/* =========================================================================
   home-flux.css — Trang chủ FLUX (bản chính) · 5 màn full-screen scroll.
   Port từ concept đã chốt: trường tối liên tục + dòng sáng mảnh + ống kính lật.
   Đã BỎ: knot chương, câu cầu nối, picker phương án (theo chốt của user).
   Nav: pill nổi kiểu switcher — LOGO MÀU (không invert).
   Prefix: hf- (host) · fxn- (nav) · giữ flux-/fxk-/fxd-/fx-ftr- từ concept.
   ========================================================================= */

/* ---------- Root + trường nền cố định ------------------------------------ */
.hf-root { position: relative; }
.hf-field { position: fixed; inset: 0; z-index: 0; pointer-events: none; overflow: hidden;
  background:
    radial-gradient(1200px 900px at 78% 8%, rgba(99,219,198,0.14), transparent 60%),
    radial-gradient(1100px 900px at 12% 96%, rgba(255,136,29,0.12), transparent 58%),
    radial-gradient(1400px 1200px at 50% 40%, rgba(88,40,168,0.5), transparent 72%),
    linear-gradient(180deg, #17082f 0%, #0c0422 60%, #08021a 100%); }
.hf-field .glow-a { position: absolute; width: 60vw; height: 60vw; border-radius: 50%; filter: blur(90px); opacity: 0.5;
  background: radial-gradient(circle, rgba(99,219,198,0.5), transparent 62%); top: -14vw; right: -10vw; }
.hf-field .glow-b { position: absolute; width: 54vw; height: 54vw; border-radius: 50%; filter: blur(90px); opacity: 0.42;
  background: radial-gradient(circle, rgba(255,136,29,0.42), transparent 62%); bottom: -16vw; left: -12vw; }
.hf-particles { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; }

/* ---------- Host cuộn snap ------------------------------------------------ */
.hf-host { height: 100dvh; overflow-y: auto; overflow-x: hidden; position: relative; z-index: 1;
  scroll-snap-type: y mandatory; scroll-behavior: smooth; scrollbar-width: none; }
.hf-host::-webkit-scrollbar { width: 0; height: 0; }
.hf-panel { position: relative; min-height: 100dvh; width: 100%; scroll-snap-align: start; scroll-snap-stop: always;
  display: flex; flex-direction: column; justify-content: flex-start; overflow: hidden; }
.hf-panel > .hf-wrap { margin-top: auto; margin-bottom: auto; }
.hf-wrap { width: 100%; max-width: 1280px; margin: 0 auto; padding: 104px clamp(24px, 6vw, 88px) 72px; position: relative; z-index: 5; }

/* ---------- Reveal -------------------------------------------------------- */
.hf-w { display: inline-block; opacity: 0; transform: translateY(0.5em); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.hf-w > span { white-space: pre; }
.hf-panel.is-active .hf-w { opacity: 1; transform: none; }
.hf-rise { opacity: 0; transform: translateY(30px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.hf-panel.is-active .hf-rise { opacity: 1; transform: none; }

/* ---------- Dots điều hướng ----------------------------------------------- */
.hf-dots { position: fixed; right: 22px; top: 50%; transform: translateY(-50%); z-index: 60; display: grid; gap: 16px; }
.hf-dots .dot { position: relative; width: 11px; height: 11px; padding: 0; border: 0; background: transparent; cursor: pointer; display: grid; place-items: center; }
.hf-dots .dot::after { content: ''; width: 9px; height: 9px; border-radius: 50%; background: rgba(255,255,255,0.28); transition: all var(--dur-ui) var(--ease); }
.hf-dots .dot.on::after { background: var(--itb-teal); box-shadow: 0 0 12px var(--itb-teal); transform: scale(1.25); }
.hf-dots .lb { position: absolute; right: 22px; top: 50%; transform: translateY(-50%) translateX(6px); font-size: 11.5px; font-weight: 700;
  letter-spacing: 0.08em; text-transform: uppercase; color: rgba(255,255,255,0.85); white-space: nowrap; opacity: 0; pointer-events: none;
  transition: opacity var(--dur-micro) var(--ease), transform var(--dur-micro) var(--ease); }
.hf-dots .dot:hover .lb, .hf-dots .dot.on .lb { opacity: 1; transform: translateY(-50%) translateX(0); }

/* ---------- Nhịp lõi ------------------------------------------------------- */
.hf-rhythm { display: inline-flex; align-items: center; gap: 12px; flex-wrap: wrap; font-size: 13px; font-weight: 700; color: rgba(255,255,255,0.9); }
.hf-rhythm .seg { display: inline-flex; align-items: center; gap: 8px; }
.hf-rhythm .bead { width: 9px; height: 9px; border-radius: 50%; flex: none; }
.hf-rhythm .arw { color: rgba(255,255,255,0.4); font-size: 14px; }
.hf-rhythm.sm { font-size: 11.5px; gap: 9px; color: rgba(255,255,255,0.7); letter-spacing: 0.02em; }
.hf-rhythm.sm .seg { gap: 6px; }
.hf-rhythm.sm .bead { width: 7px; height: 7px; }
.hf-rhythm.sm .arw { font-size: 12px; color: rgba(255,255,255,0.32); }

