:root {
    --bg: #0a0a0f;
    --surface: #13131a;
    --surface2: #1c1c27;
    --border: #2a2a3d;
    --accent: #00e5a0;
    --accent2: #5b8cff;
    --accent3: #ff6b6b;
    --text: #e8e8f0;
    --text-muted: #6b6b8a;
    --text-dim: #3a3a55;
  }

  * { margin: 0; padding: 0; box-sizing: border-box; }

  body {
    background: var(--bg);
    color: var(--text);
    font-family: 'DM Sans', sans-serif;
    min-height: 100vh;
    overflow-x: hidden;
  }

  /* ── GOOGLE ADS BANNER ── */
  .ads-banner {
    width: 100%;
    background: linear-gradient(90deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0 20px;
    position: relative;
    overflow: hidden;
    min-height: 90px;
  }

  .ads-banner::before {
    content: '';
    position: absolute;
    inset: 0;
    background: repeating-linear-gradient(
      45deg,
      transparent,
      transparent 40px,
      rgba(255,255,255,0.01) 40px,
      rgba(255,255,255,0.01) 80px
    );
  }

  .ads-label {
    position: absolute;
    top: 6px;
    left: 10px;
    font-size: 9px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-family: 'DM Mono', monospace;
  }

  /* Google Ad slot placeholder — vervang door echte adcode */
  .ads-slot {
    width: 728px;
    height: 90px;
    max-width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px dashed var(--border);
    border-radius: 4px;
    position: relative;
    z-index: 1;
  }

  /* Uncomment onderstaande block en vervang data-ad-* door jouw Google Ads waarden */
  /*
  .ads-slot ins {
    display: block;
    width: 728px;
    height: 90px;
  }
  */

  .ads-placeholder-text {
    font-size: 11px;
    color: var(--text-dim);
    font-family: 'DM Mono', monospace;
    text-align: center;
    line-height: 1.6;
  }

  .ads-placeholder-text strong {
    color: var(--text-muted);
    display: block;
    margin-bottom: 4px;
  }

  /* ── HEADER ── */
  header {
    padding: 48px 24px 24px;
    text-align: center;
    position: relative;
  }

  .header-grid {
    position: absolute;
    inset: 0;
    background-image:
      linear-gradient(var(--text-dim) 1px, transparent 1px),
      linear-gradient(90deg, var(--text-dim) 1px, transparent 1px);
    background-size: 40px 40px;
    opacity: 0.3;
    mask-image: radial-gradient(ellipse 80% 100% at 50% 0%, black 40%, transparent 80%);
  }

  .logo {
    font-family: 'Bebas Neue', sans-serif;
    font-size: clamp(42px, 8vw, 80px);
    letter-spacing: 4px;
    line-height: 1;
    position: relative;
    z-index: 1;
  }

  .logo span { color: var(--accent); }

  .tagline {
    font-size: 13px;
    color: var(--text-muted);
    letter-spacing: 3px;
    text-transform: uppercase;
    margin-top: 8px;
    position: relative;
    z-index: 1;
    font-family: 'DM Mono', monospace;
  }

  /* ── TABS ── */
  .tabs-wrapper {
    display: flex;
    justify-content: center;
    padding: 32px 24px 0;
    gap: 8px;
    flex-wrap: wrap;
  }

  .tab-btn {
    background: var(--surface);
    border: 1px solid var(--border);
    color: var(--text-muted);
    padding: 10px 22px;
    border-radius: 40px;
    cursor: pointer;
    font-family: 'DM Sans', sans-serif;
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 0.5px;
    transition: all 0.2s;
  }

  .tab-btn:hover { border-color: var(--accent2); color: var(--text); }

  .tab-btn.active {
    background: var(--accent);
    border-color: var(--accent);
    color: var(--bg);
    font-weight: 600;
  }

  /* ── MAIN CONTENT ── */
  main {
    max-width: 860px;
    margin: 32px auto 80px;
    padding: 0 24px;
  }

  .calculator-panel {
    display: none;
    animation: fadeUp 0.3s ease;
  }

  .calculator-panel.active { display: block; }

  @keyframes fadeUp {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
  }

  /* ── UNIT SELECTOR ── */
  .unit-selector {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-bottom: 28px;
  }

  .unit-btn {
    background: var(--surface);
    border: 1px solid var(--border);
    color: var(--text-muted);
    padding: 7px 16px;
    border-radius: 6px;
    cursor: pointer;
    font-family: 'DM Mono', monospace;
    font-size: 12px;
    transition: all 0.15s;
  }

  .unit-btn:hover { border-color: var(--accent2); color: var(--text); }
  .unit-btn.active { background: var(--surface2); border-color: var(--accent2); color: var(--accent2); }

  /* ── CALC CARD ── */
  .calc-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 32px;
    position: relative;
    overflow: hidden;
  }

  .calc-card::before {
    content: '';
    position: absolute;
    top: -1px; left: 20px; right: 20px;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--accent), transparent);
    border-radius: 2px;
  }

  .fields-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 24px;
  }

  .field-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
  }

  .field-label {
    font-size: 11px;
    font-family: 'DM Mono', monospace;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1.5px;
    display: flex;
    align-items: center;
    gap: 8px;
  }

