:root {
    --gold: #E8A020;
    --gold-light: #F0BC5A;
    --gold-pale: #FDF5E6;
    --dark: #1A1A1A;
    --mid: #4A4A4A;
    --muted: #8A8A8A;
    --border: #E2D9C8;
    --surface: #FAFAF8;
    --white: #FFFFFF;
    --red: #C0392B;
    --green: #27AE60;
    --radius: 10px;
    --shadow: 0 2px 12px rgba(0,0,0,0.07);
  }

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

  body {
    font-family: 'DM Sans', sans-serif;
    background: var(--surface);
    color: var(--dark);
    min-height: 100vh;
    padding-bottom: 120px;
  }

  /* Header */
  .header {
    background: var(--dark);
    padding: 0 40px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 68px;
    position: sticky;
    top: 0;
    z-index: 100;
  }

  .logo {
    display: flex;
    align-items: center;
    gap: 12px;
  }

  .logo-icon {
    width: 36px;
    height: 36px;
  }

  .logo-text {
    font-family: 'DM Serif Display', serif;
    color: var(--white);
    font-size: 20px;
    letter-spacing: 0.02em;
  }

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

  .header-meta {
    display: flex;
    align-items: center;
    gap: 20px;
  }

  .contract-id {
    font-size: 12px;
    color: var(--muted);
    font-weight: 400;
    letter-spacing: 0.05em;
  }

  .progress-wrap {
    display: flex;
    gap: 6px;
    align-items: center;
  }

  .progress-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
    background: #3A3A3A;
    transition: background 0.3s;
  }

  .progress-dot.active { background: var(--gold); }
  .progress-dot.done { background: var(--gold-light); }

  /* Steps nav */
  .steps-nav {
    background: var(--white);
    border-bottom: 1px solid var(--border);
    padding: 0 40px;
    display: flex;
    gap: 0;
    overflow-x: auto;
  }

  .step-tab {
    padding: 14px 24px;
    font-size: 13px;
    font-weight: 500;
    color: var(--muted);
    border-bottom: 2px solid transparent;
    cursor: pointer;
    white-space: nowrap;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    gap: 8px;
  }

  .step-tab:hover { color: var(--dark); }
  .step-tab.active { color: var(--gold); border-bottom-color: var(--gold); }
  .step-tab.done { color: var(--dark); }

  .step-num {
    width: 20px; height: 20px;
    border-radius: 50%;
    background: var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 11px;
    font-weight: 600;
    color: var(--muted);
    transition: all 0.2s;
    flex-shrink: 0;
  }

  .step-tab.active .step-num { background: var(--gold); color: var(--white); }
  .step-tab.done .step-num { background: var(--green); color: var(--white); }

  /* Main layout */
  .main { max-width: 860px; margin: 0 auto; padding: 40px 24px; }

  /* Section cards */
  .card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: 14px;
    margin-bottom: 20px;
    overflow: hidden;
    box-shadow: var(--shadow);
  }

  .card-header {
    padding: 18px 28px;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--white);
  }

  .card-icon {
    width: 32px; height: 32px;
    background: var(--gold-pale);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 15px;
    flex-shrink: 0;
  }

  .card-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--dark);
  }

  .card-subtitle {
    font-size: 12px;
    color: var(--muted);
    margin-top: 1px;
  }

  .card-body { padding: 24px 28px; }

  /* Form fields */
  .field-grid {
    display: grid;
    gap: 16px;
  }

  .field-grid-2 { grid-template-columns: 1fr 1fr; }
  .field-grid-3 { grid-template-columns: 1fr 1fr 1fr; }
  .field-grid-4 { grid-template-columns: 1fr 1fr 1fr 1fr; }

  .field {
    display: flex;
    flex-direction: column;
    gap: 6px;
  }

  .field-label {
    font-size: 12px;
    font-weight: 500;
    color: var(--mid);
    letter-spacing: 0.03em;
    text-transform: uppercase;
  }

  .field-label.required::after {
    content: ' *';
    color: var(--red);
  }

  input[type="text"],
  input[type="email"],
  input[type="tel"],
  input[type="number"],
  input[type="date"],
  select,
  textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius);
    font-family: 'DM Sans', sans-serif;
    font-size: 14px;
    color: var(--dark);
    background: var(--white);
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
    -webkit-appearance: none;
  }

  input:focus, select:focus, textarea:focus {
    border-color: var(--gold);
    box-shadow: 0 0 0 3px rgba(196,154,60,0.12);
  }

  select {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%238A8A8A' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 36px;
    cursor: pointer;
  }

  textarea { resize: vertical; min-height: 80px; }

  /* Spec option chips */
  .chip-group {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
  }

  .chip {
    padding: 8px 16px;
    border: 1.5px solid var(--border);
    border-radius: 8px;
    font-size: 13px;
    font-weight: 500;
    color: var(--mid);
    cursor: pointer;
    transition: all 0.15s;
    user-select: none;
    background: var(--white);
  }