/* ---------- Nút ------------------------------------------------------------ */
.hf-btn { display: inline-flex; align-items: center; gap: 10px; cursor: pointer; font-family: inherit; font-size: 16px; font-weight: 700;
  border: 0; border-radius: var(--r-pill); padding: 15px 28px; background: var(--itb-orange); color: #2a1200;
  transition: transform var(--dur-micro) var(--ease), box-shadow var(--dur-ui) var(--ease); }
.hf-btn .ti { transition: transform var(--dur-ui) var(--ease); }
.hf-btn:hover { transform: translateY(-2px); box-shadow: 0 12px 30px -12px var(--itb-orange); }
.hf-btn:hover .ti { transform: translateX(4px); }
/* nút khoá "Sắp ra mắt" */
.hf-btn.soon { opacity: 0.55; cursor: default; pointer-events: none; }
.hf-soon-tag { font-size: 10.5px; font-weight: 800; letter-spacing: 0.06em; text-transform: uppercase; color: var(--itb-orange);
  border: 1px solid rgba(255,136,29,0.5); border-radius: var(--r-pill); padding: 3.5px 10px; white-space: nowrap; }

/* ---------- Eyebrow --------------------------------------------------------- */
.hf-eye { display: inline-flex; align-items: center; gap: 10px; font-size: 12.5px; font-weight: 800; letter-spacing: 0.18em; text-transform: uppercase; color: var(--itb-teal-mint); }
.hf-eye .bar { width: 24px; height: 2px; background: currentColor; opacity: 0.8; }
/* eyebrow nhỏ cho màn nối tiếp (mobile) */
.hf-mcap { display: inline-flex; align-items: center; gap: 8px; font-size: 11px; font-weight: 800; letter-spacing: 0.18em; text-transform: uppercase; color: var(--itb-teal-mint); }
.hf-mcap .bar { width: 18px; height: 2px; background: currentColor; opacity: 0.8; }
.hf-mhead { margin-bottom: 14px; }
/* chips đặt ngoài ống kính — chỉ dùng trên mobile */
.fxd-chips.fxk-mchips { display: none; }
.fxd-chips .chip.moat { border-color: color-mix(in srgb, var(--tc) 60%, transparent); box-shadow: 0 0 18px -4px var(--tc), inset 0 0 12px -8px var(--tc); }
.fxd-chips .chip .chip-badge { font-style: normal; font-size: 9px; font-weight: 800; letter-spacing: 0.07em; text-transform: uppercase; color: var(--tc); background: color-mix(in srgb, var(--tc) 18%, transparent); padding: 1px 6px; border-radius: 6px; margin-left: 3px; }
.hf-fw-grid.single { grid-template-columns: 1fr; }

/* ---------- Dòng sáng ------------------------------------------------------- */
.flux-stream { fill: none; stroke-linecap: round; }
.flux-base { opacity: 0.055; }
.flux-run { stroke-dasharray: 1 10; opacity: 0.6; }
@media (prefers-reduced-motion: no-preference) { .flux-run { animation: hfFlow 2.4s linear infinite; } }
@keyframes hfFlow { to { stroke-dashoffset: -65; } }
.hf-root svg .glow { filter: drop-shadow(0 0 2px currentColor); }
.hf-conv, .hf-fork { position: absolute; inset: 0; z-index: 1; }
.hf-fork { opacity: 0.5; }

/* ---------- Nhãn nhánh sáng (màn 5) ------------------------------------------ */
.hf-lanetags { position: absolute; inset: 0; z-index: 2; pointer-events: none; }
.hf-lanetags > span { position: absolute; display: inline-flex; align-items: center; gap: 7px;
  font-size: 10.5px; font-weight: 800; letter-spacing: 0.16em; text-transform: uppercase; opacity: 0.6; white-space: nowrap; }
.hf-lanetags > span::before { content: ''; width: 6px; height: 6px; border-radius: 50%; background: currentColor; box-shadow: 0 0 9px currentColor; flex: none; }
.hf-lanetags > span.v { writing-mode: vertical-rl; }
@media (max-width: 1080px) { .hf-lanetags { display: none; } }

/* ---------- Node sáng (orb) -------------------------------------------------- */
.hf-orb { position: absolute; border-radius: 50%; display: grid; place-items: center; color: var(--itb-teal); z-index: 2; }
.hf-orb .core { position: absolute; inset: 0; border-radius: 50%;
  background: radial-gradient(circle at 40% 38%, #d8fff7, var(--itb-teal) 42%, rgba(99,219,198,0.15) 72%); box-shadow: 0 0 70px -10px var(--itb-teal); }
@media (prefers-reduced-motion: no-preference) {
  .hf-orb .ring { position: absolute; inset: 0; border-radius: 50%; border: 1.5px solid currentColor; animation: hfPulse 2.6s var(--ease) infinite; }
}
@keyframes hfPulse { 0% { transform: scale(1); opacity: 0.8; } 80%, 100% { transform: scale(2.4); opacity: 0; } }

