/* Montserrat variable (400-800), tu host de bo CSS chan render tu Google Fonts.
   Khong khai bao subset latin-ext: 8 ky tu tieng Viet kich hoat no (ư đ ơ Ư ỷ ă ĩ Đ)
   deu da nam trong subset vietnamese, nen no chi lam ton them 70 KB. */
@font-face {
  font-family: Montserrat;
  font-style: normal;
  font-weight: 400 800;
  font-display: swap;
  src: url(/fonts/montserrat-vietnamese.woff2) format("woff2");
  unicode-range: U+0102-0103, U+0110-0111, U+0128-0129, U+0168-0169, U+01A0-01A1,
    U+01AF-01B0, U+0300-0301, U+0303-0304, U+0308-0309, U+0323, U+0329, U+1EA0-1EF9, U+20AB;
}
@font-face {
  font-family: Montserrat;
  font-style: normal;
  font-weight: 400 800;
  font-display: swap;
  src: url(/fonts/montserrat-latin.woff2) format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC,
    U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

:root {
  --navy: #185079;
  --navy-dark: #103a59;
  --navy-deep: #0d2d45;
  --cream: #fbf6f1;
  --white: #ffffff;
  --ink: #1f2d3a;
  --muted: #5f7284;
  --line: rgba(24, 80, 121, .16);
  --radius: 14px;
  --shadow: 0 10px 30px rgba(16, 58, 89, .10);
  --shadow-lg: 0 18px 48px rgba(16, 58, 89, .18);
  --wrap: 1180px;
  --header-h: 68px;
  --ease-out: cubic-bezier(.16, 1, .3, 1);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 12px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: Montserrat, "Segoe UI", system-ui, -apple-system, sans-serif;
  color: var(--ink);
  background: var(--cream);
  line-height: 1.65;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; }

.wrap { width: min(100% - 32px, var(--wrap)); margin-inline: auto; }
.wrap.narrow { width: min(100% - 32px, 860px); }

.skip-link {
  position: absolute; left: -9999px; top: 0; z-index: 200;
  background: var(--navy); color: #fff; padding: 12px 20px; border-radius: 0 0 8px 0;
}
.skip-link:focus { left: 0; }

:where(a, button, input, select, textarea):focus-visible {
  outline: 3px solid #7fb4dc; outline-offset: 2px; border-radius: 4px;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 90;
  background: var(--navy);
  min-height: var(--header-h);
  display: flex; align-items: center;
  transition: box-shadow .25s, background .25s;
}
.site-header.scrolled { box-shadow: 0 6px 24px rgba(13, 45, 69, .28); }

.header-inner { display: flex; align-items: center; gap: 18px; width: min(100% - 32px, var(--wrap)); }

.brand { flex: 0 0 auto; display: flex; align-items: center; }
.brand img {
  height: 34px; width: auto;
  filter: brightness(0) invert(1);
}

.nav { margin-left: auto; display: flex; gap: 26px; }
.nav a {
  color: #e4eef6; text-decoration: none; font-size: .86rem;
  font-weight: 600; letter-spacing: .02em; padding: 6px 0;
  border-bottom: 2px solid transparent; white-space: nowrap;
  transition: color .2s, border-color .2s;
}
.nav a:hover, .nav a.active { color: #fff; border-color: #fff; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  font: inherit; font-weight: 700; text-decoration: none; cursor: pointer;
  border: 0; border-radius: 999px; padding: 12px 24px;
  transition: transform .18s, box-shadow .18s, background .18s, color .18s;
}
.btn svg { width: 17px; height: 17px; fill: currentColor; }
.btn:hover { transform: translateY(-2px); }

.btn-call-head {
  background: #fff; color: var(--navy); font-size: .84rem;
  padding: 9px 18px; flex: 0 0 auto;
}
.btn-call-head:hover { box-shadow: 0 8px 20px rgba(0, 0, 0, .25); }

.btn-primary { background: var(--navy); color: #fff; box-shadow: var(--shadow); }
.btn-primary:hover { background: var(--navy-dark); box-shadow: var(--shadow-lg); }