  .field-label .unit-tag {
    background: var(--surface2);
    padding: 2px 8px;
    border-radius: 4px;
    color: var(--accent2);
    font-size: 10px;
  }

  .field-row {
    display: flex;
    align-items: stretch;
    border: 1px solid var(--border);
    border-radius: 10px;
    overflow: hidden;
    transition: border-color 0.2s;
    background: var(--bg);
  }

  .field-row:focus-within { border-color: var(--accent); }
  .field-row.target { border-color: var(--accent3); background: rgba(255,107,107,0.04); }
  .field-row.target:focus-within { border-color: var(--accent3); }

  .field-row input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    padding: 14px 16px;
    color: var(--text);
    font-family: 'DM Mono', monospace;
    font-size: 20px;
    font-weight: 500;
    width: 100%;
  }

  .field-row input::placeholder { color: var(--text-dim); font-size: 16px; }

  .field-row input.result-field {
    color: var(--accent);
  }

  .field-row.target input.result-field { color: var(--accent3); }

  .field-clear {
    background: none;
    border: none;
    border-left: 1px solid var(--border);
    color: var(--text-dim);
    padding: 0 14px;
    cursor: pointer;
    font-size: 16px;
    transition: color 0.15s;
    font-family: 'DM Sans', sans-serif;
  }

  .field-clear:hover { color: var(--accent3); }

  /* time input special */
  .time-inputs {
    display: flex;
    align-items: center;
    gap: 2px;
    flex: 1;
    padding: 0 4px;
  }

  .time-inputs input {
    text-align: center;
    padding: 14px 6px;
    font-size: 20px;
    min-width: 0;
  }

  .time-sep {
    color: var(--text-muted);
    font-family: 'DM Mono', monospace;
    font-size: 20px;
    font-weight: 500;
    flex-shrink: 0;
  }

  /* ── SOLVE BUTTONS ── */
  .solve-section {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 24px;
    align-items: center;
  }

  .solve-label {
    font-size: 11px;
    color: var(--text-muted);
    font-family: 'DM Mono', monospace;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-right: 4px;
  }

  .solve-btn {
    background: var(--surface2);
    border: 1px solid var(--border);
    color: var(--text-muted);
    padding: 9px 18px;
    border-radius: 8px;
    cursor: pointer;
    font-family: 'DM Sans', sans-serif;
    font-size: 13px;
    font-weight: 500;
    transition: all 0.2s;
  }

  .solve-btn:hover, .solve-btn.active {
    background: var(--accent);
    border-color: var(--accent);
    color: var(--bg);
    font-weight: 600;
  }

  /* ── RESULT ── */
  .result-banner {
    background: linear-gradient(135deg, var(--surface2), var(--bg));
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 20px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
    min-height: 70px;
    transition: all 0.3s;
  }

  .result-banner.has-result {
    border-color: var(--accent);
    background: linear-gradient(135deg, rgba(0,229,160,0.06), var(--bg));
  }

  .result-banner.has-result.speed-result { border-color: var(--accent2); background: linear-gradient(135deg, rgba(91,140,255,0.06), var(--bg)); }
  .result-banner.has-result.time-result { border-color: var(--accent3); background: linear-gradient(135deg, rgba(255,107,107,0.06), var(--bg)); }

  .result-label-main {
    font-size: 11px;
    font-family: 'DM Mono', monospace;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 4px;
  }

  .result-value-main {
    font-family: 'Bebas Neue', sans-serif;
    font-size: 36px;
    letter-spacing: 2px;
    color: var(--accent);
    line-height: 1;
  }

  .has-result.speed-result .result-value-main { color: var(--accent2); }
  .has-result.time-result .result-value-main { color: var(--accent3); }

  .result-extras {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
  }

  .result-extra {
    text-align: center;
  }

  .result-extra-label {
    font-size: 9px;
    font-family: 'DM Mono', monospace;
    color: var(--text-dim);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 2px;
  }

  .result-extra-val {
    font-family: 'DM Mono', monospace;
    font-size: 14px;
    color: var(--text-muted);
    font-weight: 500;
  }

  /* ── SPLIT TABLE ── */
  .split-section {
    margin-top: 24px;
  }

  .split-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 12px;
  }

  .split-title {
    font-size: 11px;
    font-family: 'DM Mono', monospace;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1.5px;
  }

  .split-table {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 8px;
  }

  .split-item {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 10px 14px;
    display: flex;
    flex-direction: column;
    gap: 3px;
  }

  .split-dist {
    font-size: 10px;
    font-family: 'DM Mono', monospace;
    color: var(--text-dim);
    text-transform: uppercase;
  }

  .split-time {
    font-family: 'DM Mono', monospace;
    font-size: 16px;
    font-weight: 500;
    color: var(--text);
  }

  /* ── CONVERSIONS GRID ── */
  .conversions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 8px;
    margin-top: 20px;
  }

  .conv-item {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 12px 14px;
  }

  .conv-unit {
    font-size: 10px;
    font-family: 'DM Mono', monospace;
    color: var(--text-dim);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 4px;
  }