/* ---------- NAV thanh ngang full-width, cố định (fixed) ---------------------- */
.fxn { position: fixed; top: 14px; left: 50%; transform: translateX(-50%); width: max-content; max-width: calc(100vw - 28px); z-index: 80;
  display: flex; align-items: center; gap: 14px;
  padding: 7px 8px 7px 16px; border-radius: var(--r-pill, 999px);
  background: rgba(12,4,32,0.72); border: 1px solid rgba(255,255,255,0.12);
  backdrop-filter: blur(14px) saturate(130%); box-shadow: 0 14px 40px rgba(0,0,0,0.5); }
.fxn-brand { display: flex; align-items: center; gap: 9px; cursor: pointer; padding-right: 6px; }
.fxn-brand img { height: 30px; display: block; }   /* logo MÀU — không filter */
.fxn-brand b { font-size: 14.5px; font-weight: 800; color: #fff; line-height: 1.05; letter-spacing: -0.01em; }
.fxn-brand .dotcom { color: var(--itb-teal-mint); font-weight: 700; }
.fxn-nav { display: flex; align-items: center; gap: 2px; }
.fxn-link { display: inline-flex; align-items: center; gap: 5px; font-size: 13.5px; font-weight: 700; color: rgba(255,255,255,0.78);
  padding: 9px 13px; border-radius: var(--r-pill); cursor: pointer; white-space: nowrap;
  transition: background var(--dur-micro) var(--ease), color var(--dur-micro) var(--ease); }
.fxn-link:hover { background: rgba(255,255,255,0.09); color: #fff; }
.fxn-drop { position: relative; }
.fxn-menu { position: absolute; top: calc(100% + 10px); left: 50%; transform: translateX(-50%); min-width: 300px; z-index: 90;
  background: rgba(16,6,40,0.94); border: 1px solid rgba(255,255,255,0.13); border-radius: 18px; padding: 8px;
  backdrop-filter: blur(16px); box-shadow: 0 24px 60px rgba(0,0,0,0.6); }
.fxn-menu::before { content: ''; position: absolute; top: -10px; left: 0; right: 0; height: 10px; } /* cầu hover */
.fxn-mrow { display: grid; gap: 2px; padding: 10px 12px; border-radius: 12px; cursor: pointer; transition: background var(--dur-micro) var(--ease); }
.fxn-mrow:hover { background: rgba(255,255,255,0.07); }
.fxn-mrow .t { display: inline-flex; align-items: center; gap: 7px; font-size: 14px; font-weight: 700; color: #fff; }
.fxn-mrow .s { font-size: 12px; color: rgba(255,255,255,0.55); }
.fxn-mrow.road { cursor: default; }
.fxn-mrow.road .t { color: rgba(255,255,255,0.5); }
.fxn-live { width: 7px; height: 7px; border-radius: 50%; background: var(--itb-teal); box-shadow: 0 0 8px var(--itb-teal); flex: none; }
.fxn-mtag { font-size: 10px; font-weight: 800; letter-spacing: 0.06em; color: var(--itb-orange);
  border: 1px solid rgba(255,136,29,0.5); border-radius: var(--r-pill); padding: 1.5px 7px; }
.fxn-actions { display: flex; align-items: center; gap: 6px; }
.fxn-ghost { border: 1.5px solid rgba(255,255,255,0.3); background: transparent; color: #fff; font-family: inherit;
  font-size: 13px; font-weight: 700; border-radius: var(--r-pill); padding: 8.5px 16px; cursor: pointer;
  transition: background var(--dur-micro) var(--ease); }
.fxn-ghost:hover { background: rgba(255,255,255,0.1); }
.fxn-cta { border: 0; background: var(--itb-orange); color: #2a1200; font-family: inherit; font-size: 13px; font-weight: 800;
  border-radius: var(--r-pill); padding: 9.5px 17px; cursor: pointer; white-space: nowrap;
  transition: transform var(--dur-micro) var(--ease), box-shadow var(--dur-micro) var(--ease); }
.fxn-cta:hover { transform: translateY(-1px); box-shadow: 0 10px 24px -10px var(--itb-orange); }
.fxn-burger { display: none; border: 0; background: transparent; color: #fff; font-size: 22px; padding: 6px 8px; cursor: pointer; }
/* mobile sheet */
.fxn-sheet { position: fixed; left: 12px; right: 12px; top: 74px; z-index: 79; border-radius: 20px; padding: 14px;
  background: rgba(14,5,36,0.97); border: 1px solid rgba(255,255,255,0.13); box-shadow: 0 30px 70px rgba(0,0,0,0.65);
  display: none; max-height: calc(100dvh - 96px); overflow-y: auto; }
.fxn-sheet.open { display: block; }
.fxn-sheet .grp { font-size: 11.5px; font-weight: 800; letter-spacing: 0.16em; text-transform: uppercase; color: rgba(255,255,255,0.5); margin: 12px 6px 6px; }
.fxn-sheet .lnk { display: block; font-size: 15px; font-weight: 600; color: #fff; padding: 9px 6px; border-radius: 10px; cursor: pointer; }
.fxn-sheet .lnk:hover { background: rgba(255,255,255,0.07); }
.fxn-sheet .lnk.road { color: rgba(255,255,255,0.45); }