.btn-ghost { background: transparent; color: var(--navy); border: 2px solid var(--navy); }
.btn-ghost:hover { background: var(--navy); color: #fff; }

.nav-toggle {
  display: none; flex-direction: column; justify-content: center; gap: 5px;
  width: 42px; height: 38px; background: transparent; border: 0; cursor: pointer; padding: 0;
}
.nav-toggle span {
  display: block; height: 2px; background: #fff; border-radius: 2px;
  transition: transform .28s, opacity .2s;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero { background: var(--cream); padding-top: 54px; }
.hero-head { text-align: center; }
.hero-eyebrow {
  margin: 0 0 10px; text-transform: uppercase; letter-spacing: .22em;
  font-size: .68rem; font-weight: 700; color: var(--muted);
}
.hero-title {
  margin: 0; font-size: clamp(2rem, 7.5vw, 4.2rem); line-height: 1.05;
  font-weight: 700; letter-spacing: .07em; color: var(--navy);
}
.hero-sub {
  margin: 16px auto 0; max-width: 580px;
  font-size: clamp(.98rem, 2.2vw, 1.18rem); color: var(--muted);
}
.hero-cta { display: flex; flex-wrap: wrap; gap: 14px; justify-content: center; margin: 28px 0 44px; }

.hero-media { width: 100%; aspect-ratio: 16 / 7; overflow: hidden; }
.hero-media img { width: 100%; height: 100%; object-fit: cover; object-position: center 55%; }

/* ---------- Tagline ---------- */
.tagline { background: var(--cream); padding: 40px 0 10px; }
.tagline-inner {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: center;
  gap: 18px 28px; text-align: center;
}
.tagline-text {
  margin: 0; font-size: clamp(1.3rem, 4vw, 2.2rem); font-weight: 500;
  letter-spacing: .02em; color: var(--navy);
}
.tagline-text strong { font-weight: 800; }
.tagline-contact {
  margin: 0; background: var(--navy); color: #fff; border-radius: 999px;
  padding: 10px 22px; font-weight: 700; font-size: clamp(.82rem, 2.2vw, 1rem);
}
.tagline-contact a { color: #fff; text-decoration: none; }
.tagline-contact a:hover { text-decoration: underline; }

.showcase { background: var(--cream); padding: 30px 0 10px; }
.showcase img { display: block; width: 100%; height: auto; border-radius: var(--radius); box-shadow: var(--shadow); }

/* ---------- Sections ---------- */
.section { padding: 72px 0; }
.section-alt { background: #f4ece4; }

.section-title {
  margin: 0 0 14px; text-align: center; color: var(--navy);
  font-size: clamp(1.4rem, 4.2vw, 2.1rem); font-weight: 700; letter-spacing: .09em;
  text-transform: uppercase;
}
.section-title::after {
  content: ""; display: block; width: 62px; height: 3px; margin: 14px auto 0;
  background: var(--navy); border-radius: 2px;
}
.section-sub { margin: 0 0 38px; text-align: center; color: var(--muted); }

.lead { text-align: center; font-size: 1.04rem; color: #41545f; margin: 26px 0 34px; }
.values-label { text-align: center; font-weight: 700; color: var(--navy); margin: 0 0 24px; }

.values { list-style: none; margin: 0; padding: 0; display: grid; gap: 16px; }
.values li {
  display: flex; gap: 16px; align-items: flex-start;
  background: #fff; border-radius: var(--radius); padding: 20px 22px;
  box-shadow: var(--shadow); border-left: 4px solid var(--navy);
}
.values li p { margin: 0; }
.values-icon {
  flex: 0 0 auto; width: 40px; height: 40px; border-radius: 50%;
  background: rgba(24, 80, 121, .1); display: grid; place-items: center;
}
.values-icon svg { width: 21px; height: 21px; fill: var(--navy); }

