:root {
      --bg: #0b1211;
      --ink: #0b1211;
      --ink-weak: #334155;
      --paper: #f8fafc;
      --brand: #0ea5a0;
      --brand-dark: #0f766e;
      --brand-light: #99f6e4;
      --accent: #14b8a6;
      --accent-ink: #0f766e;
      --ok: #2563eb;
      --warn: #b45309;
      --muted: #64748b;
      --ring: #99f6e4;
      --radius: 12px;
      --shadow: 0 10px 30px rgba(2,8,23,.15);
      --shadow-lg: 0 20px 50px rgba(2,8,23,.25);
      --max: 1100px;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: 'Noto Sans JP', system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #0f172a;
      background: #fff;
      line-height: 1.6;
      overflow-x: hidden;
    }

    /* Typography */
    h1, h2, h3 {
      line-height: 1.2;
      font-weight: 700;
    }

    /* Header */
    header {
      background: linear-gradient(135deg, #0f766e 0%, #0ea5a0 100%);
      color: #fff;
      position: relative;
      overflow: hidden;
    }

    header::before {
      content: '';
      position: absolute;
      top: -50%;
      right: -50%;
      width: 200%;
      height: 200%;
      background: radial-gradient(circle, rgba(255,255,255,0.05) 1px, transparent 1px);
      background-size: 50px 50px;
      transform: rotate(30deg);
      animation: drift 20s linear infinite;
    }

    @keyframes drift {
      0% { transform: rotate(30deg) translateX(0); }
      100% { transform: rotate(30deg) translateX(50px); }
    }

    .wrap {
      max-width: var(--max);
      margin: 0 auto;
      padding: 24px;
      position: relative;
      z-index: 1;
    }

    /* Navigation */
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 16px;
      animation: fadeInDown 0.6s ease-out;
    }

    .logo {
      font-weight: 800;
      letter-spacing: .02em;
      font-size: 20px;
      display: flex;
      align-items: center;
      gap: .5rem;
    }

    .logo-badge {
      display: inline-grid;
      place-items: center;
      width: 32px;
      height: 32px;
      border-radius: 8px;
      background: linear-gradient(135deg, #99f6e4, #5eead4);
      color: #0f766e;
      font-weight: 900;
      box-shadow: 0 4px 10px rgba(0,0,0,.1);
      transition: transform 0.3s ease;
    }

    .logo:hover .logo-badge {
      transform: rotate(10deg) scale(1.1);
    }

    .nav a.cta {
      display: inline-grid;
      place-items: center;
      width: 40px;
      height: 40px;
      padding: 0;
      background: rgba(11,19,32,0.9);
      color: #fff;
      border-radius: 999px;
      text-decoration: none;
      border: 1px solid rgba(255,255,255,.2);
      transition: all 0.3s ease;
    }

    .nav a.cta:hover {
      background: rgba(255,255,255,0.2);
      transform: translateY(-2px);
      box-shadow: 0 5px 15px rgba(0,0,0,.2);
    }

    .nav a.cta svg {
      width: 20px;
      height: 20px;
    }

    /* Hero */
    .hero {
      padding: 80px 24px 100px;
      animation: fadeIn 0.8s ease-out 0.2s both;
    }

    .hero h1 {
      font-size: clamp(32px, 5vw, 48px);
      margin: 0 0 16px;
      animation: slideInLeft 0.8s ease-out 0.4s both;
    }

    .hero p.lead {
      font-size: clamp(18px, 3vw, 22px);
      opacity: .95;
      margin: 0 0 24px;
      animation: slideInLeft 0.8s ease-out 0.6s both;
    }

    .chip {
      display: inline-block;
      background: rgba(255,255,255,.2);
      border: 1px solid rgba(255,255,255,.35);
      padding: 6px 12px;
      border-radius: 999px;
      font-size: 13px;
      margin-right: 8px;
      margin-bottom: 16px;
      backdrop-filter: blur(10px);
      animation: fadeIn 0.8s ease-out 0.3s both;
    }

    .cta-row {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      justify-content: center;
      align-items: center;
      margin-top: 32px;
      animation: fadeInUp 0.8s ease-out 0.8s both;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: .5rem;
      padding: 16px 24px;
      border-radius: 12px;
      text-decoration: none;
      font-weight: 700;
      border: 2px solid transparent;
      transition: all 0.3s ease;
      cursor: pointer;
      position: relative;
      overflow: hidden;
    }

    .btn::before {
      content: '';
      position: absolute;
      top: 50%;
      left: 50%;
      width: 0;
      height: 0;
      border-radius: 50%;
      background: rgba(255,255,255,.3);
      transform: translate(-50%, -50%);
      transition: width 0.6s, height 0.6s;
    }

