:root {
    --yellow: #F5C400;
    --yellow-dark: #D9A800;
    --black: #1A1A1A;
    --white: #FFFFFF;
    --gray-light: #F0F0F0;
    --gray-mid: #AAAAAA;
    --gray-text: #555555;
  }

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

  body {
    font-family: 'Titillium Web', Arial, sans-serif;
    background: #fff;
    color: var(--black);
  }

  /* ============ NAV ============ */
  .nav {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 56px;
    background: rgba(255,255,255,1);
    border-bottom: 1px solid #e0e0e0;
    box-shadow: 0 4px 24px rgba(0,0,0,0.08);
    transition: padding .35s ease, box-shadow .4s ease;
  }
  .nav.scrolled {
    padding: 10px 56px;
    box-shadow: 0 4px 24px rgba(0,0,0,0.13);
  }
  .nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
  }
  .nav-logo img {
    height: 38px;
    width: auto;
    transition: height .3s ease;
  }
  .nav.scrolled .nav-logo img { height: 30px; }
  .nav-links {
    display: flex;
    align-items: center;
    gap: 36px;
    list-style: none;
  }
  .nav-links a {
    color: var(--black);
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 1px;
    text-transform: uppercase;
    opacity: 0.72;
    transition: opacity .2s, color .2s;
    position: relative;
    padding-bottom: 4px;
  }
  .nav-links a:hover { opacity: 1; color: var(--yellow-dark); }
  .nav-links a.active { color: var(--yellow-dark); opacity: 1; }
  .nav-links a.active::after {
    content: "";
    position: absolute;
    left: 0; right: 0; bottom: -5px;
    height: 2px;
    background: var(--yellow-dark);
    border-radius: 2px;
  }
  .nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    z-index: 20;
  }
  .nav-toggle span {
    display: block;
    width: 24px; height: 2px;
    background: var(--black);
    margin: 5px 0;
    transition: .25s;
  }

  /* ============ PAGE HEADER ============ */
  .page-header {
    position: relative;
    padding: 160px 56px 70px;
    background: var(--black);
    color: #fff;
    overflow: hidden;
    text-align: center;
  }
  .page-header-bg {
    position: absolute; inset: 0;
    background: url('https://sedayu.com/wp-content/uploads/2021/10/construction.jpg') center / cover no-repeat;
    opacity: 0.18;
  }
  .page-header-bg::after {
    content: '';
    position: absolute; inset: 0;
    background: linear-gradient(160deg, rgba(10,10,10,0.7), rgba(5,5,5,0.5));
  }
  .page-header-inner {
    position: relative;
    z-index: 2;
    max-width: 760px;
    margin: 0 auto;
  }
  .page-header .eyebrow {
    display: inline-block;
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 2.5px;
    text-transform: uppercase;
    color: var(--yellow);
    margin-bottom: 14px;
    opacity: 0.9;
  }
  .page-header h1 {
    font-size: 48px;
    font-weight: 700;
    letter-spacing: -0.3px;
    margin-bottom: 18px;
    color: #fff;
  }
  .page-header p {
    font-size: 16px;
    line-height: 1.7;
    color: rgba(255,255,255,0.72);
  }

  /* ============ PROJECTS SECTION ============ */
  .projects-section {
    padding: 64px 56px 100px;
    background: #fff;
  }
  .projects-inner {
    max-width: 1280px;
    margin: 0 auto;
  }

  /* Filter tabs */
  .filter-tabs {
    display: flex;
    justify-content: center;
    gap: 36px;
    margin-bottom: 48px;
    border-bottom: 1px solid #e8e8e8;
    flex-wrap: wrap;
  }
  .filter-tab {
    background: none;
    border: none;
    padding: 0 0 14px;
    font-family: 'Titillium Web', Arial, sans-serif;
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 1.4px;
    text-transform: uppercase;
    color: var(--gray-mid);
    cursor: pointer;
    position: relative;
    transition: color .2s ease;
  }
  .filter-tab:hover { color: var(--black); }
  .filter-tab.active { color: var(--black); }
  .filter-tab.active::after {
    content: "";
    position: absolute;
    left: 0; right: 0; bottom: -1px;
    height: 2px;
    background: var(--yellow);
    border-radius: 2px;
  }

  /* Project grid */
  .projects-grid,
  #projectsGrid {
    display: flex !important;
    flex-wrap: wrap !important;
    gap: 24px !important;
    width: 100% !important;
  }
  .project-card {
    flex: 0 0 calc(25% - 18px) !important;
    max-width: calc(25% - 18px) !important;
    min-width: 200px !important;
    box-sizing: border-box !important;
  }
  @media (max-width: 1024px) {
    .project-card { flex: 0 0 calc(33.33% - 16px) !important; max-width: calc(33.33% - 16px) !important; }
  }
  @media (max-width: 768px) {
    .project-card { flex: 0 0 calc(50% - 8px) !important; max-width: calc(50% - 8px) !important; min-width: 0 !important; }
  }
  .project-card {
    text-decoration: none;
    color: inherit;
    display: block !important;
    transition: transform .25s ease;
  }
  .project-card:hover { transform: translateY(-4px); }
  .project-card.is-hidden { display: none !important; }

  .project-thumb {
    position: relative;
    width: 100%;
    padding-top: 66%;
    border-radius: 10px;
    overflow: hidden;
    background: #e8e8e8;
    margin-bottom: 14px;
  }
  .project-thumb img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform .4s ease;
  }
  .project-card:hover .project-thumb img { transform: scale(1.06); }