/* ---------- Clients ---------- */
.clients {
  list-style: none; margin: 0 0 26px; padding: 0;
  display: flex; flex-wrap: wrap; justify-content: center; gap: 14px;
}
.clients li {
  background: var(--cream); border-radius: 12px; border: 1px solid var(--line);
  flex: 0 0 calc(50% - 7px); padding: 16px; aspect-ratio: 5 / 3;
  min-width: 0; overflow: hidden;
}
.clients img {
  width: 100%; height: 100%; object-fit: contain;
  filter: grayscale(1); opacity: .72;
  transition: filter .3s, opacity .3s, transform .3s;
}
.clients li:hover img { filter: none; opacity: 1; transform: scale(1.06); }
.clients-note { text-align: center; font-weight: 700; color: var(--navy); margin: 0; }

/* ---------- Services ---------- */
.services {
  list-style: none; margin: 0; padding: 0;
  display: grid; grid-template-columns: 1fr; gap: 18px;
}
.service {
  position: relative; border-radius: var(--radius); overflow: hidden;
  box-shadow: var(--shadow); aspect-ratio: 3 / 2; background: #dfe7ee;
}
.service img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform .5s ease;
}
.service:hover img { transform: scale(1.07); }
.service::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(to top, rgba(13, 45, 69, .62), transparent 52%);
}

.chip {
  position: absolute; left: 14px; bottom: 14px; z-index: 2;
  background: var(--navy); color: #fff; font-size: .74rem; font-weight: 700;
  letter-spacing: .06em; padding: 7px 15px; border-radius: 6px;
}

/* ---------- Projects ---------- */
.project { margin-bottom: 48px; position: relative; }
.project:last-child { margin-bottom: 0; }

.project-bar {
  display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
  background: var(--navy); color: #fff; padding: 12px 16px;
  border-radius: 10px 10px 0 0;
}
.project-logo {
  flex: 0 0 auto; height: 36px; width: auto; background: #fff;
  border-radius: 6px; padding: 4px 8px; object-fit: contain;
}
.project-bar h3 {
  flex: 1 1 240px; margin: 0; font-size: .86rem; font-weight: 700;
  letter-spacing: .03em; text-transform: uppercase; line-height: 1.45;
}
.project-link {
  flex: 0 0 auto; color: #fff; font-size: .78rem; font-weight: 700;
  text-decoration: underline; text-underline-offset: 3px; white-space: nowrap;
}
.project-link:hover { color: #bcdcf3; }

.gallery {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 6px;
  background: var(--navy); padding: 6px; border-radius: 0 0 10px 10px;
}
.shot {
  flex: 0 1 calc(50% - 3px); padding: 0; border: 0; cursor: zoom-in; overflow: hidden;
  background: #11405f; position: relative; aspect-ratio: 3 / 2; border-radius: 3px;
}
.shot img { width: 100%; height: 100%; object-fit: cover; transition: transform .45s, opacity .3s; }
.shot:hover img { transform: scale(1.06); opacity: .88; }

.chip-tag { position: static; display: inline-block; margin-top: 10px; }

/* ---------- Behind the scenes ---------- */
.bts { background: var(--cream); padding-top: 20px; }
.bts-mosaic {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 3px;
  width: min(100% - 24px, var(--wrap)); margin-inline: auto;
}
.bts-mosaic .shot {
  flex: 0 0 calc(33.333% - 2px); aspect-ratio: 1 / 1;
  border-radius: 0; cursor: zoom-in;
}
.bts-band { background: var(--navy); margin-top: -1px; padding: 30px 16px; text-align: center; }
.bts-band h2 {
  margin: 0; color: #fff; font-size: clamp(1.15rem, 4vw, 1.9rem);
  font-weight: 700; letter-spacing: .18em;
}