  .conv-val {
    font-family: 'DM Mono', monospace;
    font-size: 18px;
    font-weight: 500;
    color: var(--accent);
  }

  .conv-desc {
    font-size: 10px;
    color: var(--text-muted);
    margin-top: 2px;
  }

  /* ── ERROR ── */
  .error-msg {
    color: var(--accent3);
    font-size: 12px;
    font-family: 'DM Mono', monospace;
    padding: 8px 0;
    min-height: 24px;
  }

  /* ── FOOTER ── */
  footer {
    text-align: center;
    padding: 40px 24px;
    border-top: 1px solid var(--border);
    color: var(--text-dim);
    font-size: 12px;
    font-family: 'DM Mono', monospace;
  }

  @media (max-width: 600px) {
    .calc-card { padding: 20px 16px; }
    .fields-grid { grid-template-columns: 1fr; }
    .result-banner { flex-direction: column; align-items: flex-start; }
  }

  /* ══════════════════════════════════════
     INFO SECTIONS
  ══════════════════════════════════════ */
  .info-section {
    border-top: 1px solid var(--border);
    padding: 64px 0 0;
  }

  .info-inner {
    max-width: 860px;
    margin: 0 auto;
    padding: 0 24px 64px;
  }

  .section-eyebrow {
    font-family: 'DM Mono', monospace;
    font-size: 11px;
    letter-spacing: 3px;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 12px;
  }

  .section-title {
    font-family: 'Bebas Neue', sans-serif;
    font-size: clamp(32px, 5vw, 52px);
    letter-spacing: 2px;
    line-height: 1;
    margin-bottom: 16px;
    color: var(--text);
  }

  .section-title span { color: var(--accent2); }

  .section-intro {
    font-size: 15px;
    color: var(--text-muted);
    line-height: 1.7;
    max-width: 600px;
    margin-bottom: 36px;
  }

  /* ── CONVERTER ── */
  .converter-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 32px;
    position: relative;
    overflow: hidden;
  }

  .converter-card::before {
    content: '';
    position: absolute;
    top: -1px; left: 20px; right: 20px;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--accent2), transparent);
  }

  .conv-twin {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 20px;
    align-items: start;
    margin-bottom: 32px;
  }

  .conv-field-wrap {
    min-width: 0;
    overflow: hidden;
  }

  .conv-field-label {
    font-size: 11px;
    font-family: 'DM Mono', monospace;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 8px;
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 6px;
  }

  .conv-tag {
    background: var(--surface2);
    padding: 2px 7px;
    border-radius: 4px;
    color: var(--accent2);
    font-size: 10px;
  }

  .conv-field-row {
    display: flex;
    align-items: stretch;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    overflow: hidden;
    transition: border-color 0.2s;
  }

  .conv-field-row:focus-within { border-color: var(--accent2); }

  .conv-field-row input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    padding: 16px 12px;
    color: var(--text);
    font-family: 'DM Mono', monospace;
    font-size: 22px;
    font-weight: 500;
    min-width: 0;
    width: 0;
  }

  .conv-field-row input::placeholder { color: var(--text-dim); font-size: 16px; }

  .conv-unit-badge {
    background: var(--surface2);
    border-left: 1px solid var(--border);
    padding: 0 14px;
    display: flex;
    align-items: center;
    font-family: 'DM Mono', monospace;
    font-size: 12px;
    color: var(--text-muted);
    white-space: nowrap;
  }

  .conv-arrow-wrap {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding-top: 20px;
  }

  .conv-arrow {
    font-size: 28px;
    color: var(--accent2);
    line-height: 1;
  }

  .conv-factor {
    font-size: 10px;
    font-family: 'DM Mono', monospace;
    color: var(--text-dim);
    white-space: nowrap;
  }

  .conv-ref-title {
    font-size: 11px;
    font-family: 'DM Mono', monospace;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 12px;
  }

  .conv-ref-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
    gap: 8px;
  }

  .conv-ref-item {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 10px 12px;
  }

  .conv-ref-mph {
    font-family: 'DM Mono', monospace;
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 2px;
  }

  .conv-ref-kmh {
    font-family: 'DM Mono', monospace;
    font-size: 18px;
    font-weight: 500;
    color: var(--accent2);
  }

  .conv-ref-label {
    font-size: 10px;
    color: var(--text-dim);
    margin-top: 2px;
  }

  @media (max-width: 600px) {
    .conv-twin { grid-template-columns: 1fr; }
    .conv-arrow-wrap { flex-direction: row; padding-top: 0; }
  }

  /* ── FORMULA ── */
  .formula-box {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 28px 24px 20px;
    margin-bottom: 32px;
  }

  .formula-trio {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 16px;
    margin-bottom: 16px;
  }

  .formula-item {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 18px 20px;
    text-align: center;
  }

  .formula-item.highlight {
    border-color: var(--accent);
    background: rgba(0,229,160,0.04);
  }

  .fi-label {
    font-size: 10px;
    font-family: 'DM Mono', monospace;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 8px;
  }

  .fi-formula {
    font-family: 'Bebas Neue', sans-serif;
    font-size: 30px;
    letter-spacing: 2px;
    color: var(--accent);
    margin-bottom: 6px;
  }

