:root{
      --bg0: #050912;
      --panel: rgba(8,14,28,.92);
      --panel2: rgba(7,12,24,.88);
      --card: rgba(10,18,35,.55);

      --border: rgba(255,255,255,.10);
      --border2: rgba(255,255,255,.14);

      --text: rgba(255,255,255,.88);
      --muted: rgba(255,255,255,.68);
      --muted2: rgba(255,255,255,.55);

      --accent: #d7b56d;

      --maxw: 1120px;
      --radius: 22px;

      --font: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Arial, "Noto Sans", "Liberation Sans", sans-serif;
    }

    *{ box-sizing:border-box; }
    body{
      margin:0;
      font-family: var(--font);
      line-height:1.55;
      color: var(--text);
      background:
        radial-gradient(1200px 800px at 50% 0%, rgba(50,90,180,.18), transparent 65%),
        radial-gradient(900px 700px at 10% 30%, rgba(120,70,170,.12), transparent 60%),
        radial-gradient(900px 700px at 90% 40%, rgba(30,140,190,.10), transparent 60%),
        var(--bg0);
    }

    /* Header / nav */
    .site-header{ position: sticky; top:0; z-index: 100; }
    .top-panel{
      max-width:1100px;
      margin:16px auto -26px;
      padding:12px 20px;
      display:flex;
      align-items:center;
      justify-content:space-between;
      gap:8px;
      background: radial-gradient(circle at top, rgba(251,191,36,.40) 0, transparent 60%);
      border-radius:999px;
      box-shadow:0 12px 25px rgba(0,0,0,.55);
    }
    .top-brand{ display:flex; align-items:center; gap:10px; }
    .brand-logo{
      width:58px; height:58px; border-radius:50%;
      display:flex; align-items:center; justify-content:center;
      background: radial-gradient(circle at 30% 20%, #ffdf9a 0%, #f2a93b 35%, #0a1b3b 100%);
      overflow:hidden;
    }
    .brand-logo img{
      width:48px; height:48px; border-radius:50%;
      object-fit:cover;
      border:2px solid rgba(255,219,140,.8);
    }
    .brand-text{
      line-height:1.1;
      letter-spacing:.08em;
      font-weight:800;
      color: var(--accent);
      text-transform:uppercase;
      font-size:.95rem;
    }
    .brand-text span{
      display:inline-block;
      margin-top:3px;
      font-weight:600;
      color: var(--muted);
      font-size:.78rem;
      text-transform:none;
      letter-spacing:.05em;
    }
    .nav{ display:flex; gap:6px; flex-wrap:wrap; justify-content:flex-end; margin-left:auto; }
    .nav a{
      border-radius:999px;
      padding:6px 14px;
      font-size:.78rem;
      letter-spacing:.12em;
      text-transform:uppercase;
      background: rgba(10,23,52,.95);
      color:#e7edfc;
      text-decoration:none;
      box-shadow:0 0 2px rgba(255,230,180,.3), 0 6px 14px rgba(0,0,0,.6);
    }
    .nav a:hover{ filter: brightness(1.06); }
    .nav a[aria-current="page"]{
      outline:2px solid rgba(255,193,77,.35);
      outline-offset:2px;
    }

    .wrap{
      max-width: var(--maxw);
      margin: 0 auto;
      padding: 26px 16px 48px;
    }
    .panel{
      background: linear-gradient(180deg, var(--panel), var(--panel2));
      border: 1px solid var(--border);
      border-radius: var(--radius);
      box-shadow: 0 24px 60px rgba(0,0,0,.55), inset 0 1px 0 rgba(255,255,255,.06);
      overflow:hidden;
    }

    /* Column headers */
    .colhead{
      display:grid;
      grid-template-columns: 1fr 1fr;
      border-bottom: 1px solid var(--border);
      background: rgba(255,255,255,.03);
    }
    .colhead > div{
      padding: 10px 14px;
      text-align:center;
      font-size: 12px;
      font-weight: 900;
      letter-spacing:.4px;
      color: rgba(255,255,255,.78);
      text-transform: uppercase;
    }
    .colhead > div:first-child{ border-right: 1px solid var(--border); }
    .colhead a{
      color: inherit;
      text-decoration:none;
      display:block;
    }
    .colhead a:hover,
    .colhead a:focus{ text-decoration: underline; }

  .lang-label{
  line-height:1.1;
  letter-spacing:.08em;
  font-weight:800;
  color:#fff;                 /* <-- white */
  text-transform:uppercase;
  font-size:.95rem;
  text-decoration:none;
  display:inline-block;
  position:relative;
  padding-bottom:6px;
}

    .lang-label:hover {
    color: #ffffff;
    opacity: 0.8;
}
    .mast-block .lang-label {
    color: #ffffff !important;
}