/* ---------- 01 · HERO --------------------------------------------------------- */
.hf-hero-grid { display: grid; grid-template-columns: 1.05fr 0.95fr; align-items: center; gap: 20px; }
.hf-kick { display: inline-flex; align-items: center; gap: 9px; margin-bottom: 26px; font-size: 12px; font-weight: 800;
  letter-spacing: 0.15em; text-transform: uppercase; color: var(--itb-teal-mint);
  border: 1px solid rgba(99,219,198,0.28); border-radius: var(--r-pill); padding: 8px 16px; background: rgba(99,219,198,0.06); }
.hf-kick .d { width: 7px; height: 7px; border-radius: 50%; background: var(--itb-teal); box-shadow: 0 0 10px var(--itb-teal); }
.hf-h1 { margin: 0; letter-spacing: -0.03em; line-height: 1.06; }
.hf-h1 .lead { display: block; font-size: clamp(20px, 2.4vw, 30px); font-weight: 500; color: rgba(255,255,255,0.66); margin-bottom: 8px; }
.hf-h1 .main { display: block; font-size: clamp(34px, 5vw, 66px); font-weight: 800; color: #fff; }
.hf-h1 .sys { position: relative; display: inline-block; color: var(--itb-teal-mint); text-shadow: 0 0 40px rgba(99,219,198,0.6); white-space: nowrap; }
.hf-h1 .sys::after { content: ''; position: absolute; left: 0; right: 0; bottom: -0.1em; height: 4px; border-radius: 4px;
  background: linear-gradient(90deg, var(--itb-teal), var(--itb-orange)); box-shadow: 0 0 18px rgba(99,219,198,0.7);
  transform: scaleX(0); transform-origin: left; }
.hf-hero.is-active .hf-h1 .sys::after { animation: hfDraw 0.8s var(--ease) 0.9s forwards; }
@keyframes hfDraw { to { transform: scaleX(1); } }
@media (prefers-reduced-motion: reduce) { .hf-h1 .sys::after { transform: scaleX(1); } }
.hf-hero .hf-orb { top: 42%; left: 74%; width: 128px; height: 128px; transform: translate(-50%, -50%); }
.hf-stat { position: absolute; right: clamp(24px, 6vw, 88px); bottom: 84px; text-align: right; max-width: 320px; z-index: 6; }
.hf-stat::before { content: ''; display: block; margin-left: auto; margin-bottom: 14px; width: 54px; height: 2px; border-radius: 2px;
  background: linear-gradient(90deg, var(--itb-teal), var(--itb-orange)); opacity: 0.65; box-shadow: 0 0 12px rgba(99,219,198,0.5); }
.hf-stat .v { font-size: clamp(30px, 3.4vw, 44px); font-weight: 800; color: #fff; letter-spacing: -0.02em; line-height: 1; }
.hf-stat .v small { font-size: 0.5em; font-weight: 700; color: var(--itb-teal-mint); margin-left: 6px; letter-spacing: 0; }
.hf-stat .lb { font-size: 13.5px; color: rgba(255,255,255,0.72); margin-top: 8px; line-height: 1.4; }
.hf-stat .src { font-size: 11.5px; color: rgba(255,255,255,0.44); margin-top: 6px; font-style: italic; }
.hf-stat .note { font-size: 13px; color: rgba(255,255,255,0.78); line-height: 1.5; margin-top: 13px; }
.hf-stat .note::before { content: ''; display: block; width: 26px; height: 1px; background: rgba(255,255,255,0.28); margin: 0 0 9px auto; }
.hf-scroll-hint { position: absolute; bottom: 26px; left: 50%; transform: translateX(-50%); z-index: 6;
  color: rgba(255,255,255,0.5); font-size: 26px; background: none; border: 0; cursor: pointer; }
@media (prefers-reduced-motion: no-preference) { .hf-scroll-hint .ti { animation: hfBounce 1.8s var(--ease) infinite; display: inline-block; } }
@keyframes hfBounce { 0%,100% { transform: translateY(0); opacity: 0.5; } 50% { transform: translateY(7px); opacity: 1; } }

