28px;
}

/* ── Field Error ── */
.field-error-msg {
  display: none;
  font-size: 11px;
  color: var(--color-primary);
  margin-top: 4px;
}
.field-error-msg.visible { display: block; }

/* ── Ad Placeholders ── */
.ad-placeholder {
  background: var(--color-surface2);
  border: 2px dashed var(--color-border);
  border-radius: 6px;
  display: block;
  margin: 28px auto;
}
.ad-leaderboard { width: 728px; height: 90px; max-width: 100%; }
.ad-rectangle { width: 300px; height: 250px; }

/* ── Responsive ── */
@media (max-width: 768px) {
  .result-grid { grid-template-columns: 1fr; }
  .ad-rectangle { float: none; margin: 28px auto; }
  .steps-grid { grid-template-columns: repeat(2, 1fr); }
  .related-grid { grid-template-columns: 1fr; }
  .standard-size-row { flex-direction: column; }
}
@media (max-width: 480px) {
  .ad-leaderboard { width: 320px; height: 50px; }
  .steps-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
}
@media print {
  .navbar, #footer, .ad-placeholder, .calc-tabs,
  .unit-toggle, .calculator-wrap, .wastage-group,
  .faq-item, section:not(.results-section),
  .btn { display: none !important; }
  .result-box { display: block !important; border: 1px solid #ccc; }
}