/* =====================
       CSS VARIABLES
    ===================== */
    :root {
      --primary: #003580;
      --primary-hover: #002a66;
      --primary-light: rgba(0,53,128,0.08);
      --primary-ring: rgba(0,53,128,0.12);
      --primary-shadow: rgba(0,53,128,0.2);
      --bg-page: #f8fafc;
      --bg-white: #ffffff;
      --border: #e2e8f0;
      --border-light: #f1f5f9;
      --text-dark: #1e293b;
      --text-body: #64748b;
      --text-muted: #94a3b8;
      --success: #22c55e;
      --error: #ef4444;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.07);
      --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
      --shadow-primary: 0 6px 20px rgba(0,53,128,0.22);
      --radius-sm: 0.25rem;
      --radius-md: 0.5rem;
      --radius-lg: 0.75rem;
      --radius-xl: 1rem;
      --radius-full: 9999px;
      --font: 'Inter', sans-serif;
    }

    /* =====================
       RESET & BASE
    ===================== */
    *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: var(--font);
      background: var(--bg-page);
      color: var(--text-dark);
      min-height: 100vh;
      line-height: 1.5;
    }
    a { color: inherit; text-decoration: none; }
    ul { list-style: none; }
    input, select, button, textarea { font-family: inherit; }
    img { display: block; width: 100%; height: 100%; object-fit: cover; }
    hr { border: none; border-top: 1px solid var(--border-light); }
    .material-symbols-outlined {
      font-variation-settings: 'FILL' 0, 'wght' 400, 'GRAD' 0, 'opsz' 24;
    }

    /* =====================
       FORM INPUT STATES
    ===================== */
    input:focus, textarea:focus {
      outline: none !important;
      border-color: var(--primary) !important;
      box-shadow: 0 0 0 4px var(--primary-ring) !important;
    }
    input:not(:placeholder-shown):invalid {
      border-color: var(--error) !important;
      background-color: rgba(239,68,68,0.05) !important;
    }
    input:not(:placeholder-shown):valid {
      border-color: var(--success) !important;
    }

    /* =====================
       CONTAINER
    ===================== */
    .container {
      max-width: 1240px;
      margin: 0 auto;
      padding: 0 1.5rem;
    }

    /* =====================
       HEADER
    ===================== */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: var(--bg-white);
      border-bottom: 1px solid var(--border);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 5rem;
    }
    .header-left { display: flex; align-items: center; gap: 3rem; }

    .logo { display: flex; align-items: center; gap: 0.5rem; color: var(--primary); }
    .logo .material-symbols-outlined { font-size: 1.875rem; }
    .logo-text {
      font-size: 1.25rem;
      font-weight: 700;
      letter-spacing: -0.01em;
      color: var(--text-dark);
      text-transform: uppercase;
    }

    .main-nav { display: none; align-items: center; gap: 2rem; }
    .main-nav a { font-size: 0.875rem; font-weight: 500; transition: color 0.2s; }
    .main-nav a:hover { color: var(--primary); }

    .header-right { display: flex; align-items: center; gap: 1.5rem; }
    .header-search-wrap {
      display: none;
      position: relative;
    }
    .header-search-wrap .material-symbols-outlined {
      position: absolute;
      left: 0.75rem;
      top: 50%;
      transform: translateY(-50%);
      color: var(--text-muted);
      font-size: 1.25rem;
      pointer-events: none;
    }
    .header-search-wrap input {
      padding: 0.5rem 1rem 0.5rem 2.5rem;
      background: #f8fafc;
      border: 1px solid var(--border);
      border-radius: var(--radius-lg);
      font-size: 0.875rem;
      width: 16rem;
      color: var(--text-dark);
      transition: all 0.2s;
    }
    .header-search-wrap input::placeholder { color: var(--text-muted); }

    .header-avatar {
      width: 2.5rem;
      height: 2.5rem;
      border-radius: var(--radius-full);
      background: #e2e8f0;
      border: 1px solid #cbd5e1;
      overflow: hidden;
      flex-shrink: 0;
    }

    /* =====================
       MAIN
    ===================== */
    .main-content { padding: 2rem 0; }

    /* =====================
       CHECKOUT PROGRESS
    ===================== */
    .checkout-progress { margin-bottom: 2.5rem; }
    .progress-top {
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 1rem;
    }
    .checkout-title { font-size: 1.5rem; font-weight: 700; }
    .progress-step-count { font-size: 0.875rem; color: var(--text-muted); }