.lang-label{
  line-height:1.1;
  letter-spacing:.08em;
  font-weight:800;
  color:#fff;                 /* <-- white */
  text-transform:uppercase;
  font-size:.95rem;
  text-decoration:none;
  display:inline-block;
  position:relative;
  padding-bottom:6px;
}
.lang-label::after{
  content:"";
  position:absolute;
  left:0;
  bottom:0;
  height:2px;
  width:100%;
  background: rgba(212,175,55,.85);
  transform: scaleX(.35);
  transform-origin:left;
  opacity:.7;
  transition: transform 200ms ease, opacity 200ms ease;
}

.lang-label:hover::after,
.lang-label.is-active::after{
  transform: scaleX(1);
  opacity:1;
}
/* 1) Smooth scrolling */
html {
  scroll-behavior: smooth;
}

/* 2) Make anchor landing align nicely (if you have a sticky header, adjust this) */
.lang-label-wrap {
  scroll-margin-top: 110px; /* tweak: 80–140px depending on your header/top padding */
}

/* 3) Language label styling */
.mast-block .lang-label {
  color: #fff !important;
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 1px;
  display: inline-block;
  position: relative;
  padding-bottom: 6px;
}

/* 4) Subtle gold underline (brand accent) */
.mast-block .lang-label::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  height: 2px;
  width: 100%;
  background: rgba(218, 165, 32, 0.85); /* “goldenrod-ish” subtle */
  transform: scaleX(0.35);
  transform-origin: left;
  transition: transform 220ms ease, opacity 220ms ease;
  opacity: 0.75;
}

.mast-block .lang-label:hover::after {
  transform: scaleX(1);
  opacity: 1;
}

/* 5) Active state underline stronger */
.mast-block .lang-label.is-active::after {
  transform: scaleX(1);
  opacity: 1;
}
    /* Layout: 2 columns desktop; stacked mobile */
    .lang-grid{
      display:grid;
      grid-template-columns: 1fr 1fr;
      align-items:start;
    }
    .lang{
      padding: 14px 16px 18px;
      min-width:0;
    }
    .lang-en{ border-right: 1px solid var(--border); }

    /* Anchor jump alignment */
    #english, #tieng-viet{ scroll-margin-top: 120px; }

.lang-toggle {
  position: fixed;
  top: calc(var(--sticky-offset) - 24px); /* was: 18px */
  right: 18px;
  z-index: 9999;
  display: flex;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 999px;
  background: rgba(10, 14, 24, 0.55);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: 0 8px 30px rgba(0,0,0,0.35);
}

.lang-toggle__btn{
  color: rgba(255,255,255,.86);
  text-decoration:none;
  font-weight:750;
  font-size:13px;
  padding:8px 12px;
  border-radius:999px;
  border:1px solid rgba(255,255,255,.14);
  background: rgba(255,255,255,.04);
  transition: transform 160ms ease, background 160ms ease, border-color 160ms ease, color 160ms ease;
}

.lang-toggle__btn:hover{
  transform: translateY(-1px);
  color:#fff;
  background: rgba(255,255,255,.08);
}

.lang-toggle__btn.is-active{
  color:#fff;
  border-color: rgba(212,175,55,.75);
  background: rgba(212,175,55,.14);
}
    /* ---------- Header blocks INSIDE the columns ---------- */
    .mast-block{
      /* Shorter + cleaner than before */
      color: #d4af37;
      text-decoration: none;
      padding: 14px 14px 12px;
      border: 1px solid rgba(255,255,255,.09);
      border-radius: 18px;

      /* Softer gold glow (less harsh, more readable) */
      background:
        radial-gradient(circle at top, rgba(251,191,36,.28) 0, transparent 60%),
        rgba(255,255,255,.02);

      box-shadow:
        inset 0 1px 0 rgba(255,255,255,.05),
        0 18px 40px rgba(0,0,0,.35);

      text-align:center;
      margin-bottom: 14px;

      /* Baseline/height alignment so both columns line up nicely */
      min-height: 150px;
      display:flex;
      flex-direction:column;
      justify-content:center;
      gap: 4px;
    }

    .mast-kicker{
      margin:0;
      font-size: 12px;
      letter-spacing:.06em;
      text-transform:uppercase;
      color: rgba(255,255,255,.70);
      font-weight:800;
    }
    .mast-brand{
      margin:0;
      font-size: 16px;
      font-weight:900;
      color: var(--accent);
      letter-spacing:.04em;
      text-transform:uppercase;
    }
    .mast-title{
      margin:0;
      font-size: 18px;
      font-weight:950;
      color: var(--accent);
      letter-spacing:.2px;
      line-height:1.15;
      text-transform:uppercase;
    }
    .mast-subtitle{
      margin:0;
      font-size: 12px;
      font-weight:700;
      color: rgba(255,255,255,.62);
      letter-spacing:.04em;
      text-transform:uppercase;
    }
    .mast-loc{
      margin: 2px 0 0;
      font-size: 12px;
      color: var(--muted2);
      font-weight:650;
    }