    .btn:hover::before {
      width: 300px;
      height: 300px;
    }

    .btn.primary {
      background: #fff;
      color: #0f766e;
      box-shadow: 0 4px 15px rgba(0,0,0,.1);
    }

    .btn.primary:hover {
      transform: translateY(-3px);
      box-shadow: 0 8px 25px rgba(0,0,0,.2);
    }

    .btn.secondary {
      background: transparent;
      color: #fff;
      border-color: rgba(255,255,255,.5);
    }

    .btn.secondary:hover {
      background: rgba(255,255,255,.1);
      border-color: #fff;
      transform: translateY(-3px);
    }

    /* Sections */
    .section {
      padding: 80px 24px;
      animation: fadeIn 0.8s ease-out;
    }

    .section h2 {
      font-size: clamp(24px, 4vw, 32px);
      margin: 0 0 24px;
      position: relative;
      display: inline-block;
    }

    .section h2::after {
      content: '';
      position: absolute;
      bottom: -8px;
      left: 0;
      width: 60px;
      height: 4px;
      background: linear-gradient(90deg, var(--accent), var(--brand-light));
      border-radius: 2px;
    }

    /* Grid */
    .grid {
      display: grid;
      gap: 20px;
    }

    @media(min-width: 768px) {
      .grid.cols-2 { grid-template-columns: repeat(2, 1fr); }
      .grid.cols-3 { grid-template-columns: repeat(3, 1fr); }
    }

    /* Cards */
    .card {
      background: #fff;
      border: 1px solid #e2e8f0;
      border-radius: var(--radius);
      padding: 24px;
      transition: all 0.3s ease;
      position: relative;
      overflow: hidden;
    }

    .card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 4px;
      background: linear-gradient(90deg, var(--accent), var(--brand));
      transform: translateX(-100%);
      transition: transform 0.3s ease;
    }

    .card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
    }

    .card:hover::before {
      transform: translateX(0);
    }

    /* KPI Cards */
    .kpi {
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .kpi .label {
      color: var(--muted);
      font-size: 13px;
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .kpi .value {
      font-size: clamp(24px, 3.5vw, 30px);
      font-weight: 800;
      color: var(--accent-ink);
      background: linear-gradient(135deg, var(--accent-ink), var(--brand));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .kpi small {
      color: var(--muted);
      font-size: 12px;
    }

    /* Problem Section */
    .problem {
      background: linear-gradient(180deg, #f1f5f9, #e2e8f0);
      position: relative;
    }

    /* Lists */
    .list {
      padding-left: 1.5rem;
    }

    .list li {
      margin: 0.5rem 0;
      position: relative;
    }

    .list li::marker {
      color: var(--accent);
    }

    /* Pills */
    .sol .pill {
      display: inline-block;
      background: linear-gradient(135deg, #ecfeff, #cffafe);
      color: #0f766e;
      border: 1px solid #99f6e4;
      padding: 6px 12px;
      border-radius: 999px;
      font-size: 13px;
      margin: 4px 4px 4px 0;
      transition: all 0.3s ease;
    }

    .sol .pill:hover {
      transform: scale(1.05);
      box-shadow: 0 4px 10px rgba(14,165,160,.2);
    }

    /* FAQ Section */
    .faq {
      background: linear-gradient(180deg, #f8fafc 0%, #fff 100%);
    }

    .faq h2 {
      text-align: center;
      font-size: clamp(26px, 4vw, 34px);
      margin-bottom: 32px;
    }

    .faq-list {
      display: grid;
      gap: 16px;
    }

    .faq-item {
      background: #fff;
      border-radius: var(--radius);
      border: 1px solid rgba(15, 118, 110, 0.12);
      box-shadow: var(--shadow);
      transition: box-shadow 0.3s ease, transform 0.3s ease;
      overflow: hidden;
    }

    .faq-item summary {
      list-style: none;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 16px;
      padding: 20px 24px;
      font-weight: 600;
      font-size: 18px;
      color: var(--ink);
      outline: none;
    }

    .faq-item summary::-webkit-details-marker {
      display: none;
    }

    .faq-item summary::after {
      content: '+';
      font-size: 24px;
      color: var(--brand-dark);
      transition: transform 0.3s ease;
    }

    .faq-item[open] {
      box-shadow: var(--shadow-lg);
      transform: translateY(-2px);
    }

    .faq-item[open] summary::after {
      content: '−';
      transform: rotate(180deg);
    }

    .faq-item summary:focus-visible {
      box-shadow: 0 0 0 3px var(--ring);
    }

    .faq-item .answer {
      padding: 0 24px 24px;
      color: var(--ink-weak);
      font-size: 15px;
      line-height: 1.7;
    }

    .faq-item .answer p + p {
      margin-top: 12px;
    }

    @media (min-width: 768px) {
      .faq-list {
        grid-template-columns: repeat(2, minmax(0, 1fr));
      }