    .progress-bars {
      display: flex;
      align-items: center;
      gap: 1rem;
    }
    .progress-bar {
      flex: 1;
      height: 0.5rem;
      border-radius: var(--radius-full);
      background: #e2e8f0;
    }
    .progress-bar.active { background: var(--primary); }

    .progress-labels {
      display: flex;
      justify-content: space-between;
      margin-top: 0.75rem;
    }
    .progress-label {
      font-size: 0.75rem;
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 0.07em;
      color: var(--text-muted);
    }
    .progress-label.active { color: var(--primary); }

    /* =====================
       PAGE LAYOUT
    ===================== */
    .page-layout {
      display: grid;
      grid-template-columns: 1fr;
      gap: 2.5rem;
      align-items: start;
    }

    /* =====================
       FORM SECTIONS
    ===================== */
    .form-sections { display: flex; flex-direction: column; gap: 2rem; }

    .form-card {
      background: var(--bg-white);
      padding: 2rem;
      border-radius: var(--radius-xl);
      border: 1px solid var(--border);
      box-shadow: var(--shadow-sm);
    }
    .form-card-header {
      display: flex;
      align-items: center;
      gap: 0.75rem;
      margin-bottom: 1.5rem;
    }
    .form-card-header .material-symbols-outlined { color: var(--primary); }
    .form-card-header h3 { font-size: 1.25rem; font-weight: 700; }

    .form-grid {
      display: grid;
      grid-template-columns: 1fr;
      gap: 1.5rem;
    }
    .form-group { display: flex; flex-direction: column; gap: 0.5rem; }
    .form-group label {
      font-size: 0.875rem;
      font-weight: 500;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .form-group label .material-symbols-outlined { font-size: 0.75rem; }
    .form-group label.muted { color: var(--text-muted); font-weight: 400; }

    .form-input {
      width: 100%;
      background: var(--bg-white);
      border: 1px solid var(--border);
      border-radius: var(--radius-lg);
      padding: 0.75rem;
      font-size: 0.875rem;
      color: var(--text-dark);
      transition: border-color 0.2s, box-shadow 0.2s, background 0.2s;
    }
    .form-input::placeholder { color: var(--text-muted); }

    .form-textarea {
      width: 100%;
      background: var(--bg-white);
      border: 1px solid var(--border);
      border-radius: var(--radius-lg);
      padding: 0.75rem;
      font-size: 0.875rem;
      color: var(--text-dark);
      resize: vertical;
      transition: border-color 0.2s, box-shadow 0.2s;
    }
    .form-textarea::placeholder { color: var(--text-muted); }
    .form-textarea:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 0 4px var(--primary-ring);
    }

    .col-span-2 { grid-column: span 2; }

    /* =====================
       SIDEBAR
    ===================== */
    .sidebar-sticky { position: sticky; top: 7rem; display: flex; flex-direction: column; gap: 1.5rem; }

    /* Order Summary Card */
    .order-card {
      background: var(--bg-white);
      border: 1px solid var(--border);
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .order-card-image {
      height: 12rem;
      width: 100%;
      position: relative;
    }
    .order-card-image img { width: 100%; height: 100%; }
    .order-card-image-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(to top, rgba(0,0,0,0.6), transparent);
      display: flex;
      align-items: flex-end;
      padding: 1.5rem;
    }
    .order-card-image-overlay h4 { color: white; font-weight: 700; font-size: 1.125rem; }

    .order-card-body { padding: 1.5rem; display: flex; flex-direction: column; gap: 1.5rem; }

    .order-details { display: flex; flex-direction: column; gap: 0.75rem; }
    .order-detail-row {
      display: flex;
      justify-content: space-between;
      font-size: 0.875rem;
    }
    .order-detail-row span:first-child { color: var(--text-muted); }
    .order-detail-row span:last-child { font-weight: 500; }

    .order-pricing { display: flex; flex-direction: column; gap: 0.75rem; }
    .pricing-row {
      display: flex;
      justify-content: space-between;
      font-size: 0.875rem;
    }
    .pricing-row span:first-child { color: var(--text-muted); }
    .pricing-row.discount span { color: var(--primary); font-weight: 700; }