/* ---------- 02 · FRAMEWORK (2 tấm so le mép sáng) ------------------------------ */
.hf-fw-head { max-width: 720px; margin-bottom: 34px; }
.hf-title { font-size: clamp(27px, 3.4vw, 44px); font-weight: 800; color: #fff; letter-spacing: -0.02em; line-height: 1.12; margin: 12px 0 0; }
.hf-sub { font-size: 15.5px; color: rgba(255,255,255,0.6); margin-top: 12px; }
.hf-fw-grid { display: grid; grid-template-columns: 1.04fr 0.96fr; gap: clamp(24px, 4vw, 56px); align-items: start; }
.hf-plane { position: relative; padding: 30px 34px; border-radius: 26px;
  background: radial-gradient(130% 130% at 30% 0%, color-mix(in srgb, var(--pc, #bfa3f5) 13%, rgba(255,255,255,0.03)), rgba(255,255,255,0.012) 62%);
  backdrop-filter: blur(3px); }
.hf-plane::before { content: ''; position: absolute; top: 0; left: 8%; right: 8%; height: 1.5px; border-radius: 2px;
  background: linear-gradient(90deg, transparent, color-mix(in srgb, var(--pc, #bfa3f5) 85%, #fff 10%), transparent); opacity: 0.85;
  box-shadow: 0 0 16px color-mix(in srgb, var(--pc, #bfa3f5) 60%, transparent); }
.hf-fw-grid .hf-plane.far { transform: scale(0.97); transform-origin: top left; margin-top: 54px; }
.hf-plane .tag { display: inline-flex; align-items: center; gap: 8px; font-size: 11.5px; font-weight: 800; letter-spacing: 0.22em; text-transform: uppercase; color: var(--pc); }
.hf-plane .tag .ti { font-size: 16px; }
.hf-plane h3 { font-size: clamp(20px, 2.2vw, 26px); font-weight: 800; color: #fff; margin: 12px 0 16px; line-height: 1.15; }
.hf-pts { display: grid; gap: 12px; margin-bottom: 16px; }
.hf-pt { display: flex; gap: 12px; align-items: flex-start; font-size: 15.5px; line-height: 1.5; color: rgba(255,255,255,0.85); }
.hf-pt .ti { color: var(--pc); font-size: 19px; flex: none; margin-top: 2px; }
.hf-note { font-size: 14px; color: rgba(255,255,255,0.62); line-height: 1.55; margin: 0 0 18px; }
.hf-note b { color: #fff; }
.hf-link { display: inline-flex; align-items: center; gap: 8px; font-size: 15px; font-weight: 700; color: var(--pc); cursor: pointer; background: none; border: 0; padding: 0; font-family: inherit; }
.hf-link .ti { transition: transform var(--dur-ui) var(--ease); }
.hf-link:hover .ti { transform: translateX(4px); }

/* ---------- 03 · WORKSPACE (dòng sông 3 buổi) ----------------------------------- */
.hf-ws-head { max-width: 900px; margin-bottom: 10px; }
.hf-ws-title { font-size: clamp(24px, 3vw, 40px); font-weight: 800; color: #fff; line-height: 1.16; letter-spacing: -0.02em; margin: 12px 0 0; }
.hf-ws-title .big { color: var(--itb-red); }
.hf-pre { display: inline-flex; align-items: center; gap: 14px; margin: 30px 0 8px; font-size: 17.5px; color: rgba(255,255,255,0.88); }
.hf-pre .tag { font-size: 13px; font-weight: 800; letter-spacing: 0.12em; color: var(--itb-teal-mint); border: 1px dashed rgba(99,219,198,0.5); border-radius: var(--r-pill); padding: 6px 15px; }
.hf-pre b { color: #fff; }
.hf-river { position: relative; margin-top: 20px; padding: 30px 0 10px; }
.hf-riversvg { position: absolute; inset: 0; z-index: 0; }
.hf-way { display: grid; grid-template-columns: repeat(3, 1fr) 0.9fr; gap: clamp(16px, 3vw, 42px); position: relative; z-index: 3; align-items: start; }
.hf-wp { display: grid; gap: 12px; justify-items: start; padding-top: 60px; position: relative; }
.hf-wp .node { position: absolute; top: 0; left: 8px; width: 46px; height: 46px; border-radius: 50%; display: grid; place-items: center;
  background: radial-gradient(circle at 40% 38%, color-mix(in srgb, var(--wc) 60%, #fff 10%), color-mix(in srgb, var(--wc) 30%, #1a0838));
  box-shadow: 0 0 26px -8px var(--wc); border: 1px solid var(--wc); }
.hf-wp .node .ti { font-size: 22px; color: #12122a; }
.hf-wp .step { font-size: 13px; font-weight: 800; letter-spacing: 0.1em; text-transform: uppercase; color: var(--wc); }
.hf-wp .txt { font-size: 16.5px; color: #fff; line-height: 1.45; }
.hf-basin { padding-top: 30px; }
.hf-basin .cap { font-size: 12px; font-weight: 800; letter-spacing: 0.12em; text-transform: uppercase; color: var(--itb-orange); }
.hf-basin .items { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.hf-basin .chip { font-size: 13px; font-weight: 700; color: #fff; padding: 7px 14px; border-radius: var(--r-pill); background: rgba(255,136,29,0.16); border: 1px solid rgba(255,136,29,0.4); }
.hf-pilot { display: flex; align-items: center; gap: 20px; flex-wrap: wrap; justify-content: space-between; margin-top: 30px; position: relative; z-index: 3;
  padding: 20px 26px; border-radius: var(--r-xl); background: rgba(255,136,29,0.1); border: 1px solid rgba(255,136,29,0.3); }
.hf-pilot p { font-size: 16px; color: #fff; line-height: 1.5; margin: 0; max-width: 640px; }
.hf-pilot p b { color: var(--itb-orange); }

