:root {
      --content-width: 55%;
    }

    body {
      background: linear-gradient(145deg, #f8fdfb 0%, #edf7f3 100%);
      font-family: 'Segoe UI', Roboto, system-ui, sans-serif;
      min-height: 100vh;
      margin: 0;
      display: flex;
      flex-direction: column;
    }

    /* HEADER */
    .brand-header {
      text-align: center;
      color: white;
      background: linear-gradient(135deg, #25d366, #128c7e);
      border-radius: 0 0 50% 50% / 0 0 80px 80px;
      padding: 2rem 1rem 3rem 1rem;
      box-shadow: 0 12px 25px rgba(0, 0, 0, 0.2);
      max-width: var(--content-width);
      margin: 0 auto 2rem auto;
      width: 100%;
    }
    .brand-header img {
      max-width: 440px;
      width: 100%;
      height: auto;
      filter: drop-shadow(0 8px 16px rgba(0,0,0,0.3));
      transition: transform 0.3s;
      margin-bottom: 1rem;
    }
    .brand-header img:hover {
      transform: scale(1.02);
    }
    .brand-header .subtitle {
      font-size: 1.3rem;
      color: white;
      max-width: 600px;
      margin: 0 auto 1.5rem auto;
      font-style: italic;
      border-bottom: 2px solid rgba(255,255,255,0.5);
      display: inline-block;
      padding-bottom: 0.3rem;
      text-shadow: 1px 1px 3px rgba(0,0,0,0.2);
    }
    .button-group {
      display: flex;
      gap: 1rem;
      justify-content: center;
      flex-wrap: wrap;
    }
    .btn-shiny {
      background: rgba(255,255,255,0.25);
      backdrop-filter: blur(5px);
      border: 2px solid white;
      color: white;
      font-weight: 600;
      padding: 0.9rem 2rem;
      border-radius: 50px;
      box-shadow: 0 8px 18px rgba(0, 0, 0, 0.2);
      letter-spacing: 0.5px;
      position: relative;
      overflow: hidden;
      transition: all 0.3s ease;
      font-size: 1.1rem;
      min-width: 220px;
    }
    .btn-shiny::before {
      content: '';
      position: absolute;
      top: 0;
      left: -75%;
      width: 50%;
      height: 100%;
      background: linear-gradient(120deg, transparent, rgba(255,255,255,0.6), transparent);
      transform: skewX(-20deg);
      transition: left 0.6s ease;
    }
    .btn-shiny:hover::before {
      left: 125%;
    }
    .btn-shiny:hover {
      background: white;
      color: #128c7e;
      border-color: #128c7e;
      transform: translateY(-4px);
      box-shadow: 0 20px 30px rgba(0, 0, 0, 0.3);
    }

    /* CONTENT WRAPPER (timeline saja) */
    .content-wrapper {
      width: 100%;
      max-width: var(--content-width);
      margin: 0 auto 1rem auto;
      background-color: rgba(255,255,255,0.7);
      backdrop-filter: blur(4px);
      border-radius: 3rem 3rem 2rem 2rem;
      padding: 2rem 2rem 1.5rem;
      box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
      flex: 1;
    }

    /* Timeline container */
    .timeline-container {
      position: relative;
      padding: 1.8rem 0;
      margin-bottom: 2rem;
    }

    /* Garis tengah */
    .timeline-container::before {
      content: '';
      position: absolute;
      left: 50%;
      transform: translateX(-50%);
      width: 4px;
      height: 100%;
      background: linear-gradient(to bottom, #a0d6cc, #2a9d8f, #a0d6cc);
      border-radius: 10px;
      box-shadow: 0 0 12px rgba(0,0,0,0.1);
      z-index: 0;
    }

    .timeline-item {
      position: relative;
      z-index: 2;
      margin-bottom: 2.5rem;
      align-items: center;
    }

    /* Ikon lingkaran kosong */
    .timeline-item .timeline-icon {
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      width: 26px;
      height: 26px;
      background: white;
      border: 2px solid #128c7e;
      border-radius: 50%;
      box-shadow: 0 4px 10px rgba(0, 0, 0, 0.15);
      z-index: 10;
    }

    /* Card timeline */
    .card-timeline {
      background-color: white;
      border: none;
      border-radius: 28px;
      box-shadow: 0 18px 25px -8px rgba(0, 0, 0, 0.4);
      padding: 1.5rem 1.8rem;
      transition: transform 0.2s, box-shadow 0.2s;
      cursor: pointer;
      width: 95%;
      color: #000000;
      border-left: 6px solid #2a9d8f;
    }
    .card-timeline:hover {
      transform: scale(1.02) translateY(-4px);
      box-shadow: 0 25px 35px -8px rgba(0, 0, 0, 0.5);
    }