    .order-total {
      display: flex;
      justify-content: space-between;
      align-items: flex-end;
    }
    .total-label {
      font-size: 0.75rem;
      color: var(--text-muted);
      text-transform: uppercase;
      font-weight: 600;
      letter-spacing: 0.07em;
      margin-bottom: 0.25rem;
    }
    .total-amount { font-size: 1.875rem; font-weight: 700; }
    .total-note { font-size: 0.625rem; color: var(--text-muted); }

    .btn-continue {
      width: 100%;
      background: var(--primary);
      color: white;
      border: none;
      padding: 1rem;
      border-radius: var(--radius-lg);
      font-size: 1rem;
      font-weight: 700;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
      box-shadow: var(--shadow-primary);
      transition: background 0.2s, transform 0.1s;
    }
    .btn-continue:hover { background: var(--primary-hover); }
    .btn-continue:active { transform: scale(0.98); }
    .btn-continue .material-symbols-outlined { font-size: 1.25rem; transition: transform 0.2s; }
    .btn-continue:hover .material-symbols-outlined { transform: translateX(3px); }

    .order-note { text-align: center; font-size: 0.6875rem; color: var(--text-muted); }

    /* Security Badge */
    .security-badge {
      background: #f8fafc;
      border: 1px solid var(--border);
      border-radius: var(--radius-lg);
      padding: 1rem;
      display: flex;
      align-items: center;
      gap: 1rem;
    }
    .security-badge .material-symbols-outlined { color: var(--primary); font-size: 1.875rem; flex-shrink: 0; }
    .security-badge-text p:first-child {
      font-size: 0.75rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.07em;
      margin-bottom: 0.2rem;
    }
    .security-badge-text p:last-child { font-size: 0.6875rem; color: var(--text-muted); }

    /* =====================
       FOOTER
    ===================== */
    .site-footer {
      background: var(--bg-white);
      border-top: 1px solid var(--border);
      margin-top: 5rem;
      padding: 3rem 0 2rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 1fr;
      gap: 3rem;
      margin-bottom: 3rem;
    }
    .footer-brand { display: flex; flex-direction: column; gap: 1.5rem; }
    .footer-brand-logo { display: flex; align-items: center; gap: 0.5rem; color: var(--primary); }
    .footer-brand-logo .material-symbols-outlined { font-size: 1.5rem; }
    .footer-brand-logo span.brand-name {
      font-size: 1.125rem;
      font-weight: 700;
      color: var(--text-dark);
      text-transform: uppercase;
      letter-spacing: -0.01em;
    }
    .footer-brand p { font-size: 0.875rem; color: var(--text-muted); line-height: 1.7; }

    .footer-col h5 { font-weight: 700; margin-bottom: 1.5rem; }
    .footer-col ul { display: flex; flex-direction: column; gap: 1rem; }
    .footer-col ul li a { font-size: 0.875rem; color: var(--text-muted); transition: color 0.2s; }
    .footer-col ul li a:hover { color: var(--primary); }

    .footer-social { display: flex; gap: 1rem; }
    .footer-social a {
      width: 2.5rem;
      height: 2.5rem;
      border-radius: var(--radius-full);
      background: #f1f5f9;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: all 0.2s;
      color: var(--text-dark);
    }
    .footer-social a:hover { background: var(--primary); color: white; }
    .footer-social .material-symbols-outlined { font-size: 1.125rem; }

    .footer-bottom {
      padding-top: 2rem;
      border-top: 1px solid var(--border-light);
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 1rem;
    }
    .footer-bottom p { font-size: 0.75rem; color: var(--text-muted); }
    .footer-legal { display: flex; gap: 2rem; }
    .footer-legal a { font-size: 0.75rem; color: var(--text-muted); transition: color 0.2s; }
    .footer-legal a:hover { color: var(--primary); }

    /* =====================
       RESPONSIVE
    ===================== */
    @media (min-width: 640px) {
      .header-search-wrap { display: block; }
      .form-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (min-width: 768px) {
      .main-nav { display: flex; }
      .footer-grid { grid-template-columns: repeat(2, 1fr); }
      .footer-bottom { flex-direction: row; justify-content: space-between; }
    }
    @media (min-width: 1024px) {
      .page-layout { grid-template-columns: 8fr 4fr; }
      .footer-grid { grid-template-columns: repeat(4, 1fr); }
    }