  .formula-item:not(.highlight) .fi-formula { color: var(--text); }

  .fi-desc {
    font-size: 11px;
    color: var(--text-dim);
    font-family: 'DM Mono', monospace;
  }

  .formula-legend {
    font-family: 'DM Mono', monospace;
    font-size: 12px;
    color: var(--text-muted);
    text-align: center;
  }

  .formula-legend code {
    background: var(--surface2);
    padding: 2px 6px;
    border-radius: 4px;
    color: var(--accent);
    font-size: 13px;
  }

  /* ── EXAMPLES ── */
  .examples-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 16px;
    margin-bottom: 36px;
  }

  .example-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 22px 24px;
  }

  .ex-sport {
    font-size: 12px;
    font-family: 'DM Mono', monospace;
    color: var(--text-muted);
    margin-bottom: 6px;
  }

  .ex-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 16px;
    line-height: 1.4;
  }

  .ex-steps {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 16px;
  }

  .ex-step {
    display: flex;
    gap: 10px;
    align-items: flex-start;
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.5;
  }

  .ex-num {
    background: var(--surface2);
    border: 1px solid var(--border);
    color: var(--accent2);
    font-family: 'DM Mono', monospace;
    font-size: 11px;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    margin-top: 1px;
  }

  .ex-step strong { color: var(--text); }

  .ex-answer {
    background: var(--bg);
    border: 1px solid var(--border);
    border-left: 3px solid var(--accent);
    border-radius: 6px;
    padding: 10px 14px;
    font-size: 13px;
    color: var(--text-muted);
    font-family: 'DM Mono', monospace;
  }

  .ex-answer strong { color: var(--accent); }

  /* ── INFO BLOCKS ── */
  .info-block {
    display: flex;
    gap: 20px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 24px;
    margin-bottom: 16px;
  }

  .ib-icon {
    font-size: 28px;
    flex-shrink: 0;
    margin-top: 2px;
  }

  .ib-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 8px;
  }

  .ib-text {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 16px;
  }

  .ib-text code {
    background: var(--surface2);
    padding: 1px 5px;
    border-radius: 3px;
    color: var(--accent);
    font-family: 'DM Mono', monospace;
    font-size: 12px;
  }

  /* ── PACE TABLE ── */
  .pace-table {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    overflow: hidden;
    font-family: 'DM Mono', monospace;
    font-size: 12px;
  }

  .pt-header {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(80px, 1fr));
    gap: 0;
    background: var(--surface2);
    padding: 8px 14px;
    color: var(--text-muted);
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 1px;
    border-bottom: 1px solid var(--border);
  }

  .pt-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(80px, 1fr));
    padding: 9px 14px;
    border-bottom: 1px solid var(--border);
    color: var(--text-muted);
    transition: background 0.15s;
  }

  .pt-row:last-child { border-bottom: none; }
  .pt-row:hover { background: var(--surface2); }
  .pt-row span:first-child { color: var(--text); }


