:root {
      --blue: #0647a8;
      --blue-dark: #042b66;
      --blue-soft: #eaf3ff;
      --yellow: #f3b51b;
      --text: #101828;
      --muted: #667085;
      --white: #ffffff;
    }

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

    body {
      font-family: "Inter", sans-serif;
      color: var(--text);
      background: var(--white);
    }

    .topbar {
      height: 104px;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
      border-top: 2px solid var(--blue-dark);
      background: var(--white);
    }

    .menu {
      position: absolute;
      left: 24px;
      font-size: 26px;
      color: var(--blue-dark);
      cursor: pointer;
    }

    .brand {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
      color: inherit;
    }

    .brand-logo {
      width: 72px;
      height: 72px;
      object-fit: cover;
      border-radius: 50%;
    }

    .brand-avatar {
      width: 82px;
      height: 109px;
      object-fit: cover;
      border-radius: 90%;
    }

    .brand-text {
      display: flex;
      flex-direction: column;
      line-height: 1;
    }

    .brand-text strong {
      font-size: 34px;
      font-weight: 800;
      color: var(--blue);
      letter-spacing: -1px;
      text-transform: lowercase;
    }

    .brand-text span {
      margin-top: 6px;
      font-size: 15px;
      color: var(--yellow);
      letter-spacing: 5px;
      font-weight: 700;
      text-transform: uppercase;
    }

    .search {
      position: absolute;
      right: 16px;
      width: 220px;
      height: 42px;
      border: 1.5px solid var(--blue-dark);
      border-radius: 24px;
      display: flex;
      align-items: center;
      padding: 0 14px;
      gap: 8px;
      background: var(--white);
    }

    .search input {
      border: 0;
      outline: 0;
      width: 100%;
      font-size: 15px;
      font-family: inherit;
    }

    .search i {
      color: var(--yellow);
      font-size: 19px;
    }

    .nav {
      height: 48px;
      background: linear-gradient(90deg, var(--blue-dark), var(--blue));
      display: flex;
      align-items: center;
      gap: 80px;
      padding: 0 32px;
    }

    .nav a {
      color: var(--white);
      text-decoration: none;
      font-size: 18px;
      font-weight: 800;
      text-transform: uppercase;
    }

    .nav a.active {
      color: var(--yellow);
      border-bottom: 3px solid var(--yellow);
      padding-bottom: 4px;
    }

    main {
      max-width: 1180px;
      padding: 34px 24px;
    }

    h1 {
      font-size: 34px;
      margin-bottom: 32px;
      color: var(--blue-dark);
      font-weight: 800;
    }

    .author {
      display: flex;
      align-items: center;
      gap: 14px;
      margin-bottom: 28px;
    }

    .author img {
      width: 78px;
      height: 88px;
      object-fit: cover;
      border-radius: 50%;
    }

    .author strong {
      display: block;
      color: var(--blue);
      font-size: 33px;
      line-height: 1;
      font-weight: 800;
      text-transform: lowercase;
    }

    .author span {
      display: block;
      margin-top: 7px;
      color: var(--yellow);
      font-weight: 800;
      letter-spacing: 7px;
      text-transform: uppercase;
    }

    .post-detail h1 {
      max-width: 900px;
      color: #000;
      font-size: 38px;
      line-height: 1.28;
      font-weight: 800;
      margin-bottom: 14px;
    }

    .post-detail .subtitle {
      max-width: 900px;
      font-size: 23px;
      line-height: 1.35;
      margin-bottom: 12px;
    }

    .date {
      display: block;
      font-size: 14px;
      color: var(--muted);
      margin-bottom: 28px;
    }

    .hero-image {
      width: 100%;
      max-width: 890px;
      border: 3px solid var(--yellow);
      border-radius: 6px;
      overflow: hidden;
      margin-bottom: 28px;
      background: #fff;
    }

    .hero-image img {
      width: 100%;
      display: block;
    }

    .content {
      max-width: 880px;
      font-size: 21px;
      line-height: 1.55;
    }

    .content p {
      margin-bottom: 18px;
    }

    .back {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      margin-bottom: 24px;
      color: var(--blue-dark);
      text-decoration: none;
      font-weight: 800;
    }

    @media (max-width: 768px) {
      .topbar {
        height: 88px;
      }

      .menu {
        left: 16px;
        font-size: 22px;
      }

      .brand-logo {
        width: 48px;
        height: 48px;
      }

      .brand-avatar {
        width: 52px;
        height: 68px;
      }

      .brand-text strong {
        font-size: 22px;
      }

      .brand-text span {
        font-size: 11px;
        letter-spacing: 3px;
      }

      .nav {
        overflow-x: auto;
        gap: 28px;
        padding: 0 18px;
      }

      .nav a {
        font-size: 15px;
        white-space: nowrap;
      }

      main {
        padding: 28px 16px;
      }

      h1 {
        font-size: 28px;
      }

      main {
        padding: 30px 13px 50px;
      }

      .author img {
        width: 64px;
        height: 84px;
      }

      .author strong {
        font-size: 28px;
      }

      .post-detail h1 {
        font-size: 33px;
      }

      .post-detail .subtitle,
      .content {
        font-size: 21px;
      }

      .nav {
          display: none;
      }
    }