/* ---------- Short video ---------- */
.shorts {
  list-style: none; margin: 0; padding: 0;
  display: grid; grid-template-columns: 1fr; gap: 22px;
}
.short-card {
  display: block; position: relative; text-decoration: none;
  border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow);
  transition: transform .25s, box-shadow .25s;
  /* width co dinh: de auto thi be rong the phu thuoc anh lazy -> the sap xuong 0px */
  width: 100%; max-width: 540px; margin-inline: auto;
}
a.short-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.short-card img { display: block; width: 100%; height: auto; }
.short-go {
  position: absolute; inset: 0;
  display: flex; align-items: center; justify-content: center;
  background: rgba(13, 45, 69, .72);
  color: #fff; font-weight: 700; font-size: 1rem; letter-spacing: .05em;
  opacity: 0; transition: opacity .25s;
}
a.short-card:hover .short-go, a.short-card:focus-visible .short-go { opacity: 1; }

/* ---------- Contact ---------- */
.contact { background: var(--navy); color: #eaf2f8; padding: 64px 0 0; }
.contact-grid { display: grid; grid-template-columns: 1fr; gap: 44px; }
.contact-info h2 {
  margin: 0 0 20px; font-size: clamp(1.6rem, 5vw, 2.4rem);
  letter-spacing: .14em; font-weight: 700; color: #fff; text-transform: uppercase;
}
.contact-logo { height: 52px; width: auto; filter: brightness(0) invert(1); margin-bottom: 26px; }

.contact-list { list-style: none; margin: 0 0 24px; padding: 0; display: grid; gap: 14px; }
.contact-list li { display: grid; gap: 2px; }
.contact-list span {
  font-size: .7rem; text-transform: uppercase; letter-spacing: .14em; color: #9dc0d8;
}
.contact-list a {
  color: #fff; text-decoration: none; font-weight: 700; font-size: 1.04rem; word-break: break-word;
}
.contact-list a:hover { text-decoration: underline; }

.contact-social { list-style: none; margin: 0 0 24px; padding: 0; display: flex; flex-wrap: wrap; gap: 10px; }
.contact-social a {
  display: inline-block; border: 1px solid rgba(255, 255, 255, .4);
  border-radius: 999px; padding: 7px 18px; font-size: .82rem;
  font-weight: 600; text-decoration: none; transition: background .2s, border-color .2s;
}
.contact-social a:hover { background: #fff; color: var(--navy); border-color: #fff; }

.contact-company { font-weight: 800; letter-spacing: .06em; margin: 0; color: #fff; }

.contact-form-wrap {
  background: rgba(255, 255, 255, .07); border: 1px solid rgba(255, 255, 255, .16);
  border-radius: var(--radius); padding: 26px;
}
.contact-form-wrap h3 { margin: 0 0 18px; font-size: 1.1rem; color: #fff; }
.contact-form { display: grid; gap: 14px; }
.contact-form label { display: grid; gap: 6px; font-size: .8rem; font-weight: 600; color: #cfe2ef; }
.contact-form input, .contact-form select, .contact-form textarea {
  font: inherit; font-size: .94rem; color: var(--ink);
  padding: 11px 13px; border-radius: 9px; border: 0; background: #fff; width: 100%;
}
.contact-form textarea { resize: vertical; }
.contact-form .btn { margin-top: 6px; background: #fff; color: var(--navy); }
.contact-form .btn:hover { background: #d9ebf8; }
.hp { position: absolute; left: -9999px; }

/* ---------- Trang cam on sau khi gui form ---------- */
.thanks {
  min-height: 100vh; min-height: 100svh;
  display: grid; place-items: center;
  padding: 32px 16px; background: var(--navy-deep); color: #eaf2f8;
}
.thanks-card {
  width: min(100%, 560px); text-align: center;
  background: rgba(255, 255, 255, .07); border: 1px solid rgba(255, 255, 255, .16);
  border-radius: var(--radius); padding: 44px 32px;
}
.thanks-logo { height: 56px; width: auto; margin: 0 auto 28px; filter: brightness(0) invert(1); }
.thanks-card h1 { margin: 0 0 14px; font-size: clamp(1.35rem, 4vw, 1.75rem); color: #fff; }
.thanks-card p { margin: 0 0 18px; color: #cfe2ef; }
.thanks-urgent { font-weight: 600; }
.thanks-urgent a { color: #fff; }
.thanks-card .btn { margin-top: 10px; background: #fff; color: var(--navy); }
.thanks-card .btn:hover { background: #d9ebf8; }

