/* ============================================
   Concrete Mix Ratio Calculator — Tool-specific styles
   Uses only CSS variables from /assets/css/style.css
   ============================================ */

/* ── Utility ── */
.hidden { display: none !important; }

/* ── Form Inputs ── */
.input-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: 8px;
}
.input-field,
.input-field[type="number"],
select.input-field {
  width: 100%;
  padding: 14px 16px;
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
  -moz-appearance: textfield;
  appearance: textfield;
  box-sizing: border-box;
}
.input-field::-webkit-inner-spin-button,
.input-field::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}
.input-field:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(244, 100, 10, 0.12);
}
.input-field::placeholder {
  color: var(--color-muted);
  opacity: 0.5;
}
select.input-field {
  cursor: pointer;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' fill='%238A8F9E'%3E%3Cpath d='M1 1l5 5 5-5'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 16px center;
  padding-right: 40px;
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
}
.input-hint {
  display: block;
  font-size: 12px;
  color: var(--color-muted);
  margin-top: 6px;
  line-height: 1.4;
}
.input-group {
  margin-bottom: 20px;
}
.input-row-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 4px;
}
.input-row-3 {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 16px;
  margin-bottom: 4px;
}
@media (max-width: 480px) {
  .input-row-2,
  .input-row-3 {
    grid-template-columns: 1fr;
  }
}

/* ── Shape Tabs (rebar, etc.) ── */
.shape-tabs {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 28px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}
.shape-tabs::-webkit-scrollbar { display: none; }
.shape-tab {
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 500;
  color: var(--color-muted);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  padding: 12px 20px;
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition);
}
.shape-tab:hover { color: var(--color-text); }
.shape-tab.active {
  color: var(--color-text);
  border-bottom-color: var(--color-primary);
}
.shape-tab-icon {
  margin-right: 6px;
  font-size: 14px;
}

/* ── Card Header/Body ── */
.card-header {
  padding-bottom: 20px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--color-border);
}
.card-title {
  font-family: var(--font-heading);
  font-size: 26px;
  letter-spacing: 1px;
  color: var(--color-text);
  margin: 0;
}
.card-body {
  /* just a semantic container */
}

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

/* ── Trust Chips ── */
.trust-chips {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  margin-top: 20px;
}
.trust-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 1px;
  color: var(--color-muted);
}
.trust-chip-icon {
  color: var(--color-primary);
  font-weight: 700;
}

/* ── Mode Toggle (pill) ── */
.mode-toggle,
.unit-toggle {
  display: inline-flex;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  padding: 3px;
  margin-bottom: 28px;
}
.mode-toggle-btn,
.unit-toggle-btn {
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  padding: 9px 24px;
  border: none;
  border-radius: var(--radius-full);
  background: transparent;
  color: var(--color-muted);
  cursor: pointer;
  transition: all var(--transition);
  letter-spacing: 0.5px;
}
.mode-toggle-btn.active,
.unit-toggle-btn.active {
  background: var(--color-primary);
  color: var(--color-white);
  box-shadow: 0 2px 8px rgba(244, 100, 10, 0.3);
}
.mode-toggle-btn:hover:not(.active),
.unit-toggle-btn:hover:not(.active) {
  color: var(--color-text);
}

/* ── Input Panels ── */
.input-panel {
  display: none;
}
.input-panel.active {
  display: block;
}

/* ── Segmented Control (bag size, wastage) ── */
.seg-control {
  display: inline-flex;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 3px;
  gap: 2px;
}
.seg-btn {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  padding: 8px 18px;
  border: none;
  border-radius: 4px;
  background: transparent;
  color: var(--color-muted);
  cursor: pointer;
  transition: all var(--transition);
}
.seg-btn.active {
  background: var(--color-surface2);
  color: var(--color-text);
  box-shadow: 0 1px 4px rgba(0,0,0,0.15);
}
.seg-btn:hover:not(.active) {
  color: var(--color-text);
}

/* ── Advanced Section (collapsible) ── */
.advanced-toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  color: var(--color-muted);
  cursor: pointer;
  border: none;
  background: none;
  padding: 0;
  margin-top: 20px;
  transition: color var(--transition);
}
.advanced-toggle:hover {
  color: var(--color-text);
}
.advanced-toggle-arrow {
  transition: transform var(--transition);
}
.advanced-toggle.open .advanced-toggle-arrow {
  transform: rotate(90deg);
}
.advanced-body {
  display: none;
  padding-top: 16px;
}
.advanced-body.open {
  display: block;
}