/* Sticky offset used by anchors + floating toggle */
:root{ --sticky-offset: 110px; }

html{ scroll-behavior: smooth; }
.lang-label-wrap{ scroll-margin-top: calc(var(--sticky-offset) + 8px); }
#english, #tieng-viet{ scroll-margin-top: 120px; }

/* Floating toggle (single definitive definition) */
.lang-toggle{
  position: fixed;
  top: calc(var(--sticky-offset) + 10px);
  right: 18px;
  z-index: 9999;

  display:flex;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 999px;

  background: rgba(10, 14, 24, 0.55);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: 0 8px 30px rgba(0,0,0,0.35);

  opacity: 0;
  transform: translateY(-8px);
  pointer-events: none;
  transition: opacity 220ms ease, transform 220ms ease;
}
.lang-toggle.is-visible{
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.lang-toggle__btn{
  color: rgba(255,255,255,.86);
  text-decoration:none;
  font-weight:750;
  font-size:13px;
  padding:8px 12px;
  border-radius:999px;
  border:1px solid rgba(255,255,255,.14);
  background: rgba(255,255,255,.04);
  transition: transform 160ms ease, background 160ms ease, border-color 160ms ease, color 160ms ease;
}
.lang-toggle__btn:hover{
  transform: translateY(-1px);
  color:#fff;
  background: rgba(255,255,255,.08);
}
.lang-toggle__btn.is-active{
  color:#fff;
  border-color: rgba(212,175,55,.75);
  background: rgba(212,175,55,.14);
}

/* Mobile safety */
@media (max-width: 720px){
  .lang-toggle{
    right: 12px;
    left: 12px;
    width: auto;
    justify-content: center;
    gap: 8px;
    padding: 8px 10px;
    border-radius: 16px;
  }
  .lang-toggle__btn{
    flex: 1;
    text-align: center;
    padding: 10px 12px;
    font-size: 12px;
  }
}

/* Start hidden; JS will enable it when appropriate */
.lang-toggle{
  opacity: 0;
  transform: translateY(-8px);
  pointer-events: none;
  transition: opacity 220ms ease, transform 220ms ease;
}

/* Visible state */
.lang-toggle.is-visible{
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
/* Your .mast-block sets gold color globally; override label to WHITE */
.mast-block .lang-label{
  color:#fff !important;
  text-decoration:none !important;
  font-weight:800;
  letter-spacing:.08em;
  display:inline-block;
  position:relative;
  padding-bottom:6px;
}

/* Subtle gold underline */
.mast-block .lang-label::after{
  content:"";
  position:absolute;
  left:0;
  bottom:0;
  height:2px;
  width:100%;
  background: rgba(212,175,55,.85); /* matches your gold */
  transform: scaleX(.35);
  transform-origin:left;
  opacity:.7;
  transition: transform 200ms ease, opacity 200ms ease;
}

.mast-block .lang-label:hover::after{
  transform: scaleX(1);
  opacity:1;
}

/* Active language underline (strong) */
.mast-block .lang-label.is-active::after{
  transform: scaleX(1);
  opacity:1;
}
    /* Typography */
    .sec-title{
      margin: 0 0 10px;
      font-size: 13px;
      font-weight: 900;
      letter-spacing: .25px;
      color: var(--accent);
    }
    p{ margin: 0 0 10px; font-size: 13px; color: var(--text); }
    ul{ margin: 0 0 10px 18px; padding: 0; }
    li{ margin: 0 0 6px; font-size: 13px; color: var(--text); }

    .note{
      background: var(--card);
      border: 1px solid var(--border);
      border-radius: 14px;
      padding: 12px;
    }

    /* Footer */
    .footer{
      display:grid;
      grid-template-columns: 1fr 1fr;
      border-top: 1px solid var(--border);
      background: rgba(255,255,255,.02);
    }
    .footer > div{
      padding: 10px 14px;
      text-align:center;
      font-size: 11px;
      color: var(--muted2);
    }
    .footer > div:first-child{ border-right: 1px solid var(--border); }

    /* Responsive */
    @media (max-width: 860px){
      .top-panel{ margin: 12px 12px -22px; }

      .colhead{ grid-template-columns: 1fr; }
      .colhead > div:first-child{
        border-right:0;
        border-bottom: 1px solid var(--border);
      }

      .lang-grid{ grid-template-columns: 1fr; }
      .lang-en{
        border-right:0;
        border-bottom: 1px solid var(--border);
      }

      .mast-block{
        min-height: 0; /* let it size naturally on mobile */
      }

      .footer{ grid-template-columns: 1fr; }
      .footer > div:first-child{
        border-right:0;
        border-bottom: 1px solid var(--border);
      }
    }