.copyright {
  margin: 56px 0 0; padding: 18px 16px; text-align: center;
  font-size: .78rem; color: #9dc0d8;
  border-top: 1px solid rgba(255, 255, 255, .14);
}

/* ---------- Floating actions ---------- */
.float-actions {
  position: fixed; right: 16px; bottom: 16px; z-index: 80;
  display: flex; flex-direction: column; gap: 12px;
}
.fab {
  width: 54px; height: 54px; border-radius: 50%;
  display: grid; place-items: center; text-decoration: none;
  color: #fff; font-weight: 800; font-size: .78rem;
  box-shadow: 0 8px 22px rgba(0, 0, 0, .3);
  transition: transform .2s;
}
.fab:hover { transform: scale(1.08); }
.fab svg { width: 25px; height: 25px; fill: #fff; }
.fab-phone { background: #15a34a; animation: ring 2.6s infinite; }
.fab-zalo { background: #0068ff; }

@keyframes ring {
  0%, 72%, 100% { box-shadow: 0 8px 22px rgba(0, 0, 0, .3), 0 0 0 0 rgba(21, 163, 74, .5); }
  36% { box-shadow: 0 8px 22px rgba(0, 0, 0, .3), 0 0 0 14px rgba(21, 163, 74, 0); }
}

/* ---------- Lightbox ---------- */
.lightbox {
  position: fixed; inset: 0; z-index: 120;
  background: rgba(8, 26, 40, .95);
  display: grid; place-items: center; padding: 60px 16px;
}
.lightbox[hidden] { display: none; }
.lb-img {
  max-width: min(94vw, 1100px); max-height: 80vh;
  width: auto; border-radius: 8px; box-shadow: 0 24px 70px rgba(0, 0, 0, .6);
}
.lb-close, .lb-nav {
  position: absolute; background: rgba(255, 255, 255, .12); color: #fff;
  border: 0; cursor: pointer; border-radius: 50%; line-height: 1;
  transition: background .2s;
}
.lb-close:hover, .lb-nav:hover { background: rgba(255, 255, 255, .3); }
.lb-close { top: 18px; right: 18px; width: 44px; height: 44px; font-size: 2rem; }
.lb-nav { top: 50%; transform: translateY(-50%); width: 52px; height: 52px; font-size: 2.4rem; }
.lb-prev { left: 12px; }
.lb-next { right: 12px; }
.lb-caption {
  position: absolute; bottom: 18px; left: 50%; transform: translateX(-50%);
  margin: 0; color: #cfe2ef; font-size: .84rem; text-align: center;
  max-width: 90vw; padding: 0 12px;
}

/* ---------- Reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ---------- Chu truot len khoi mat na ---------- */
/* .mask cat phan chu con nam duoi duong chan; chu ben trong truot tu duoi len.
   padding-bottom bu cho phan nhu cua chu tron (O, S) khoi bi cat mat. */
.mask {
  display: inline-block; overflow: hidden; vertical-align: bottom;
  padding-bottom: .12em; margin-bottom: -.12em;
}
.mask > span { display: inline-block; }

/* Hero chay ngay khi tai trang, khong cho cuon.
   fill-mode backwards chu KHONG phai both: both se khoa transform o gia tri cuoi,
   lam .btn:hover { transform: translateY(-2px) } mat tac dung. */
@keyframes fade-in { from { opacity: 0; } }
@keyframes rise-in { from { transform: translateY(120%); } }
@keyframes fade-in-up { from { opacity: 0; transform: translateY(18px); } }
@keyframes settle-in { from { transform: scale(1.07); } }