  /* TOP NAV */
  .top-nav {
    display:flex;justify-content:center;gap:0;flex-wrap:wrap;
    border-bottom:1px solid var(--border);background:var(--bg);
    position:sticky;top:0;z-index:100;padding:0 24px;
  }
  .top-nav-btn {
    background:transparent;border:none;border-bottom:3px solid transparent;
    color:var(--text-muted);padding:16px 28px 18px;cursor:pointer;
    font-family:'DM Sans',sans-serif;font-size:14px;font-weight:500;
    letter-spacing:0.3px;transition:all 0.2s;display:flex;align-items:center;gap:7px;margin-bottom:-1px;
  }
  .top-nav-btn:hover{color:var(--text);border-bottom-color:var(--border);}
  .top-nav-btn.active{color:var(--accent);border-bottom-color:var(--accent);font-weight:600;}
  .tnb-icon{font-size:16px;}
  .section-wrapper{display:none;}.section-wrapper.active{display:block;}
  /* CONVERTER TABS */
  .conv-tabs{display:flex;gap:8px;flex-wrap:wrap;padding:28px 24px 0;max-width:860px;margin:0 auto;}
  .conv-tab-btn{background:var(--surface);border:1px solid var(--border);color:var(--text-muted);
    padding:9px 20px;border-radius:40px;cursor:pointer;font-family:'DM Sans',sans-serif;
    font-size:13px;font-weight:500;transition:all 0.2s;}
  .conv-tab-btn:hover{border-color:var(--accent2);color:var(--text);}
  .conv-tab-btn.active{background:var(--accent2);border-color:var(--accent2);color:#fff;font-weight:600;}
  .conv-panel{display:none;animation:fadeUp 0.3s ease;}.conv-panel.active{display:block;}
  /* ALL-UNITS grid */
  .au-grid-wrap{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:12px;margin-bottom:24px;}
  /* GIDS typography */
  .gids-section{max-width:860px;margin:0 auto;padding:48px 24px 80px;}
  .article-lead{font-size:17px;color:var(--text);line-height:1.8;margin-bottom:20px;}
  .article-body{font-size:14px;color:var(--text-muted);line-height:1.85;margin-bottom:16px;}
  .article-body strong{color:var(--text);}.article-body em{color:var(--accent);font-style:normal;}
  .article-h2{font-family:'Bebas Neue',sans-serif;font-size:clamp(24px,4vw,38px);letter-spacing:2px;
    color:var(--text);margin:48px 0 16px;padding-top:48px;border-top:1px solid var(--border);}
  .article-h3{font-size:16px;font-weight:600;color:var(--text);margin:28px 0 10px;}
  .highlight-box{background:var(--surface);border:1px solid var(--border);
    border-left:3px solid var(--accent3);border-radius:10px;padding:20px 24px;margin:24px 0;}
  .highlight-box.tip{border-left-color:var(--accent);}
  .highlight-box.info{border-left-color:var(--accent2);}
  .hb-label{font-family:'DM Mono',monospace;font-size:10px;text-transform:uppercase;
    letter-spacing:1.5px;color:var(--accent3);margin-bottom:8px;}
  .highlight-box.tip .hb-label{color:var(--accent);}
  .highlight-box.info .hb-label{color:var(--accent2);}
  .hb-text{font-size:14px;color:var(--text-muted);line-height:1.75;}
  .hb-text strong{color:var(--text);}
  .strategy-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:14px;margin:24px 0;}
  .strategy-card{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:20px;}
  .sc-icon{font-size:24px;margin-bottom:10px;}.sc-title{font-size:14px;font-weight:600;color:var(--text);margin-bottom:8px;}
  .sc-text{font-size:12px;color:var(--text-muted);line-height:1.7;}
  .sc-verdict{margin-top:10px;font-size:11px;font-family:'DM Mono',monospace;padding:4px 10px;border-radius:20px;display:inline-block;}
  .sc-verdict.good{background:rgba(0,229,160,0.1);color:var(--accent);}
  .sc-verdict.bad{background:rgba(255,107,107,0.1);color:var(--accent3);}
  .sc-verdict.neutral{background:var(--surface2);color:var(--text-muted);}
  .race-zones{background:var(--surface);border:1px solid var(--border);border-radius:12px;overflow:hidden;margin:24px 0;}
  .rz-header{display:grid;gap:0;background:var(--surface2);padding:10px 16px;
    font-family:'DM Mono',monospace;font-size:10px;color:var(--text-muted);
    text-transform:uppercase;letter-spacing:1px;border-bottom:1px solid var(--border);}
  .rz-row{display:grid;gap:0;padding:11px 16px;border-bottom:1px solid var(--border);
    font-size:13px;transition:background 0.15s;}
  .rz-row:last-child{border-bottom:none;}.rz-row:hover{background:var(--surface2);}
  .rz-row span{color:var(--text-muted);font-family:'DM Mono',monospace;font-size:12px;}
  .rz-row span:first-child{color:var(--text);font-weight:500;}
  .article-quote{border-left:3px solid var(--accent2);padding:12px 20px;margin:28px 0;
    font-size:16px;color:var(--text);font-style:italic;line-height:1.7;}
  .article-quote cite{display:block;font-size:11px;font-style:normal;color:var(--text-dim);
    font-family:'DM Mono',monospace;margin-top:8px;text-transform:uppercase;letter-spacing:1px;}
  @media(max-width:600px){
    .rz-header,.rz-row{grid-template-columns:2fr 1fr 2fr!important;}
    .rz-header span:nth-child(3),.rz-row span:nth-child(3){display:none;}
  }

  /* ── CALC INFO BLOCKS ── */
  .calc-info {
    margin-top: 20px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
  }

  .calc-info-toggle {
    width: 100%;
    background: none;
    border: none;
    padding: 14px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
    color: var(--text-muted);
    font-family: 'DM Sans', sans-serif;
    font-size: 13px;
    font-weight: 500;
    transition: background 0.15s;
  }

  .calc-info-toggle:hover { background: var(--surface2); }

  .calc-info-toggle .cit-left {
    display: flex;
    align-items: center;
    gap: 10px;
  }

  .calc-info-toggle .cit-icon {
    font-size: 16px;
  }

  .calc-info-toggle .cit-arrow {
    font-size: 12px;
    transition: transform 0.2s;
    color: var(--text-dim);
  }

  .calc-info.open .cit-arrow { transform: rotate(180deg); }

  .calc-info-body {
    display: none;
    padding: 0 20px 20px;
    border-top: 1px solid var(--border);
  }

  .calc-info.open .calc-info-body { display: block; }

  .cib-formula {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 14px 18px;
    margin: 16px 0 12px;
    font-family: 'DM Mono', monospace;
    font-size: 13px;
    color: var(--text-muted);
    display: flex;
    flex-wrap: wrap;
    gap: 8px 20px;
  }

  .cib-formula span { color: var(--text); }
  .cib-formula em { color: var(--accent); font-style: normal; }

  .cib-example {
    background: var(--bg);
    border-left: 3px solid var(--accent);
    border-radius: 6px;
    padding: 12px 16px;
    margin-top: 12px;
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.7;
  }

  .cib-example strong { color: var(--text); }
  .cib-example em { color: var(--accent); font-style: normal; }

  .cib-text {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.7;
    margin-top: 12px;
  }