/* ---------- 04 · KHÁM PHÁ (ống kính lật) ----------------------------------------- */
.hf-disc-head { text-align: center; max-width: 780px; margin: 0 auto 12px; }
.fxk-stage { position: relative; display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: clamp(14px, 2.6vw, 40px); margin-top: 6px; z-index: 5; }
.fxk-link { position: absolute; left: 0; right: 0; top: 50%; height: 90px; width: 100%; transform: translateY(-50%); z-index: 0; pointer-events: none; }
.fxk-btn { position: relative; z-index: 2; display: inline-flex; align-items: center; gap: 10px; background: color-mix(in srgb, var(--kc) 8%, transparent);
  border: 0; cursor: pointer; font-family: inherit; color: rgba(255,255,255,0.75); font-size: 13px; font-weight: 800; letter-spacing: 0.12em; text-transform: uppercase;
  padding: 13px 22px; border-radius: var(--r-pill); box-shadow: inset 0 0 0 1.5px color-mix(in srgb, var(--kc) 40%, transparent); transition: all 0.25s var(--ease); }
.fxk-btn .d { width: 9px; height: 9px; border-radius: 50%; background: var(--kc); opacity: 0.45; transition: all 0.25s var(--ease); flex: none; }
.fxk-btn:hover { color: #fff; transform: translateY(-2px); box-shadow: inset 0 0 0 1.5px color-mix(in srgb, var(--kc) 70%, transparent); }
.fxk-btn.on { color: var(--kc); background: color-mix(in srgb, var(--kc) 16%, transparent); box-shadow: inset 0 0 0 1.5px var(--kc), 0 8px 26px -12px var(--kc); }
.fxk-btn.on .d { opacity: 1; box-shadow: 0 0 12px var(--kc); transform: scale(1.15); }
@media (prefers-reduced-motion: no-preference) { .fxk-btn:not(.on) .d { animation: fxkInvite 2s var(--ease) infinite; } }
@keyframes fxkInvite { 0%, 100% { opacity: 0.35; box-shadow: none; } 50% { opacity: 1; box-shadow: 0 0 10px var(--kc); } }
.fxk-lens { position: relative; width: min(56vh, 480px); aspect-ratio: 1; margin: 0 auto; display: grid; place-items: center; z-index: 1; }
.fxk-lens .rings { position: absolute; inset: 0; width: 100%; height: 100%; }
@media (prefers-reduced-motion: no-preference) {
  .fxk-lens .rot { animation: fxkRot 90s linear infinite; transform-origin: 50% 50%; }
  .fxk-lens .rings { animation: fxkRingIn 0.5s var(--ease); }
  .fxk-core { animation: fxkIn 0.45s var(--ease); }
}
@keyframes fxkRot { to { transform: rotate(360deg); } }
@keyframes fxkRingIn { from { transform: scale(0.96); opacity: 0.5; } to { transform: scale(1); opacity: 1; } }
@keyframes fxkIn { from { opacity: 0; transform: translateY(10px) scale(0.98); } to { opacity: 1; transform: none; } }
.fxk-core { position: relative; z-index: 2; text-align: center; max-width: 76%; display: grid; gap: 10px; justify-items: center; }
.fxk-core .tag { display: inline-flex; align-items: center; gap: 8px; font-size: 11.5px; font-weight: 800; letter-spacing: 0.18em; text-transform: uppercase; }
.fxk-core .tag .ti { font-size: 16px; }
.fxk-core h3 { font-size: clamp(26px, 2.8vw, 38px); font-weight: 800; color: #fff; margin: 0; letter-spacing: -0.02em; }
.fxk-core p { font-size: 14px; color: rgba(255,255,255,0.68); line-height: 1.5; margin: 0; }
.fxk-core .fxd-chips { justify-content: center; margin-bottom: 4px; }
.fxk-core .fxd-chips .chip { font-size: 11.5px; padding: 5px 12px; }
.fxk-hint { display: flex; align-items: center; justify-content: center; gap: 8px; margin-top: 14px; position: relative; z-index: 5;
  font-size: 12.5px; font-weight: 600; color: rgba(255,255,255,0.5); }
.fxk-hint .ti { font-size: 16px; color: var(--itb-teal-mint); }
@media (prefers-reduced-motion: no-preference) { .fxk-hint .ti { animation: fxkInvite 2s var(--ease) infinite; } }
.fxd-chips { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 20px; }
.fxd-chips .chip { display: inline-flex; align-items: center; gap: 6px; font-size: 12.5px; font-weight: 700; color: #fff; padding: 6px 14px; border-radius: var(--r-pill);
  background: color-mix(in srgb, var(--tc) 13%, transparent); box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--tc) 45%, transparent); }
.fxd-chips .chip .ti { font-size: 14px; color: var(--tc); }