/* Mac dinh chi mo dan — khong dich chuyen. Day cung la thu ma nguoi dung
   bat "tat hieu ung chuyen dong" se thay. */
.hero-eyebrow { animation: fade-in .8s var(--ease-out) .05s backwards; }
.hero-title .mask > span { animation: fade-in .95s var(--ease-out) backwards; }
.hero-title .mask:nth-child(1) > span { animation-delay: .12s; }
.hero-title .mask:nth-child(2) > span { animation-delay: .24s; }
.hero-title .mask:nth-child(3) > span { animation-delay: .36s; }
.hero-sub { animation: fade-in .9s var(--ease-out) .56s backwards; }
.hero-cta .btn:nth-child(1) { animation: fade-in .8s var(--ease-out) .70s backwards; }
.hero-cta .btn:nth-child(2) { animation: fade-in .8s var(--ease-out) .80s backwards; }

/* Nang cap len chuyen dong that cho nguoi khong tat hieu ung */
@media (prefers-reduced-motion: no-preference) {
  .hero-eyebrow, .hero-sub, .hero-cta .btn { animation-name: fade-in-up; }
  .hero-title .mask > span { animation-name: rise-in; }
  .hero-media img { animation: settle-in 1.8s var(--ease-out) backwards; }

  /* Tieu de muc: JS tach chu roi gan .split nen bo hieu ung mo dan cua .reveal,
     thay bang tung chu truot len. Khong co media nay thi .reveal lo dan nhu cu. */
  .reveal.split { opacity: 1; transform: none; }
  .split .mask > span { transform: translateY(120%); transition: transform .85s var(--ease-out); }
  .split.visible .mask > span { transform: translateY(0); }
}

/* ---------- Responsive ---------- */
@media (min-width: 560px) {
  .clients li { flex-basis: calc(33.333% - 10px); }
  .bts-mosaic .shot { flex-basis: calc(20% - 2.4px); }
}

@media (min-width: 720px) {
  .services { grid-template-columns: repeat(2, 1fr); }
  .values { grid-template-columns: repeat(3, 1fr); }
  .values li { flex-direction: column; }
  .gallery { gap: 8px; padding: 8px; }
  .shot { flex-basis: calc(33.333% - 6px); }
  .shorts { grid-template-columns: repeat(2, 1fr); align-items: start; }
  .contact-grid { grid-template-columns: 1.05fr .95fr; gap: 56px; }
  .project-bar { padding: 14px 20px; }
  .project-bar h3 { font-size: .94rem; }
}

@media (min-width: 1000px) {
  .clients li { flex-basis: calc(20% - 12px); }
  .services { grid-template-columns: repeat(3, 1fr); }
  .bts-mosaic .shot { flex-basis: calc(14.2857% - 2.58px); }
  .hero { padding-top: 70px; }
  .hero-media { aspect-ratio: 21 / 8; }
}

@media (max-width: 860px) {
  .nav {
    position: fixed; inset: var(--header-h) 0 auto 0;
    flex-direction: column; gap: 0;
    background: var(--navy-dark); padding: 0 20px;
    max-height: 0; overflow: hidden;
    transition: max-height .35s ease, padding .35s ease;
    box-shadow: 0 16px 30px rgba(0, 0, 0, .3);
  }
  .nav.open { max-height: 70vh; padding: 10px 20px 20px; }
  .nav a { padding: 13px 0; border-bottom: 1px solid rgba(255, 255, 255, .12); font-size: .95rem; }
  .nav a:hover, .nav a.active { border-color: rgba(255, 255, 255, .12); }
  .nav-toggle { display: flex; }
  .btn-call-head { margin-left: auto; }
  .btn-call-head span { display: none; }
}

@media (max-width: 420px) {
  .btn-call-head { font-size: 0; padding: 9px 12px; gap: 0; }
  .btn-call-head svg { width: 19px; height: 19px; }
}

/* Moi chuyen dong deu nam trong @media (prefers-reduced-motion: no-preference)
   o tren, nen o day chi can bo not phan dich chuyen cua .reveal va cuon muot.
   Co y KHONG dung "*{ animation-duration: .001ms }" nhu truoc: no giet luon
   ca hieu ung mo dan, lam trang chet cung voi nguoi tat hieu ung he thong. */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { transform: none; }
}