.fiber-prep {
    width: 100%;
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
  }

  .profile-section {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
  }

  .profile-header {
    text-align: center;
  }

  .profile-title {
    font-size: 1.25rem;
    font-weight: 900;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-main);
    margin: 0 0 0.5rem;
  }

  .profile-desc {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin: 0;
  }

  .profile-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
  }

  .fiber-card {
    position: relative;
    display: flex;
    flex-direction: column;
    padding: 2rem;
    border-radius: 2rem;
    border: 2px solid var(--border-color);
    background: var(--bg-surface);
    text-align: left;
    cursor: pointer;
    overflow: hidden;
    transition: border-color 0.2s, box-shadow 0.2s;
  }

  .fiber-card:hover {
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
  }

  .fiber-card[data-fiber-type="protein"].active {
    border-color: #f59e0b;
    box-shadow: 0 0 0 3px rgba(245, 158, 11, 0.15);
  }

  .fiber-card[data-fiber-type="cellulosic"].active {
    border-color: #10b981;
    box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.15);
  }

  .card-bg-icon {
    position: absolute;
    top: 0;
    right: 0;
    padding: 2rem;
    opacity: 0.05;
    pointer-events: none;
    transition: opacity 0.2s;
  }

  .fiber-card:hover .card-bg-icon {
    opacity: 0.1;
  }

  .card-bg-icon svg {
    width: 9rem;
    height: 9rem;
  }

  .card-body {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    gap: 1rem;
  }

  .card-icon {
    width: 3.5rem;
    height: 3.5rem;
    border-radius: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .card-icon svg {
    width: 1.75rem;
    height: 1.75rem;
  }

  .card-icon-protein {
    background: rgba(245, 158, 11, 0.1);
    color: #f59e0b;
  }

  .card-icon-cellulosic {
    background: rgba(16, 185, 129, 0.1);
    color: #10b981;
  }

  .card-title {
    font-size: 1.125rem;
    font-weight: 900;
    text-transform: uppercase;
    color: var(--text-main);
    margin: 0 0 0.25rem;
  }

  .card-origin {
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin: 0 0 0.5rem;
  }

  .card-origin-protein {
    color: rgba(245, 158, 11, 0.7);
  }

  .card-origin-cellulosic {
    color: rgba(16, 185, 129, 0.7);
  }

  .card-desc {
    font-size: 0.875rem;
    color: var(--text-muted);
    line-height: 1.5;
    margin: 0;
  }

  .fiber-icon-list {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
  }

  .fiber-icon-item {
    width: 2rem;
    height: 2rem;
    border-radius: 0.5rem;
    background: var(--bg-page);
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .fiber-icon-item svg {
    width: 1rem;
    height: 1rem;
    color: var(--text-muted);
  }

  .tool-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }

  .calc-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-color);
    border-radius: 1.5rem;
    padding: 1.5rem;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
  }

  .calc-header {
    display: flex;
    align-items: center;
    gap: 1rem;
  }

  .calc-icon {
    width: 2.5rem;
    height: 2.5rem;
    border-radius: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
  }

  .calc-icon svg {
    width: 1.25rem;
    height: 1.25rem;
  }

  .calc-icon-green {
    background: rgba(16, 185, 129, 0.1);
    color: #10b981;
  }

  .calc-icon-orange {
    background: rgba(249, 115, 22, 0.1);
    color: #f97316;
  }

  .calc-icon-purple {
    background: rgba(139, 92, 246, 0.1);
    color: #8b5cf6;
  }

  .calc-title {
    font-size: 1rem;
    font-weight: 700;
    color: var(--text-main);
    margin: 0;
  }

  .wof-body {
    position: relative;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
  }

  .wof-overlay {
    position: absolute;
    inset: -0.5rem;
    z-index: 2;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(2px);
    border-radius: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 1.5rem;
    transition: opacity 0.5s;
  }

  .theme-dark .wof-overlay {
    background: rgba(15, 23, 42, 0.85);
  }

  .wof-overlay.hidden {
    display: none;
  }

  .ph-overlay {
    position: absolute;
    inset: -0.5rem;
    z-index: 2;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(2px);
    border-radius: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 1.5rem;
    transition: opacity 0.5s;
  }

  .theme-dark .ph-overlay {
    background: rgba(15, 23, 42, 0.85);
  }

  .ph-overlay.hidden {
    display: none;
  }

  .overlay-msg {
    font-size: 0.625rem;
    font-weight: 900;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-muted);
    margin: 0;
  }

  .field-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
  }

  .field-label {
    font-size: 0.625rem;
    font-weight: 900;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-muted);
  }

  .field-input-wrap {
    position: relative;
  }

  .field-input {
    width: 100%;
    background: var(--bg-page);
    border: 2px solid var(--border-color);
    border-radius: 1rem;
    padding: 0.75rem 3rem 0.75rem 1rem;
    font-size: 1.5rem;
    font-weight: 900;
    color: var(--text-main);
    outline: none;
    transition: border-color 0.2s;
    box-sizing: border-box;
  }