      .faq-item:nth-child(odd) {
        transform-origin: top left;
      }

      .faq-item:nth-child(even) {
        transform-origin: top right;
      }
    }

    /* Video carousel */
    .videos {
      background: #f8fafc;
    }

    .video-carousel {
      position: relative;
      border-radius: var(--radius);
      overflow: hidden;
      background: #000;
      box-shadow: var(--shadow);
    }

    .video-stage {
      position: relative;
      aspect-ratio: 16 / 9;
      width: 100%;
      min-height: 220px; /* fallback minimum height */
      background: #000;
    }

    /* 常時効かせる比率ボックス（ブラウザ差異対策） */
    .video-stage::before {
      content: '';
      display: block;
      padding-top: 56.25%; /* 16:9 */
    }

    .video-slide {
      position: absolute;
      inset: 0;
      opacity: 0;
      transition: opacity .4s ease;
      display: grid;
      place-items: center;
      padding: 0;
    }

    .video-slide.active {
      opacity: 1;
      z-index: 2;
    }

    .player-inner {
      width: 100%;
      height: 100%;
      max-height: 100%;
    }

    .carousel-btn {
      position: absolute;
      top: 50%;
      transform: translateY(-50%);
      background: rgba(255,255,255,.15);
      backdrop-filter: blur(6px);
      color: #fff;
      border: 1px solid rgba(255,255,255,.3);
      width: 44px;
      height: 44px;
      border-radius: 999px;
      cursor: pointer;
      display: grid;
      place-items: center;
      transition: background .3s ease, transform .2s ease;
      z-index: 3;
    }

    .carousel-btn:hover {
      background: rgba(255,255,255,.3);
      transform: translateY(-50%) scale(1.05);
    }

    .carousel-btn.prev { left: 12px; }
    .carousel-btn.next { right: 12px; }

    .dots {
      position: absolute;
      left: 0;
      right: 0;
      bottom: 12px;
      display: flex;
      gap: 8px;
      justify-content: center;
      z-index: 3;
    }

    .dot {
      width: 10px;
      height: 10px;
      border-radius: 999px;
      border: 1px solid rgba(255,255,255,.5);
      background: rgba(255,255,255,.3);
      cursor: pointer;
    }

    .dot.active { background: #fff; border-color: #fff; }

    .thumb-strip {
      display: flex;
      gap: 8px;
      overflow-x: auto;
      padding: 10px;
      background: #0b1211;
      border-top: 1px solid rgba(255,255,255,.1);
    }

    .thumb {
      border: 0;
      padding: 0;
      background: transparent;
      cursor: pointer;
      border-radius: 8px;
      overflow: hidden;
      opacity: .7;
      transition: opacity .2s ease, transform .2s ease;
    }

    .thumb:hover { opacity: 1; transform: translateY(-2px); }

    .thumb-inner {
      width: 160px;
      height: 90px;
      background: #000;
    }

    @media (max-width: 767px) {
      .carousel-btn { display: none; }
      .thumb-inner { width: 120px; height: 68px; }
    }

    /* aspect-ratio フォールバック */
    @supports not (aspect-ratio: 1 / 1) {
      .video-stage {
        height: 0;
        padding-bottom: 56.25%; /* 16:9 */
      }
      .video-slide { position: absolute; inset: 0; }
    }

    /* Form Section */
    .form {
      background: linear-gradient(180deg, #f8fafc, #f1f5f9);
    }

    form {
      display: grid;
      gap: 20px;
    }

    fieldset {
      border: none;
      padding: 0;
    }

    label {
      font-weight: 600;
      font-size: 14px;
      color: var(--ink);
      display: block;
      margin-bottom: 8px;
    }

    input, select, textarea {
      width: 100%;
      padding: 14px 16px;
      border: 2px solid #cbd5e1;
      border-radius: 10px;
      background: #fff;
      font-size: 16px;
      transition: all 0.3s ease;
      font-family: inherit;
    }

    input:focus, select:focus, textarea:focus {
      outline: none;
      border-color: var(--accent);
      box-shadow: 0 0 0 3px rgba(14,165,160,.1);
    }

    textarea {
      resize: vertical;
      min-height: 100px;
    }

    .radio-row {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .radio-row label {
      font-weight: 500;
      display: flex;
      align-items: center;
      cursor: pointer;
      transition: color 0.3s ease;
    }

    .radio-row label:hover {
      color: var(--accent-ink);
    }

    input[type="radio"], input[type="checkbox"] {
      width: auto;
      margin-right: 8px;
      accent-color: var(--accent);
    }

    .submit {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      align-items: center;
      margin-top: 8px;
    }

    .submit .btn {
      background: linear-gradient(135deg, var(--accent), var(--brand));
      color: #fff;
      border: none;
      font-size: 16px;
      padding: 16px 32px;
    }