  .project-title {
    font-size: 14px;
    font-weight: 700;
    letter-spacing: 0.3px;
    text-align: center;
    color: var(--black);
    margin-bottom: 4px;
    line-height: 1.4;
  }
  .project-category {
    font-size: 11.5px;
    font-weight: 600;
    letter-spacing: 1.4px;
    text-transform: uppercase;
    text-align: center;
    color: var(--gray-mid);
  }

  .projects-empty {
    text-align: center;
    padding: 60px 0;
    color: var(--gray-mid);
    font-size: 15px;
    display: none;
  }

  /* ============ FOOTER ============ */
  .site-footer {
    background: #262626;
    color: #fff;
    padding: 72px 56px 0;
  }
  .footer-inner {
    max-width: 1280px; margin: 0 auto;
    display: grid; grid-template-columns: 1fr 1fr;
    gap: 64px; padding-bottom: 56px;
  }
  .footer-logo { margin-bottom: 18px; }
  .footer-logo img { height: 36px; width: auto; }
  .footer-tagline {
    font-size: 15px; line-height: 1.7;
    color: rgba(255,255,255,0.6);
    max-width: 360px; margin-bottom: 28px;
  }
  .footer-social { display: flex; gap: 12px; }
  .footer-social a {
    width: 38px; height: 38px; border-radius: 50%;
    border: 1px solid rgba(255,255,255,0.2);
    display: flex; align-items: center; justify-content: center;
    color: #fff; text-decoration: none; transition: all .2s;
  }
  .footer-social a:hover { background: var(--yellow); border-color: var(--yellow); color: var(--black); }
  .footer-social svg { width: 16px; height: 16px; }
  .footer-col-title {
    font-size: 12px; font-weight: 700; letter-spacing: 1.8px;
    text-transform: uppercase; color: rgba(255,255,255,0.45);
    margin-bottom: 20px;
  }
  .footer-office p {
    font-size: 15px; line-height: 1.7;
    color: rgba(255,255,255,0.75); margin-bottom: 20px;
  }
  .footer-office p strong { color: #fff; }
  .footer-contact-item {
    display: flex; align-items: center; gap: 12px;
    font-size: 15px; color: rgba(255,255,255,0.75);
    text-decoration: none; margin-bottom: 14px;
    transition: color .2s;
  }
  .footer-contact-item:hover { color: var(--yellow); }
  .footer-contact-item svg { width: 17px; height: 17px; flex-shrink: 0; stroke: var(--yellow); }
  .footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding: 24px 0; text-align: center;
    font-size: 13px; color: rgba(255,255,255,0.4);
    max-width: 1280px; margin: 0 auto;
  }
  .footer-bottom strong { color: rgba(255,255,255,0.75); }

  /* ============ SCROLL TOP ============ */
  .scroll-top-btn {
    position: fixed; right: 24px; bottom: 24px;
    width: 44px; height: 44px; border-radius: 50%;
    background: var(--yellow); border: none;
    display: flex; align-items: center; justify-content: center;
    cursor: pointer; z-index: 50;
    opacity: 0; pointer-events: none;
    transition: opacity .25s, transform .25s;
    box-shadow: 0 4px 16px rgba(245,196,0,0.4);
  }
  .scroll-top-btn.visible { opacity: 1; pointer-events: auto; }
  .scroll-top-btn:hover { transform: translateY(-2px); }
  .scroll-top-btn svg { width: 20px; height: 20px; stroke: var(--black); }

  /* ============ RESPONSIVE ============ */
  @media (max-width: 1024px) {
    .page-header { padding: 140px 40px 56px; }
    .page-header h1 { font-size: 38px; }
    .projects-section { padding: 48px 40px 80px; }
    .projects-grid { grid-template-columns: repeat(3, 1fr) !important; gap: 22px !important; }
  }
  @media (max-width: 768px) {
    .nav { padding: 14px 20px; }
    .nav-links {
      position: fixed; top: 0; right: 0; height: 100vh;
      width: 78%; max-width: 300px;
      background: #fff; flex-direction: column;
      align-items: flex-start; padding: 88px 28px; gap: 24px;
      transform: translateX(100%); transition: transform .3s; z-index: 15;
      box-shadow: -8px 0 40px rgba(0,0,0,0.18);
    }
    .nav-links.open { transform: translateX(0); }
    .nav-toggle { display: block; }
    .page-header { padding: 120px 20px 50px; }
    .page-header h1 { font-size: 30px; }
    .projects-section { padding: 40px 20px 64px; }
    .filter-tabs { gap: 20px; }
    .filter-tab { font-size: 12px; }
    .projects-grid { grid-template-columns: repeat(2, 1fr) !important; gap: 16px !important; }
    .project-title { font-size: 12.5px; }
    .site-footer { padding: 56px 20px 0; }
    .footer-inner { grid-template-columns: 1fr; gap: 36px; padding-bottom: 40px; }
  }
  @media (max-width: 480px) {
    .projects-grid { grid-template-columns: repeat(2, 1fr) !important; gap: 12px !important; }
  }
  

  #projectLightbox.open { display:flex !important; }
  #lbClose:hover { background:rgba(255,255,255,0.15) !important; }
  body.lb-open { overflow:hidden; }
  @media (max-width: 480px) {
    #lbInner { border-radius:12px; }
    #lbInner > div:last-child { padding:20px; }
    #lbName { font-size:18px !important; }
  }