:root {
      --bigo-primary: #2563eb;
      --bigo-accent: #f97316;
      --bigo-dark: #0f172a;
      --bigo-muted: #6b7280;
      --bigo-card: #ffffff;
      --bigo-radius: 18px;
      --bigo-shadow: 0 22px 50px rgba(15, 23, 42, 0.16);
    }

    body {
      font-family: "Poppins", sans-serif;
      color: #111827;
      overflow-x: hidden;
    }

    /* Hero */
    #hero-tutorial {
      background: radial-gradient(circle at top left, #1d4ed8 0, #020617 60%, #000);
      padding: 130px 0 90px;
      color: #e5e7eb;
      position: relative;
      overflow: hidden;
    }

    #hero-tutorial h1 {
      font-size: 2.7rem;
      font-weight: 800;
      margin-bottom: 10px;
      text-shadow: 0 3px 25px rgba(0, 0, 0, 0.6);
    }

    #hero-tutorial h1 span {
      color: #facc15;
    }

    #hero-tutorial p {
      font-size: 1.02rem;
      color: #c7d2fe;
      max-width: 640px;
    }

    .hero-chip-row {
      margin-top: 18px;
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      font-size: 0.84rem;
    }

    .hero-chip {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      padding: 6px 12px;
      border-radius: 999px;
      background: rgba(15, 23, 42, 0.85);
      border: 1px solid rgba(148, 163, 184, 0.7);
      color: #e5e7eb;
    }

    .hero-chip i {
      color: var(--bigo-accent);
      font-size: 0.95rem;
    }

    /* Section titles */
    .section-title {
      text-align: center;
      margin-bottom: 35px;
    }

    .section-title h2 {
      font-size: 0.95rem;
      letter-spacing: 0.14em;
      color: var(--bigo-primary);
      text-transform: uppercase;
      margin-bottom: 6px;
    }

    .section-title h3 {
      font-size: 2rem;
      font-weight: 800;
      color: #0f172a;
    }

    .section-title h3 span {
      color: var(--bigo-primary);
    }

    .section-title p {
      font-size: 0.94rem;
      color: var(--bigo-muted);
      max-width: 620px;
      margin: 0 auto;
    }

    /* Base card with red line */
    .tutorial-card,
    .device-card,
    .tips-card {
      background: var(--bigo-card);
      border-radius: var(--bigo-radius);
      padding: 24px 24px 20px;
      box-shadow: var(--bigo-shadow);
      border: 1px solid rgba(226, 232, 240, 0.9);
      position: relative;
      overflow-wrap: anywhere;
      word-wrap: break-word;
    }

    .tutorial-card::before,
    .device-card::before,
    .tips-card::before {
      content: "";
      position: absolute;
      left: 0;
      top: 12px;
      bottom: 12px;
      width: 4px;
      border-radius: 999px;
      background: linear-gradient(180deg, #ef4444, #f97316);
    }

    .tutorial-card h3,
    .device-card h3,
    .tips-card h3 {
      font-size: 1.25rem;
      font-weight: 800;
      color: #0f172a;
      margin-bottom: 8px;
    }

    .tutorial-card p,
    .device-card p,
    .tips-card p {
      font-size: 0.94rem;
      color: var(--bigo-muted);
    }

    /* Step chips */
    .step-label {
      display: inline-block;
      background: #eff6ff;
      color: var(--bigo-primary);
      padding: 4px 12px;
      border-radius: 999px;
      font-size: 0.78rem;
      font-weight: 600;
      letter-spacing: 0.08em;
      text-transform: uppercase;
      margin-bottom: 6px;
    }

    .step-number {
      width: 30px;
      height: 30px;
      border-radius: 999px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background: #f97316;
      color: #fff;
      font-weight: 700;
      font-size: 0.9rem;
      margin-right: 8px;
    }

    /* Device icon */
    .device-icon {
      font-size: 2rem;
      color: var(--bigo-primary);
      margin-bottom: 10px;
    }

    /* FAQ */
    .faq-section {
      padding: 50px 0 50px;
      background: #ffffff;
    }

    .faq-item {
      background: #ffffff;
      border-radius: 14px;
      padding: 14px 16px 14px 20px;
      border: 1px solid rgba(226, 232, 240, 0.95);
      box-shadow: 0 10px 22px rgba(15, 23, 42, 0.08);
      position: relative;
      overflow-wrap: anywhere;
      margin-bottom: 12px;
    }

    .faq-item::before {
      content: "";
      position: absolute;
      left: 0;
      top: 10px;
      bottom: 10px;
      width: 3px;
      border-radius: 999px;
      background: linear-gradient(180deg, #ef4444, #f97316);
    }

    .faq-item h4 {
      font-size: 1rem;
      font-weight: 700;
      margin-bottom: 6px;
    }

    .faq-item p {
      font-size: 0.9rem;
      color: var(--bigo-muted);
      margin-bottom: 0;
    }

    /* CTA */
    .cta-box {
      background: linear-gradient(135deg, #2563eb, #1e40af);
      border-radius: 22px;
      padding: 42px 35px;
      text-align: center;
      color: #ffffff;
      box-shadow: var(--bigo-shadow);
      margin-top: 30px;
    }

    .cta-box h3 {
      font-size: 1.8rem;
      font-weight: 800;
      margin-bottom: 8px;
    }

    .cta-box p {
      font-size: 0.96rem;
      margin-bottom: 15px;
      opacity: 0.95;
    }

    .cta-box a {
      background: #f97316;
      padding: 10px 22px;
      border-radius: 999px;
      color: #ffffff;
      font-weight: 600;
      font-size: 0.95rem;
      text-decoration: none;
      display: inline-block;
    }

    @media (max-width: 575.98px) {
      #hero-tutorial h1 {
        font-size: 2.1rem;
      }
    }