    .submit .btn:hover {
      transform: translateY(-3px);
      box-shadow: 0 10px 30px rgba(14,165,160,.3);
    }

    #form-status {
      color: var(--accent-ink);
      font-weight: 600;
      animation: fadeIn 0.5s ease;
    }

    /* Footer */
    footer {
      border-top: 1px solid #e2e8f0;
      padding: 40px 24px;
      background: #f8fafc;
    }

    footer strong {
      display: block;
      margin-bottom: 16px;
      color: var(--ink);
    }

    footer ol {
      padding-left: 1.5rem;
    }

    footer ol li {
      margin: 12px 0;
      color: var(--muted);
    }

    footer a {
      color: var(--accent-ink);
      word-break: break-all;
      transition: color 0.3s ease;
    }

    footer a:hover {
      color: var(--brand);
    }

    /* Utilities */
    .note {
      font-size: 13px;
      color: #64748b;
      margin-top: 8px;
    }

    .tiny {
      font-size: 12px;
      color: #64748b;
    }

    .foot {
      margin-top: 16px;
    }

    .sr-only {
      position: absolute !important;
      width: 1px;
      height: 1px;
      padding: 0;
      margin: -1px;
      overflow: hidden;
      clip: rect(0, 0, 0, 0);
      white-space: nowrap;
      border: 0;
    }

    /* Animations */
    @keyframes fadeIn {
      from {
        opacity: 0;
      }
      to {
        opacity: 1;
      }
    }

    @keyframes fadeInUp {
      from {
        opacity: 0;
        transform: translateY(30px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    @keyframes fadeInDown {
      from {
        opacity: 0;
        transform: translateY(-30px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    @keyframes slideInLeft {
      from {
        opacity: 0;
        transform: translateX(-30px);
      }
      to {
        opacity: 1;
        transform: translateX(0);
      }
    }

    /* Scroll animations */
    .fade-in-scroll {
      opacity: 0;
      transform: translateY(30px);
      transition: all 0.6s ease;
    }

    .fade-in-scroll.visible {
      opacity: 1;
      transform: translateY(0);
    }

    /* Mobile optimizations */
    @media (max-width: 767px) {
      .hero {
        padding: 60px 20px 80px;
      }

      .section {
        padding: 60px 20px;
      }

      .cta-row {
        flex-direction: column;
        align-items: center;
      }

      .btn {
        width: 100%;
      }

      .grid {
        gap: 16px;
      }

      .radio-row {
        flex-direction: column;
      }
    }

    /* Smooth scroll for Safari */
    @media screen and (prefers-reduced-motion: reduce) {
      * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
      }

      html {
        scroll-behavior: auto;
      }
    }

    /* Loading state */
    .loading {
      pointer-events: none;
      opacity: 0.6;
    }

    /* Success message animation */
    @keyframes slideInRight {
      from {
        opacity: 0;
        transform: translateX(30px);
      }
      to {
        opacity: 1;
        transform: translateX(0);
      }
    }

    .success-message {
      animation: slideInRight 0.5s ease;
      color: #059669;
      font-weight: 600;
    }

    /* Trust indicators */
    .trust-badges {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
      margin-top: 40px;
      padding-top: 40px;
      border-top: 1px solid rgba(255,255,255,.2);
    }

    .trust-badge {
      display: flex;
      align-items: center;
      gap: 8px;
      padding: 8px 16px;
      background: rgba(255,255,255,.1);
      border-radius: 999px;
      font-size: 14px;
      backdrop-filter: blur(10px);
    }

    .trust-badge svg {
      width: 20px;
      height: 20px;
    }

    /* CTA banner */
    .cta-banner {
      background: linear-gradient(135deg, var(--accent), var(--brand));
      color: white;
      padding: 60px 24px;
      text-align: center;
      position: relative;
      overflow: hidden;
    }

    .cta-banner::before {
      content: '';
      position: absolute;
      top: -50%;
      left: -50%;
      width: 200%;
      height: 200%;
      background: radial-gradient(circle, rgba(255,255,255,0.1) 1px, transparent 1px);
      background-size: 30px 30px;
      animation: drift 15s linear infinite;
    }

    .cta-banner h2 {
      font-size: clamp(28px, 4vw, 36px);
      margin-bottom: 16px;
    }

    .cta-banner p {
      font-size: 18px;
      margin-bottom: 32px;
      opacity: 0.95;
    }

    /* Footer links */
    .footer-links {
      text-align: center;
      margin: 24px 0;
    }

    .footer-links a {
      color: var(--brand-dark);
      text-decoration: none;
      margin: 0 8px;
      font-size: 14px;
    }

    .footer-links a:hover {
      text-decoration: underline;
    }