/* ---------- 05 · KẾT NỐI (footer khép vòng) -------------------------------------- */
.hf-ftr-head { text-align: center; margin-bottom: clamp(30px, 6vh, 54px); position: relative; z-index: 5; }
.hf-ftr-tagline { font-size: clamp(24px, 3.2vw, 44px); font-weight: 800; color: #fff; letter-spacing: -0.02em; line-height: 1.18; margin: 6px 0 0; }
.hf-ftr-tagline .hl { color: var(--itb-teal-mint); text-shadow: 0 0 36px rgba(99,219,198,0.45); }
.hf-ftr-grid { display: grid; grid-template-columns: 1.2fr 0.9fr 0.95fr 1.15fr; gap: clamp(24px, 3.6vw, 54px); position: relative; z-index: 5; align-items: start; }
.hf-ftr-brand { display: flex; align-items: center; gap: 11px; cursor: pointer; }
.hf-ftr-brand img { height: 40px; display: block; }   /* logo MÀU */
.hf-ftr-brand b { color: #fff; font-weight: 800; font-size: 17px; line-height: 1.08; }
.hf-ftr .desc { font-size: 14.5px; color: rgba(255,255,255,0.66); line-height: 1.6; margin: 16px 0 18px; }
.hf-ftr .desc b { color: #fff; }
.hf-social { display: flex; gap: 9px; }
.hf-social a { display: grid; place-items: center; width: 38px; height: 38px; border-radius: 50%; color: #fff; cursor: pointer;
  background: rgba(255,255,255,0.07); box-shadow: inset 0 0 0 1px rgba(255,255,255,0.15); transition: background var(--dur-micro) var(--ease); }
.hf-social a:hover { background: rgba(99,219,198,0.2); }
.hf-ftr h5 { font-size: 12px; font-weight: 800; letter-spacing: 0.18em; text-transform: uppercase; color: rgba(255,255,255,0.55); margin: 6px 0 14px; }
.hf-ftr h5 .soon { font-size: 10px; letter-spacing: 0.08em; color: var(--itb-orange); border: 1px solid rgba(255,136,29,0.5); border-radius: var(--r-pill); padding: 2px 8px; margin-left: 8px; vertical-align: 1px; }
.hf-ftr ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 11px; }
.hf-ftr ul a { font-size: 14.5px; color: rgba(255,255,255,0.82); cursor: pointer; text-decoration: none; transition: color var(--dur-micro) var(--ease); }
.hf-ftr ul a:hover { color: var(--itb-teal-mint); }
.hf-ftr ul a.soon { color: rgba(255,255,255,0.45); cursor: default; }
.hf-form { position: relative; border-radius: 18px; padding: 18px 20px 20px; background: rgba(255,255,255,0.05); backdrop-filter: blur(8px);
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.12); }
.hf-form::before { content: ''; position: absolute; top: 0; left: 8%; right: 8%; height: 2px; border-radius: 2px;
  background: linear-gradient(90deg, transparent, var(--itb-orange), transparent); opacity: 0.85; }
.hf-form .fh { display: flex; align-items: center; gap: 8px; font-size: 13.5px; font-weight: 800; color: #fff; margin-bottom: 13px; }
.hf-form .fh .ti { color: var(--itb-orange); }
.hf-form form { display: grid; gap: 9px; }
.hf-in { width: 100%; box-sizing: border-box; background: rgba(255,255,255,0.07); border: 1px solid rgba(255,255,255,0.16); border-radius: 10px;
  padding: 10.5px 13px; color: #fff; font: inherit; font-size: 13.5px; }
.hf-in::placeholder { color: rgba(255,255,255,0.42); }
.hf-in:focus { outline: none; border-color: rgba(99,219,198,0.6); }
.hf-ftr-bar { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; position: relative; z-index: 5;
  margin-top: clamp(26px, 5vh, 48px); padding-top: 18px; border-top: 1px solid rgba(255,255,255,0.12);
  font-size: 13px; color: rgba(255,255,255,0.5); }
.hf-ftr-bar a { color: rgba(255,255,255,0.75); cursor: pointer; }
.hf-ftr .hf-conv { opacity: 0.7; }
.hf-ftr .hf-orb { top: 20%; left: 82%; width: 88px; height: 88px; }

/* ---------- Responsive ------------------------------------------------------------ */
@media (max-width: 1080px) {
  .fxn-nav .fxn-link { padding: 9px 9px; font-size: 13px; }
  .hf-ftr-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 920px) {
  .fxn { padding: 9px 14px; }
  .fxn-nav, .fxn-ghost, .fxn-cta { display: none; }
  .fxn-burger { display: block; }
}
@media (max-width: 820px) {
  /* 1 vuốt = 1 màn: giữ snap CỨNG trên mobile (màn đã được tách/nén vừa viewport) */
  .hf-host { scroll-snap-type: y mandatory; }
  .hf-wrap { padding: 80px 20px 34px; }
  .hf-w, .hf-rise { opacity: 1 !important; transform: none !important; }

  /* HERO nén */
  .hf-hero-grid { grid-template-columns: 1fr; }
  .hf-kick { margin-bottom: 14px; font-size: 11px; padding: 7px 13px; }
  .hf-h1 .lead { font-size: 16px; margin-bottom: 6px; }
  .hf-h1 .main { font-size: clamp(26px, 7.4vw, 34px); }
  .hf-hero .hf-orb { left: 84% !important; top: 20% !important; width: 80px !important; height: 80px !important; }
  .hf-rhythm { font-size: 12px; gap: 8px; }
  .hf-rhythm .bead { width: 8px; height: 8px; }
  .hf-btn { font-size: 14.5px; padding: 12px 22px; }
  .hf-stat { position: static; text-align: left; margin-top: 20px; max-width: none; padding: 0; }
  .hf-stat::before { margin-left: 0; margin-bottom: 8px; width: 40px; }
  .hf-stat .v { font-size: 26px; }
  .hf-stat .lb { font-size: 12px; margin-top: 5px; }
  .hf-stat .src { font-size: 10.5px; margin-top: 4px; }
  .hf-stat .note { font-size: 12px; margin-top: 10px; }
  .hf-stat .note::before { margin: 0 auto 7px 0; }
  .hf-scroll-hint { display: none; }