/* ── Slider ── */
.range-wrap {
  position: relative;
  margin: 12px 0 8px;
}
.range-wrap input[type="range"] {
  width: 100%;
  height: 6px;
  -webkit-appearance: none;
  appearance: none;
  background: var(--color-surface2);
  border-radius: 3px;
  outline: none;
}
.range-wrap input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--color-primary);
  cursor: pointer;
  box-shadow: 0 2px 6px rgba(244, 100, 10, 0.3);
}
.range-wrap input[type="range"]::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--color-primary);
  cursor: pointer;
  border: none;
}
.range-value {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  color: var(--color-yellow);
}
.range-hint {
  font-size: 12px;
  color: var(--color-muted);
  margin-top: 4px;
}

/* ── Wastage Section ── */
.wastage-section {
  margin-top: 28px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
}

/* ── Calculate Button Row ── */
.calc-actions {
  margin-top: 28px;
}

/* ── Results Box ── */
.results-box {
  background: var(--color-surface2);
  border-left: 3px solid var(--color-yellow);
  border-radius: 10px;
  padding: 28px;
  margin-top: 36px;
  display: none;
}
.results-box.visible {
  display: block;
}
.results-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.result-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 20px;
  transition: border-color var(--transition);
}
.result-card:hover {
  border-color: var(--color-border-hover);
}
.result-card.primary {
  border-left: 3px solid var(--color-primary);
}
.result-card.full-width {
  grid-column: 1 / -1;
}
.result-card-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: 8px;
}
.result-card-value {
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 600;
  color: var(--color-yellow);
  line-height: 1.1;
}
.result-card-unit {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-muted);
  margin-top: 4px;
}
.results-note {
  font-size: 12px;
  color: var(--color-muted);
  margin-top: 24px;
  padding-top: 18px;
  border-top: 1px solid var(--color-border);
  line-height: 1.7;
}

/* ── How-To Steps ── */
.how-to-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 28px;
}
.how-to-step {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 24px 18px;
  text-align: center;
}
.how-to-step-num {
  font-family: var(--font-heading);
  font-size: 28px;
  color: var(--color-primary);
  margin-bottom: 10px;
}
.how-to-step-title {
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 6px;
}
.how-to-step-desc {
  font-size: 13px;
  color: var(--color-muted);
  line-height: 1.5;
}

/* ── Article ── */
.article-content {
  max-width: 800px;
}
.article-content h2 {
  font-family: var(--font-heading);
  font-size: 26px;
  color: var(--color-text);
  margin: 40px 0 16px;
  letter-spacing: 1px;
}
.article-content h3 {
  font-family: var(--font-body);
  font-size: 18px;
  font-weight: 600;
  color: var(--color-text);
  margin: 28px 0 12px;
}
.article-content p {
  font-size: 15px;
  line-height: 1.8;
  color: var(--color-muted);
  margin-bottom: 16px;
}
.article-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0 28px;
  font-size: 14px;
}
.article-content th,
.article-content td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}
.article-content th {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--color-muted);
  background: var(--color-surface);
}
.article-content td {
  color: var(--color-text);
}

/* ── FAQ Accordion ── */
.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;
  width: 100%;
  padding: 20px 0;
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 600;
  color: var(--color-text);
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  transition: color var(--transition);
}
.faq-question:hover {
  color: var(--color-primary);
}
.faq-question.active {
  color: var(--color-primary);
}
.faq-arrow {
  font-size: 14px;
  color: var(--color-muted);
  flex-shrink: 0;
  margin-left: 16px;
  transition: transform var(--transition);
}
.faq-answer {
  display: none;
  padding: 0 0 20px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--color-muted);
}
.faq-answer.open {
  display: block;
}

/* ── Related Tools ── */
.related-tools-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 28px;
}
.tool-card {
  display: block;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 28px 20px;
  text-decoration: none;
  transition: border-color var(--transition);
}
.tool-card:hover {
  border-color: var(--color-primary);
}
.tool-card-icon {
  font-size: 28px;
  margin-bottom: 12px;
}
.tool-card-name {
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 6px;
}
.tool-card-desc {
  font-size: 13px;
  color: var(--color-muted);
  line-height: 1.5;
}
.tool-card-arrow {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-primary);
  margin-top: 12px;
  letter-spacing: 1px;
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .results-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .how-to-steps {
    grid-template-columns: repeat(2, 1fr);
  }
  .related-tools-grid {
    grid-template-columns: 1fr;
  }
}
@media (max-width: 480px) {
  .ad-placeholder.ad-leaderboard { width: 320px; height: 50px; }
  .results-grid {
    grid-template-columns: 1fr;
  }
  .how-to-steps {
    grid-template-columns: 1fr;
  }
  .mode-toggle,
  .unit-toggle {
    flex-wrap: wrap;
  }
  .seg-control {
    flex-wrap: wrap;
  }
  .result-card-value {
    font-size: 22px;
  }
}