  .chip:hover { border-color: var(--gold-light); color: var(--dark); }

  .chip.selected {
    background: var(--gold-pale);
    border-color: var(--gold);
    color: var(--dark);
  }

  /* Window type grid */
  .window-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
  }

  .window-card {
    border: 1.5px solid var(--border);
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.15s;
    background: var(--white);
    overflow: hidden;
    display: flex;
    flex-direction: column;
  }

  .window-card:hover { border-color: var(--gold-light); }
  .window-card.selected { border-color: var(--gold); background: var(--gold-pale); }

  .window-card-inner {
    padding: 16px 14px 14px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    position: relative;
    flex: 1;
  }

  .window-card .check {
    position: absolute;
    top: 8px; right: 8px;
    width: 18px; height: 18px;
    border-radius: 50%;
    border: 1.5px solid var(--border);
    background: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.15s;
  }

  .window-card.selected .check {
    background: var(--gold);
    border-color: var(--gold);
  }

  .window-card.selected .check::after {
    content: '';
    width: 8px; height: 5px;
    border-left: 2px solid white;
    border-bottom: 2px solid white;
    transform: rotate(-45deg) translateY(-1px);
    display: block;
  }

  .window-diagram {
    width: 72px;
    height: 72px;
  }

  .window-name {
    font-size: 12px;
    font-weight: 600;
    color: var(--dark);
    text-align: center;
    line-height: 1.3;
  }

  /* Window qty controls */
  .window-qty {
    display: none;
    align-items: center;
    gap: 8px;
  }

  .window-card.selected .window-qty { display: flex; }

  .qty-btn {
    width: 24px; height: 24px;
    border-radius: 6px;
    border: 1.5px solid var(--gold);
    background: var(--white);
    color: var(--gold);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
    transition: all 0.15s;
  }

  .qty-btn:hover { background: var(--gold); color: var(--white); }

  .qty-display {
    font-size: 14px;
    font-weight: 600;
    color: var(--dark);
    min-width: 24px;
    text-align: center;
  }

  /* Window options sub-panel */
  .window-options {
    display: none;
    background: #F5EFE0;
    border-top: 1px solid var(--border);
    padding: 10px 12px;
    gap: 6px;
    flex-wrap: wrap;
    width: 100%;
    flex-direction: column;
  }

  .window-card.selected .window-options { display: flex; }

  .win-opt-row {
    display: flex;
    align-items: center;
    gap: 6px;
    flex-wrap: wrap;
  }

  .win-opt-label {
    font-size: 10px;
    font-weight: 600;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    min-width: 52px;
  }

  /* Patio door operation builder */
  .patio-op-builder {
    display: flex;
    gap: 6px;
    align-items: center;
    flex-wrap: wrap;
    margin-top: 2px;
  }

  .panel-op {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 3px;
  }

  .panel-op-label { font-size: 9px; color: var(--muted); font-weight: 500; }

  .panel-op select {
    font-size: 10px;
    padding: 3px 6px;
    border-radius: 5px;
    border: 1px solid var(--border);
    background: var(--white);
    color: var(--dark);
    width: 56px;
    cursor: pointer;
  }

  .mini-chip {
    padding: 4px 10px;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 11px;
    font-weight: 500;
    color: var(--mid);
    cursor: pointer;
    transition: all 0.15s;
    background: var(--white);
  }

  .mini-chip.selected { background: var(--gold); border-color: var(--gold); color: var(--white); }

  /* Toggle switch */
  .toggle-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
  }

  .toggle-row:last-child { border-bottom: none; }

  .toggle-label { font-size: 14px; color: var(--dark); }
  .toggle-sub { font-size: 12px; color: var(--muted); margin-top: 2px; }

  .toggle {
    position: relative;
    width: 44px; height: 24px;
    flex-shrink: 0;
  }

  .toggle input { opacity: 0; width: 0; height: 0; }

  .toggle-track {
    position: absolute;
    inset: 0;
    background: var(--border);
    border-radius: 12px;
    cursor: pointer;
    transition: background 0.2s;
  }

  .toggle input:checked + .toggle-track { background: var(--gold); }

  .toggle-track::after {
    content: '';
    position: absolute;
    left: 3px; top: 3px;
    width: 18px; height: 18px;
    border-radius: 50%;
    background: white;
    transition: transform 0.2s;
    box-shadow: 0 1px 4px rgba(0,0,0,0.15);
  }

  .toggle input:checked + .toggle-track::after { transform: translateX(20px); }

  /* Payment section */
  .payment-method-group {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin-bottom: 20px;
  }

  .payment-option {
    border: 1.5px solid var(--border);
    border-radius: 10px;
    padding: 14px;
    cursor: pointer;
    transition: all 0.15s;
    text-align: center;
  }