  .cib-text strong { color: var(--text); }

  /* ══════════════════════════════════════
     HOMEPAGE
  ══════════════════════════════════════ */
  .home-hero {
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    position: relative;
    overflow: hidden;
  }

  .home-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
      linear-gradient(var(--text-dim) 1px, transparent 1px),
      linear-gradient(90deg, var(--text-dim) 1px, transparent 1px);
    background-size: 48px 48px;
    opacity: 0.18;
    mask-image: radial-gradient(ellipse 80% 100% at 50% 0%, black 30%, transparent 80%);
  }

  .home-hero-inner {
    max-width: 860px;
    margin: 0 auto;
    padding: 64px 24px 40px;
    position: relative;
    z-index: 1;
  }

  .home-eyebrow {
    font-family: 'DM Mono', monospace;
    font-size: 11px;
    letter-spacing: 3px;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 16px;
  }

  .home-title {
    font-family: 'Bebas Neue', sans-serif;
    font-size: clamp(52px, 10vw, 96px);
    letter-spacing: 3px;
    line-height: 0.95;
    color: var(--text);
    margin-bottom: 20px;
  }

  .home-title span { color: var(--accent); }

  .home-lead {
    font-size: 16px;
    color: var(--text-muted);
    line-height: 1.75;
    max-width: 560px;
    margin-bottom: 32px;
  }

  .home-cta-row {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
  }

  .home-cta-btn {
    padding: 14px 28px;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    font-family: 'DM Sans', sans-serif;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.2s;
    letter-spacing: 0.3px;
  }

  .home-cta-btn.primary {
    background: var(--accent);
    color: var(--bg);
  }

  .home-cta-btn.primary:hover { filter: brightness(1.1); transform: translateY(-1px); }

  .home-cta-btn.secondary {
    background: var(--surface);
    color: var(--text-muted);
    border: 1px solid var(--border);
  }

  .home-cta-btn.secondary:hover { border-color: var(--accent2); color: var(--text); }

  .home-hero-stats {
    max-width: 860px;
    margin: 0 auto;
    padding: 0 24px 48px;
    display: flex;
    gap: 0;
    position: relative;
    z-index: 1;
  }

  .home-stat {
    flex: 1;
    padding: 20px 0;
    border-right: 1px solid var(--border);
    text-align: center;
  }

  .home-stat:last-child { border-right: none; }

  .hs-num {
    display: block;
    font-family: 'Bebas Neue', sans-serif;
    font-size: 42px;
    letter-spacing: 2px;
    color: var(--accent);
    line-height: 1;
  }

  .hs-label {
    display: block;
    font-size: 11px;
    font-family: 'DM Mono', monospace;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-top: 4px;
  }

  /* ABOUT */
  .home-about {
    border-bottom: 1px solid var(--border);
  }

  .home-about-inner {
    max-width: 860px;
    margin: 0 auto;
    padding: 64px 24px;
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 48px;
    align-items: center;
  }

  .home-section-h2 {
    font-family: 'Bebas Neue', sans-serif;
    font-size: clamp(28px, 4vw, 44px);
    letter-spacing: 2px;
    color: var(--text);
    margin-bottom: 20px;
  }

  .home-about-text p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.8;
    margin-bottom: 14px;
  }

  .home-about-text p strong { color: var(--text); }

  .home-about-graphic {
    width: 160px;
    height: 160px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
  }

  .hag-ring {
    position: absolute;
    border-radius: 50%;
    border: 1px solid var(--border);
  }

  .hag-ring-1 { width: 160px; height: 160px; border-color: var(--accent); opacity: 0.3; animation: spin 20s linear infinite; }
  .hag-ring-2 { width: 120px; height: 120px; border-color: var(--accent2); opacity: 0.4; animation: spin 14s linear infinite reverse; }
  .hag-ring-3 { width: 80px; height: 80px; border-color: var(--accent3); opacity: 0.5; }

  @keyframes spin { from { transform: rotate(0deg); } to { transform: rotate(360deg); } }

  .hag-center { font-size: 40px; position: relative; z-index: 1; }

  /* CARDS */
  .home-cards-section {
    border-bottom: 1px solid var(--border);
  }

  .home-cards-inner {
    max-width: 860px;
    margin: 0 auto;
    padding: 64px 24px;
  }

  .home-cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 16px;
    margin-top: 32px;
  }

  .home-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 24px;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    flex-direction: column;
    gap: 10px;
  }

  .home-card:hover {
    border-color: var(--hc-color, var(--accent));
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.3);
  }

  .hc-header {
    display: flex;
    align-items: center;
    gap: 10px;
  }

  .hc-icon {
    font-size: 22px;
    line-height: 1;
  }

  .hc-tag {
    font-family: 'DM Mono', monospace;
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--hc-color, var(--accent));
    background: rgba(0,229,160,0.08);
    padding: 3px 10px;
    border-radius: 20px;
    border: 1px solid var(--hc-color, var(--accent));
    opacity: 0.8;
  }

  .hc-title {
    font-size: 17px;
    font-weight: 600;
    color: var(--text);
    line-height: 1.3;
  }