    /* Card kiri */
    .timeline-item .col-6:first-child .card-timeline {
      margin-left: 0;
      margin-right: -8px;
      width: 95%;
    }

    /* Card kanan */
    .timeline-item .col-6:last-child .card-timeline {
      margin-left: 15px;
      margin-right: 0;
      width: 95%;
    }

    .card-timeline h4 {
      font-weight: 700;
      margin-bottom: 0.75rem;
      color: #000000;
    }
    .card-timeline p {
      margin-bottom: 0.5rem;
      color: #222222;
    }
    .badge-version {
      background-color: #e0f2f0;
      color: #000000;
      padding: 0.3rem 1rem;
      border-radius: 30px;
      font-size: 0.85rem;
      font-weight: 600;
      display: inline-block;
      border: 1px solid #a8e6d7;
    }

    /* Tombol muat lainnya */
    .btn-muat {
      background: linear-gradient(145deg, #ffffff, #f0f7f4);
      border: 2px solid #2a9d8f;
      color: #000000;
      font-weight: 600;
      padding: 0.8rem 2.8rem;
      border-radius: 60px;
      box-shadow: 0 10px 18px rgba(0, 0, 0, 0.15);
      transition: 0.25s;
      letter-spacing: 0.5px;
    }
    .btn-muat:hover {
      background: #2a9d8f;
      color: white;
      border-color: white;
      box-shadow: 0 14px 24px rgba(0, 0, 0, 0.25);
    }

    /* Tombol kembali ke atas (fixed) */
    #backToTopBtn {
      position: fixed;
      bottom: 30px;
      right: 30px;
      width: 60px;
      height: 60px;
      border-radius: 50%;
      background: white;
      border: 3px solid #2a9d8f;
      color: #2a9d8f;
      font-size: 24px;
      box-shadow: 0 8px 18px rgba(0, 0, 0, 0.3);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: opacity 0.3s ease, visibility 0.3s ease;
      opacity: 0;
      visibility: hidden;
      z-index: 9999;
    }
    #backToTopBtn.show {
      opacity: 1;
      visibility: visible;
    }
    #backToTopBtn:hover {
      background: #2a9d8f;
      color: white;
      transform: scale(1.1);
      box-shadow: 0 12px 24px rgba(0, 0, 0, 0.4);
    }

    /* Footer terpisah */
    .footer-sederhana {
      background-color: rgba(255, 255, 255, 0.7);
      backdrop-filter: blur(5px);
      color: #000000;
      padding: 1.5rem 0;
      border-radius: 3rem 3rem 0 0;
      border-top: 2px solid rgba(42, 157, 143, 0.3);
      max-width: var(--content-width);
      margin: 1.5rem auto 0 auto;
      width: 100%;
    }
    .footer-sederhana .footer-links {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 1.5rem 2rem;
      padding: 0 1rem;
    }
    .footer-sederhana a {
      color: #000000;
      text-decoration: none;
      font-weight: 500;
      opacity: 0.8;
      transition: 0.2s;
      white-space: nowrap;
    }
    .footer-sederhana a:hover {
      opacity: 1;
      color: #000000;
    }

    /* ANIMASI FADE-IN UNTUK CARD */
    @keyframes fadeIn {
      0% { opacity: 0; transform: translateY(10px); }
      100% { opacity: 1; transform: translateY(0); }
    }
    .fade-in {
      animation: fadeIn 0.5s ease forwards;
    }

    /* Modal bounce */
    @keyframes bounce {
      0%,20%,50%,80%,100%{ transform:translateY(0); }
      40%{ transform:translateY(-30px); }
      60%{ transform:translateY(-15px); }
    }
    .modal.bounce .modal-dialog {
      animation: bounce 0.8s ease;
    }

    /* Responsif */
    @media (max-width: 768px) {
      :root { --content-width: 95% !important; }
      .brand-header img { max-width: 280px; }
      .timeline-container::before { display: none; }
      .timeline-item .timeline-icon { display: none; }
      .timeline-item .col-6 { width: 100%; margin-bottom: 1.2rem; }
      .card-timeline { 
        width: 100% !important; 
        margin-left: 0 !important; 
        margin-right: 0 !important; 
      }
      .button-group {
        flex-direction: column;
        align-items: center;
      }
      .footer-sederhana .footer-links {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
      }
      .footer-sederhana a {
        white-space: normal;
        font-size: 1.1rem;
        padding: 0.3rem 0;
      }
      #backToTopBtn {
        bottom: 20px;
        right: 20px;
        width: 50px;
        height: 50px;
        font-size: 20px;
      }
    }