  .payment-option:hover { border-color: var(--gold-light); }
  .payment-option.selected { border-color: var(--gold); background: var(--gold-pale); }

  .payment-option .pay-icon { font-size: 22px; margin-bottom: 6px; }
  .payment-option .pay-label { font-size: 13px; font-weight: 600; color: var(--dark); }
  .payment-option .pay-sub { font-size: 11px; color: var(--muted); margin-top: 2px; }

  .finance-details { display: none; }
  .finance-details.visible { display: block; }

  .price-summary {
    background: var(--dark);
    border-radius: 12px;
    padding: 20px 24px;
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 20px;
  }

  .price-item .price-label {
    font-size: 11px;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 6px;
  }

  .price-item .price-value {
    font-size: 22px;
    font-weight: 600;
    color: var(--white);
    font-family: 'DM Serif Display', serif;
  }

  .price-item .price-value.gold { color: var(--gold-light); }

  /* Step panels */
  .step-panel { display: none; }
  .step-panel.active { display: block; }

  /* Summary panel */
  .summary-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

  .summary-block {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 16px 18px;
  }

  .summary-block-title {
    font-size: 11px;
    font-weight: 600;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 10px;
  }

  .summary-row {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    padding: 4px 0;
    border-bottom: 1px solid var(--border);
  }

  .summary-row:last-child { border-bottom: none; }
  .summary-key { font-size: 12px; color: var(--muted); }
  .summary-val { font-size: 13px; font-weight: 500; color: var(--dark); }

  .window-summary-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 0;
    border-bottom: 1px solid var(--border);
    font-size: 13px;
  }

  .window-summary-item:last-child { border-bottom: none; }

  .win-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 24px; height: 24px;
    background: var(--gold);
    color: var(--white);
    border-radius: 6px;
    font-size: 12px;
    font-weight: 700;
    flex-shrink: 0;
  }

  /* Signature area */
  .sig-box {
    border: 1.5px dashed var(--border);
    border-radius: 12px;
    padding: 32px;
    text-align: center;
    color: var(--muted);
    font-size: 14px;
    background: var(--surface);
    margin-top: 16px;
  }

  .sig-box p { margin-top: 8px; font-size: 12px; }

  /* Bottom bar */
  .bottom-bar {
    position: fixed;
    bottom: 0; left: 0; right: 0;
    background: var(--white);
    border-top: 1px solid var(--border);
    padding: 16px 40px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    z-index: 100;
    box-shadow: 0 -4px 20px rgba(0,0,0,0.06);
  }

  .bottom-left { display: flex; align-items: center; gap: 16px; }

  .step-label {
    font-size: 12px;
    color: var(--muted);
  }

  .step-label strong { color: var(--dark); }

  .btn {
    padding: 11px 24px;
    border-radius: 10px;
    font-family: 'DM Sans', sans-serif;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: all 0.15s;
    display: inline-flex;
    align-items: center;
    gap: 8px;
  }

  .btn-ghost {
    background: transparent;
    color: var(--mid);
    border: 1.5px solid var(--border);
  }

  .btn-ghost:hover { border-color: var(--mid); color: var(--dark); }

  .btn-primary {
    background: var(--gold);
    color: var(--white);
  }

  .btn-primary:hover { background: #B8892E; }

  .btn-submit {
    background: var(--dark);
    color: var(--white);
    padding: 13px 32px;
    font-size: 15px;
  }

  .btn-submit:hover { background: #2D2D2D; }

  .btn-arrow::after { content: '→'; }
  .btn-back::before { content: '←'; }

  /* Divider */
  .divider {
    height: 1px;
    background: var(--border);
    margin: 20px 0;
  }

  .section-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 14px;
  }

  /* Validation */
  .field-error {
    font-size: 11px;
    color: var(--red);
    margin-top: 2px;
    display: none;
  }

  .field.invalid input,
  .field.invalid select {
    border-color: var(--red);
  }

  .field.invalid .field-error { display: block; }

  /* Toast */
  .toast {
    position: fixed;
    bottom: 90px;
    left: 50%;
    transform: translateX(-50%) translateY(20px);
    background: var(--dark);
    color: var(--white);
    padding: 10px 20px;
    border-radius: 8px;
    font-size: 13px;
    opacity: 0;
    transition: all 0.3s;
    pointer-events: none;
    z-index: 200;
  }

  .toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

  @media (max-width: 640px) {
    .main { padding: 20px 16px; }
    .header { padding: 0 20px; }
    .steps-nav { padding: 0 16px; }
    .bottom-bar { padding: 14px 20px; }
    .field-grid-2, .field-grid-3, .field-grid-4 { grid-template-columns: 1fr; }
    .window-grid { grid-template-columns: repeat(2, 1fr); }
    .payment-method-group { grid-template-columns: 1fr; }
    .price-summary { grid-template-columns: 1fr; gap: 12px; }
    .summary-grid { grid-template-columns: 1fr; }
  }