.bmi {
    --bmi-accent: #10b981;
    --bmi-bg: rgba(255, 255, 255, 0.9);
    --bmi-bg-left: rgba(248, 250, 252, 0.6);
    --bmi-border: rgba(226, 232, 240, 0.8);
    --bmi-text: #1e293b;
    --bmi-muted: #64748b;
    --bmi-slider-track: #e2e8f0;
    --bmi-step-bg: #fff;
    --bmi-step-border: #e2e8f0;

    display: grid;
    grid-template-columns: 1fr 1fr;
    background: var(--bmi-bg);
    border: 1px solid var(--bmi-border);
    border-radius: 2rem;
    overflow: hidden;
    max-width: 900px;
    margin: 2rem auto;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
  }

  .theme-dark .bmi {
    --bmi-bg: rgba(15, 23, 42, 0.85);
    --bmi-bg-left: rgba(30, 41, 59, 0.5);
    --bmi-border: rgba(51, 65, 85, 0.8);
    --bmi-text: #f8fafc;
    --bmi-muted: #94a3b8;
    --bmi-slider-track: #334155;
    --bmi-step-bg: #1e293b;
    --bmi-step-border: #334155;
  }

  .bmi[data-category="underweight"] { --bmi-accent: #3b82f6; }
  .bmi[data-category="normal"] { --bmi-accent: #10b981; }
  .bmi[data-category="overweight"] { --bmi-accent: #f59e0b; }
  .bmi[data-category="ob1"] { --bmi-accent: #f97316; }
  .bmi[data-category="ob2"] { --bmi-accent: #f43f5e; }
  .bmi[data-category="ob3"] { --bmi-accent: #dc2626; }

  .bmi__left {
    padding: 2.5rem;
    background: var(--bmi-bg-left);
    border-right: 1px solid var(--bmi-border);
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 2rem;
  }

  .bmi__field {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
  }

  .bmi__field-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
  }

  .bmi__field-label {
    font-size: 0.7rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--bmi-muted);
  }

  .bmi__field-value {
    font-size: 1.75rem;
    font-weight: 900;
    color: var(--bmi-text);
    letter-spacing: -1px;
  }

  .bmi__unit {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--bmi-muted);
  }

  .bmi__slider {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    appearance: none;
    background: var(--bmi-slider-track);
    cursor: pointer;
    accent-color: var(--bmi-accent);
    outline: none;
    border: none;
  }

  .bmi__step-btns {
    display: flex;
    gap: 0.75rem;
    justify-content: center;
  }

  .bmi__step {
    width: 2.75rem;
    height: 2.75rem;
    border-radius: 50%;
    background: var(--bmi-step-bg);
    border: 1px solid var(--bmi-step-border);
    color: var(--bmi-muted);
    font-size: 1.5rem;
    font-weight: 300;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.15s;
    line-height: 1;
  }

  .bmi__step:hover {
    border-color: var(--bmi-accent);
    color: var(--bmi-accent);
  }

  .bmi__right {
    padding: 2.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    gap: 0.75rem;
    position: relative;
    overflow: hidden;
  }

  .bmi__right::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(ellipse at 50% 0%, rgba(var(--bmi-accent-rgb, 16, 185, 129), 0.12) 0%, transparent 70%);
    transition: background 0.4s;
    pointer-events: none;
  }

  .bmi__your-bmi {
    font-size: 0.7rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--bmi-muted);
  }

  .bmi__value {
    font-size: 5rem;
    font-weight: 950;
    letter-spacing: -3px;
    color: var(--bmi-text);
    line-height: 1;
    transition: color 0.3s;
  }

  .bmi__category {
    display: inline-block;
    padding: 0.4rem 1.25rem;
    border-radius: 2rem;
    background: rgba(var(--bmi-accent-rgb, 16, 185, 129), 0.12);
    color: var(--bmi-accent);
    border: 1px solid rgba(var(--bmi-accent-rgb, 16, 185, 129), 0.25);
    font-weight: 800;
    font-size: 1rem;
    transition: all 0.3s;
  }

  .bmi__desc {
    font-size: 0.875rem;
    color: var(--bmi-muted);
    max-width: 22ch;
    line-height: 1.5;
    margin: 0;
    transition: color 0.3s;
  }

  .bmi__scale {
    width: 100%;
    margin-top: 0.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
  }

  .bmi__scale-bar {
    position: relative;
    height: 10px;
    border-radius: 5px;
    overflow: visible;
    display: flex;
  }

  .bmi__scale-seg {
    height: 100%;
    border-radius: 0;
  }

  .bmi__scale-seg--uw { width: 18.5%; background: #93c5fd; border-radius: 5px 0 0 5px; }
  .bmi__scale-seg--nw { width: 16.5%; background: #6ee7b7; }
  .bmi__scale-seg--ow { width: 12.5%; background: #fcd34d; }
  .bmi__scale-seg--ob { flex: 1; background: linear-gradient(to right, #fb923c, #f43f5e, #dc2626); border-radius: 0 5px 5px 0; }

  .bmi__scale-marker {
    position: absolute;
    top: -3px;
    width: 4px;
    height: 16px;
    background: var(--bmi-text);
    border-radius: 2px;
    box-shadow: 0 0 8px rgba(0, 0, 0, 0.3);
    transform: translateX(-50%);
    transition: left 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    left: 50%;
  }

  .bmi__scale-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.65rem;
    font-weight: 700;
    color: var(--bmi-muted);
    padding: 0 2px;
  }

  @media (max-width: 640px) {
    .bmi {
      grid-template-columns: 1fr;
      border-radius: 1.5rem;
      margin: 1rem 0;
    }

    .bmi__left {
      border-right: none;
      border-bottom: 1px solid var(--bmi-border);
      padding: 2rem 1.5rem;
    }

    .bmi__right {
      padding: 2rem 1.5rem;
    }

    .bmi__value {
      font-size: 4rem;
      letter-spacing: -2px;
    }
  }