  /* FRAMEWORK nén (mỗi màn 1 tấm) */
  .hf-fw-head { margin-bottom: 16px; }
  .hf-title { font-size: clamp(21px, 6vw, 25px); }
  .hf-sub { font-size: 13.5px; margin-top: 8px; }
  .hf-fw-grid { grid-template-columns: 1fr; }
  .hf-fw-grid .hf-plane.far { transform: none; margin-top: 0; }
  .hf-plane { padding: 18px 18px 20px; }
  .hf-plane h3 { font-size: 18px; margin: 8px 0 10px; }
  .hf-pts { gap: 8px; margin-bottom: 12px; }
  .hf-pt { font-size: 14px; gap: 9px; }
  .hf-pt .ti { font-size: 16px; }
  .hf-note { font-size: 13px; margin-bottom: 12px; }
  .hf-link { font-size: 14px; }

  /* WORKSPACE nén (tách 2 màn) */
  .hf-ws-title { font-size: clamp(19px, 5.6vw, 23px); }
  .hf-pre { font-size: 14px; gap: 10px; margin: 14px 0 4px; }
  .hf-pre .tag { font-size: 11px; padding: 4px 10px; }
  .hf-river { margin-top: 8px; padding: 10px 0 0; }
  .hf-riversvg { display: none; }
  .hf-way { grid-template-columns: 1fr; gap: 18px; }
  .hf-wp { padding-top: 0; padding-left: 54px; gap: 6px; }
  .hf-wp .node { top: -2px; left: 0; width: 40px; height: 40px; }
  .hf-wp .node .ti { font-size: 18px; }
  .hf-wp .step { font-size: 11.5px; }
  .hf-wp .txt { font-size: 14.5px; }
  .hf-basin { padding-top: 4px; padding-left: 54px; }
  .hf-basin .cap { font-size: 11px; }
  .hf-basin .chip { font-size: 11.5px; padding: 5px 11px; }
  .hf-pilot { margin-top: 16px; padding: 14px 16px; gap: 12px; }
  .hf-pilot p { font-size: 13.5px; }
  .hf-pilot .hf-btn { font-size: 13.5px; padding: 10px 18px; }

  /* EXPLORATION: ống kính nhỏ + chips chuyển xuống dưới lens */
  .hf-disc-head .hf-title { font-size: clamp(19px, 5.4vw, 23px) !important; }
  .fxk-stage { grid-template-columns: 1fr 1fr; gap: 8px; margin-top: 2px; }
  .fxk-lens { grid-column: 1 / -1; grid-row: 2; width: min(72vw, 290px); }
  .fxk-btn { padding: 9px 10px; justify-content: center; font-size: 11px; letter-spacing: 0.08em; }
  .fxk-link { display: none; }
  .fxk-core { max-width: 84%; gap: 7px; }
  .fxk-core .tag { font-size: 10px; }
  .fxk-core h3 { font-size: 22px; }
  .fxk-core p { font-size: 12.5px; }
  .fxk-core .fxd-chips { display: none; }
  .fxk-core .hf-btn.soon { font-size: 13px; padding: 10px 16px; }
  .hf-soon-tag { font-size: 9.5px; padding: 3px 8px; }
  .fxd-chips.fxk-mchips { display: flex; justify-content: center; margin: 12px 0 0; gap: 6px; }
  .fxk-mchips .chip { font-size: 11px; padding: 4px 10px; }
  .fxk-hint { font-size: 11px; margin-top: 10px; }

  /* CONNECTION nén (tách 2 màn) */
  .hf-ftr-head { margin-bottom: 18px; }
  .hf-ftr-tagline { font-size: clamp(20px, 5.8vw, 25px); }
  .hf-ftr-grid { grid-template-columns: 1fr; gap: 20px; }
  .hf-ftr-brand img { height: 34px; }
  .hf-ftr .desc { font-size: 13.5px; margin: 12px 0 12px; }
  .hf-social a { width: 34px; height: 34px; }
  .hf-ftr h5 { font-size: 11px; margin: 2px 0 10px; }
  .hf-ftr ul { gap: 8px; }
  .hf-ftr ul a { font-size: 13.5px; }
  .hf-form { padding: 14px 16px 16px; }
  .hf-form .fh { font-size: 12.5px; margin-bottom: 10px; }
  .hf-in { padding: 9px 11px; font-size: 12.5px; }
  .hf-form .hf-btn { font-size: 14px; padding: 11px 18px; }
  .hf-ftr-bar { margin-top: 16px; padding-top: 12px; font-size: 11.5px; }
  .hf-ftr .hf-orb, .hf-ftr .hf-conv { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  .hf-w, .hf-rise { opacity: 1 !important; transform: none !important; transition: none !important; }
  .hf-host { scroll-behavior: auto; }
}