  .hc-text {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.7;
    flex: 1;
  }

  .hc-sports {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-top: 4px;
  }

  .hc-sports span {
    font-size: 11px;
    font-family: 'DM Mono', monospace;
    background: var(--surface2);
    padding: 3px 9px;
    border-radius: 4px;
    color: var(--text-muted);
  }

  .hc-cta {
    font-size: 12px;
    font-family: 'DM Mono', monospace;
    color: var(--hc-color, var(--accent));
    margin-top: 4px;
  }

  /* FORMULA SECTION */
  .home-formulas {
    border-bottom: 1px solid var(--border);
  }

  .home-formulas-inner {
    max-width: 860px;
    margin: 0 auto;
    padding: 64px 24px;
  }

  .home-formula-intro {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.7;
    max-width: 560px;
    margin-bottom: 32px;
  }

  .home-formula-trio {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
  }

  .hft-item {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 24px 20px;
    text-align: center;
  }

  .hft-label {
    font-size: 10px;
    font-family: 'DM Mono', monospace;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 12px;
  }

  .hft-formula {
    font-family: 'Bebas Neue', sans-serif;
    font-size: 36px;
    letter-spacing: 2px;
    color: var(--accent);
    margin-bottom: 10px;
  }

  .hft-example {
    font-size: 11px;
    font-family: 'DM Mono', monospace;
    color: var(--text-dim);
  }

  @media (max-width: 600px) {
    .home-about-inner { grid-template-columns: 1fr; }
    .home-about-graphic { display: none; }
    .home-hero-stats { gap: 0; }
    .hs-num { font-size: 32px; }
  }

  /* ══════════════════════════════════════
     MOBILE RESPONSIVE — comprehensive
  ══════════════════════════════════════ */

  /* ── Top nav: scrollable on mobile ── */
  @media (max-width: 640px) {
    .top-nav {
      overflow-x: auto;
      overflow-y: hidden;
      justify-content: flex-start;
      flex-wrap: nowrap;
      padding: 0 16px;
      -webkit-overflow-scrolling: touch;
      scrollbar-width: none;
    }
    .top-nav::-webkit-scrollbar { display: none; }
    .top-nav-btn {
      padding: 14px 16px 16px;
      font-size: 13px;
      white-space: nowrap;
      flex-shrink: 0;
    }
    .tnb-icon { display: none; }
  }

  /* ── Header ── */
  @media (max-width: 640px) {
    header { padding: 36px 16px 20px; }
    .tagline { font-size: 11px; letter-spacing: 2px; }
  }

  /* ── Ads banner ── */
  @media (max-width: 728px) {
    .ads-banner { min-height: 60px; }
    .ads-slot { width: 100%; max-width: 320px; height: 50px; }
  }

  /* ── Calc tabs ── */
  @media (max-width: 640px) {
    .tabs-wrapper {
      overflow-x: auto;
      flex-wrap: nowrap;
      justify-content: flex-start;
      padding: 20px 16px 0;
      -webkit-overflow-scrolling: touch;
      scrollbar-width: none;
    }
    .tabs-wrapper::-webkit-scrollbar { display: none; }
    .tab-btn {
      white-space: nowrap;
      flex-shrink: 0;
      padding: 9px 16px;
      font-size: 13px;
    }
    main { padding: 0 12px; margin-top: 20px; }
  }

  /* ── Unit selector ── */
  @media (max-width: 640px) {
    .unit-selector {
      overflow-x: auto;
      flex-wrap: nowrap;
      -webkit-overflow-scrolling: touch;
      scrollbar-width: none;
      padding-bottom: 4px;
    }
    .unit-selector::-webkit-scrollbar { display: none; }
    .unit-btn { white-space: nowrap; flex-shrink: 0; }
  }

  /* ── Calc card ── */
  @media (max-width: 640px) {
    .calc-card { padding: 16px 12px; border-radius: 12px; }
    .solve-section { flex-wrap: wrap; gap: 6px; }
    .solve-btn { font-size: 12px; padding: 8px 14px; }
    .fields-grid { grid-template-columns: 1fr; gap: 12px; }
    .field-row input { font-size: 18px; }
    .time-inputs input { font-size: 18px; }
    .result-banner { flex-direction: column; align-items: flex-start; gap: 8px; padding: 16px; }
    .result-value-main { font-size: 28px; }
    .result-extras { flex-wrap: wrap; gap: 12px; }
  }

  /* ── Split table ── */
  @media (max-width: 640px) {
    .split-table { grid-template-columns: repeat(2, 1fr); }
  }

  /* ── Conversions grid ── */
  @media (max-width: 640px) {
    .conversions-grid { grid-template-columns: repeat(2, 1fr); }
  }

  /* ── Calc info block ── */
  @media (max-width: 640px) {
    .calc-info { margin-top: 12px; }
    .cib-formula { font-size: 12px; flex-direction: column; gap: 6px; }
    .cib-example { font-size: 12px; }
  }

  /* ── Conv twin (converter card) ── */
  @media (max-width: 640px) {
    .conv-twin { grid-template-columns: 1fr; gap: 12px; }
    .conv-arrow-wrap { flex-direction: row; padding-top: 0; justify-content: center; }
    .conv-field-row input { font-size: 18px; padding: 12px; }
    .converter-card { padding: 16px; }
    .conv-ref-grid { grid-template-columns: repeat(2, 1fr); }
  }