  .field-input:focus {
    border-color: #6366f1;
  }

  .field-unit {
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
    font-weight: 700;
  }

  .wof-results {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    transition: opacity 0.5s, filter 0.5s;
  }

  .wof-results.dimmed {
    opacity: 0.4;
    filter: grayscale(1);
    pointer-events: none;
  }

  .result-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem;
    border-radius: 1rem;
    border: 1px solid transparent;
    transition: opacity 0.3s;
  }

  .result-row.na {
    opacity: 0.3;
  }

  .result-row-indigo {
    background: rgba(99, 102, 241, 0.05);
    border-color: rgba(99, 102, 241, 0.15);
  }

  .result-row-amber {
    background: rgba(245, 158, 11, 0.05);
    border-color: rgba(245, 158, 11, 0.15);
  }

  .result-row-slate {
    background: var(--bg-page);
    border-color: var(--border-color);
  }

  .result-row-left {
    display: flex;
    align-items: center;
    gap: 0.75rem;
  }

  .result-icon {
    width: 1.25rem;
    height: 1.25rem;
  }

  .result-row-indigo .result-icon {
    color: #6366f1;
  }

  .result-row-amber .result-icon {
    color: #f59e0b;
  }

  .result-row-slate .result-icon {
    color: var(--text-muted);
  }

  .result-label {
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--text-main);
  }

  .result-val {
    font-size: 1.25rem;
    font-weight: 900;
  }

  .result-val-indigo {
    color: #6366f1;
  }

  .result-val-amber {
    color: #f59e0b;
  }

  .result-val-slate {
    color: var(--text-muted);
  }

  .ramp-body {
    position: relative;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .ramp-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    text-align: center;
    padding: 2rem;
    transition: opacity 0.5s;
  }

  .ramp-empty.hidden {
    display: none;
  }

  .ramp-empty-icon {
    width: 4rem;
    height: 4rem;
    border-radius: 1.5rem;
    background: var(--bg-page);
    border: 2px dashed var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
  }

  .ramp-empty-icon svg {
    width: 2rem;
    height: 2rem;
  }

  .ramp-empty-title {
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--text-muted);
    margin: 0;
  }

  .ramp-empty-desc {
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-muted);
    opacity: 0.6;
    margin: 0;
  }

  .ramp-active {
    width: 100%;
    animation: fade-in 0.7s ease;
  }

  .ramp-active.hidden {
    display: none;
  }

  .ramp-chart-wrap {
    width: 100%;
    aspect-ratio: 2 / 1;
    background: var(--bg-page);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 1rem;
    overflow: hidden;
  }

  .ramp-svg {
    width: 100%;
    height: 100%;
    overflow: visible;
  }

  .ramp-labels {
    font-size: 7px;
    font-weight: 900;
    fill: var(--text-muted);
    text-transform: uppercase;
  }

  .ramp-grid {
    color: var(--border-color);
    stroke-width: 0.5;
  }

  .ramp-fill-path {
    transition: all 1s ease;
  }

  .ramp-line {
    color: #6366f1;
    transition: all 1s ease;
  }

  .ramp-time-labels {
    font-size: 7px;
    font-weight: 900;
    fill: var(--text-muted);
    text-transform: uppercase;
  }

  .ph-card {
    gap: 1.5rem;
  }

  .ph-header-text {
    display: flex;
    flex-direction: column;
    gap: 0.125rem;
  }

  .ph-subtitle {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin: 0;
  }

  .ph-body {
    position: relative;
  }

  .ph-grid {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 1.5rem;
    align-items: start;
  }

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

  .ph-slider {
    width: 100%;
    height: 0.5rem;
    border-radius: 9999px;
    background: var(--border-color);
    appearance: none;
    cursor: pointer;
    accent-color: #8b5cf6;
  }

  .ph-range-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.625rem;
    font-weight: 700;
    color: var(--text-muted);
    padding: 0 0.25rem;
  }

  .ph-result {
    background: var(--bg-page);
    border: 2px dashed var(--border-color);
    border-radius: 1rem;
    padding: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 4rem;
  }

  .ph-result span {
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--text-main);
    text-align: center;
  }

  input[type="number"]::-webkit-inner-spin-button,
  input[type="number"]::-webkit-outer-spin-button {
    -webkit-appearance: none;
    margin: 0;
  }

  @keyframes fade-in {
    from {
      opacity: 0;
    }
    to {
      opacity: 1;
    }
  }

  @keyframes slide-in {
    from {
      opacity: 0;
      transform: translateY(10px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }

  [data-fiber-btn] {
    animation: slide-in 0.3s ease-out forwards;
  }

  @media (max-width: 768px) {
    .profile-grid {
      grid-template-columns: 1fr;
    }

    .tool-grid {
      grid-template-columns: 1fr;
    }

    .ph-grid {
      grid-template-columns: 1fr;
    }
  }