  /* ── Conv tabs ── */
  @media (max-width: 640px) {
    .conv-tabs {
      overflow-x: auto;
      flex-wrap: nowrap;
      padding: 20px 16px 0;
      -webkit-overflow-scrolling: touch;
      scrollbar-width: none;
    }
    .conv-tabs::-webkit-scrollbar { display: none; }
    .conv-tab-btn { white-space: nowrap; flex-shrink: 0; font-size: 12px; padding: 8px 14px; }
    div[style*="max-width:860px;margin:0 auto;padding:0 24px 64px"] { padding: 0 12px 48px !important; }
  }

  /* ── Gids / article ── */
  @media (max-width: 640px) {
    .gids-section { padding: 32px 16px 60px; }
    .article-h2 { font-size: 26px; margin: 32px 0 12px; padding-top: 32px; }
    .article-h3 { font-size: 15px; }
    .article-lead { font-size: 15px; }
    .article-body { font-size: 13px; }
    .highlight-box { padding: 14px 16px; }
    .hb-text { font-size: 13px; }
    .strategy-grid { grid-template-columns: 1fr; }
    .race-zones { overflow-x: auto; }
    .rz-header, .rz-row {
      grid-template-columns: 1.8fr 1fr 2fr !important;
      font-size: 11px;
    }
    .rz-header span:nth-child(3), .rz-row span:nth-child(3) { display: none; }
    .article-quote { font-size: 14px; padding: 10px 14px; }
    .pace-table { font-size: 11px; }
    .pt-header, .pt-row { padding: 7px 10px; }
    .info-block { flex-direction: column; gap: 12px; }
    .ib-icon { font-size: 22px; }
    .examples-grid { grid-template-columns: 1fr; }
    .formula-trio { grid-template-columns: 1fr; }
  }

  /* ── Info sections ── */
  @media (max-width: 640px) {
    .info-section { padding-top: 40px; }
    .info-inner { padding: 0 16px 48px; }
    .section-title { font-size: clamp(28px, 6vw, 44px); }
    .section-intro { font-size: 14px; }
    .formula-box { padding: 16px 12px; }
    .formula-trio { gap: 10px; }
  }

  /* ── Homepage ── */
  @media (max-width: 640px) {
    .home-hero-inner { padding: 40px 16px 28px; }
    .home-title { font-size: clamp(44px, 13vw, 70px); }
    .home-lead { font-size: 14px; }
    .home-cta-row { flex-direction: column; }
    .home-cta-btn { width: 100%; text-align: center; }
    .home-hero-stats { padding: 0 16px 36px; }
    .hs-num { font-size: 30px; }
    .hs-label { font-size: 10px; }
    .home-about-inner { padding: 40px 16px; grid-template-columns: 1fr; gap: 24px; }
    .home-about-graphic { display: none; }
    .home-about-text p { font-size: 13px; }
    .home-cards-inner { padding: 40px 16px; }
    .home-section-h2 { font-size: clamp(24px, 6vw, 36px); }
    .home-cards-grid { grid-template-columns: 1fr; gap: 12px; }
    .home-card { padding: 18px; }
    .hc-title { font-size: 15px; }
    .hc-text { font-size: 12px; }
    .home-formulas-inner { padding: 40px 16px; }
    .home-formula-trio { grid-template-columns: 1fr; gap: 10px; }
    .hft-formula { font-size: 28px; }
  }

  /* ── Triathlon calculator ── */
  @media (max-width: 640px) {
    #tri-legs-grid { grid-template-columns: 1fr !important; gap: 12px !important; }
    .tri-solve-row { flex-wrap: wrap; }
    #tri-dist-btns {
      overflow-x: auto;
      flex-wrap: nowrap;
      -webkit-overflow-scrolling: touch;
      scrollbar-width: none;
    }
    #tri-dist-btns::-webkit-scrollbar { display: none; }
    #tri-dist-btns .unit-btn { white-space: nowrap; flex-shrink: 0; }
    #tri-format-btns .unit-btn { font-size: 12px; padding: 7px 12px; }
  }

  /* ── Result detail table (tri) ── */
  @media (max-width: 640px) {
    .race-zones [style*="grid-template-columns:1.5fr"] {
      grid-template-columns: 1.5fr 0.8fr 1fr !important;
    }
    .race-zones [style*="grid-template-columns:1.5fr"] span:nth-child(4),
    .race-zones [style*="grid-template-columns:1.5fr"] span:nth-child(5) { display: none; }
    .race-zones [style*="grid-template-columns:2fr 1.5fr"] {
      grid-template-columns: 2fr 1fr 1fr !important;
    }
    .race-zones [style*="grid-template-columns:2fr 1.5fr"] span:nth-child(4) { display: none; }
  }

  /* ── General ── */
  @media (max-width: 640px) {
    .section-eyebrow { font-size: 10px; letter-spacing: 2px; }
    footer { font-size: 11px; padding: 28px 16px; }
  }