/* ==========================================================
   Sáng kiến số – Landing page
   Mobile-first, no build step, no framework.
   ========================================================== */

:root {
  --ink: #1e1b4b;
  --ink-2: #3f3d6b;
  --muted: #5b5a7d;
  --bg: #fbfaff;
  --bg-alt: #f3f0ff;
  --card: #ffffff;
  --line: #e6e1fb;

  --indigo: #4338ca;
  --violet: #7c3aed;
  --magenta: #db2777;
  --pink: #ec4899;
  --orange: #f97316;
  --sun: #fbbf24;
  --green: #16a34a;
  --teal: #0d9488;
  --sky: #0ea5e9;

  --grad-main: linear-gradient(100deg, #4338ca 0%, #7c3aed 38%, #db2777 72%, #f97316 100%);
  --grad-btn: linear-gradient(100deg, #6d28d9 0%, #c026d3 55%, #f97316 100%);

  --radius: 20px;
  --radius-sm: 12px;
  --shadow: 0 10px 30px -12px rgba(67, 56, 202, .25);
  --shadow-lg: 0 24px 60px -20px rgba(67, 56, 202, .35);

  --font: "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  --font-script: "Dancing Script", "Segoe Script", cursive;

  --header-h: 68px;
}

*, *::before, *::after { 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: var(--font);
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--ink);
  background: var(--bg);
  overflow-x: hidden;
}

img, svg { display: block; max-width: 100%; }
.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }
h1, h2, h3 { line-height: 1.2; margin: 0; }
p { margin: 0 0 1em; }
a { color: var(--indigo); }
ul, ol { margin: 0; padding: 0; }

.container { width: min(1200px, 100% - 32px); margin-inline: auto; }

.ic {
  width: 1.25em; height: 1.25em; flex: none;
  fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round;
}

.skip-link {
  position: absolute; left: 12px; top: -60px; z-index: 100;
  padding: 10px 16px; border-radius: 10px; background: var(--ink); color: #fff; text-decoration: none;
}
.skip-link:focus { top: 12px; }

:focus-visible { outline: 3px solid var(--orange); outline-offset: 3px; border-radius: 6px; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .55em;
  padding: .7em 1.3em; border: 0; border-radius: 999px;
  font: inherit; font-weight: 700; font-size: 1rem; line-height: 1.2;
  text-decoration: none; cursor: pointer;
  transition: transform .2s ease, box-shadow .2s ease, background-color .2s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }
.btn-lg { padding: .95em 1.7em; font-size: 1.0625rem; }

.btn-primary {
  color: #fff; background: var(--grad-btn); background-size: 160% 100%;
  box-shadow: 0 12px 28px -10px rgba(192, 38, 211, .6);
  animation: shimmer 6s ease-in-out infinite;
}
.btn-primary:hover { box-shadow: 0 16px 32px -10px rgba(192, 38, 211, .7); }
@keyframes shimmer { 0%, 100% { background-position: 0% 50%; } 50% { background-position: 100% 50%; } }

.btn-ghost {
  color: var(--indigo); background: rgba(255, 255, 255, .75);
  box-shadow: inset 0 0 0 2px rgba(67, 56, 202, .25);
  backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
}
.btn-ghost:hover { background: #fff; }

.btn-white { color: var(--indigo); background: #fff; box-shadow: 0 10px 24px -10px rgba(0, 0, 0, .35); word-break: break-all; }

.btn-login {
  color: #fff; background: var(--indigo);
  padding: .6em 1.15em; font-size: .95rem;
  box-shadow: 0 8px 20px -8px rgba(67, 56, 202, .65);
}
.btn-login:hover { background: #3730a3; }

/* ---------- Header ---------- */
.site-header {
  position: fixed; inset: 0 0 auto 0; z-index: 50; height: var(--header-h);
  transition: background-color .3s ease, box-shadow .3s ease;
}
.site-header.is-scrolled {
  background: rgba(255, 255, 255, .88);
  backdrop-filter: blur(12px) saturate(1.4); -webkit-backdrop-filter: blur(12px) saturate(1.4);
  box-shadow: 0 6px 24px -14px rgba(30, 27, 75, .35);
}
.header-inner { height: 100%; display: flex; align-items: center; gap: 16px; }

.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); margin-right: auto; }
.brand img { width: 40px; height: 40px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-name { font-weight: 900; font-size: 1.15rem; letter-spacing: .01em; text-transform: uppercase; color: var(--indigo); margin: 0; }
.brand-sub { font-weight: 700; font-size: .72rem; letter-spacing: .08em; text-transform: uppercase; color: var(--magenta); margin: 0; }

.header-actions { display: flex; align-items: center; gap: 8px; }

.nav-toggle {
  display: inline-grid; place-items: center; width: 44px; height: 44px;
  border: 0; border-radius: 12px; background: rgba(255, 255, 255, .8); color: var(--ink); cursor: pointer;
}
.nav-toggle .ic { width: 24px; height: 24px; }
.nav-toggle .ic-close { display: none; }
.nav-toggle[aria-expanded="true"] .ic-open { display: none; }
.nav-toggle[aria-expanded="true"] .ic-close { display: block; }

.main-nav {
  position: fixed; top: var(--header-h); left: 0; right: 0;
  background: rgba(255, 255, 255, .97);
  box-shadow: 0 20px 30px -20px rgba(30, 27, 75, .35);
  padding: 8px 16px 20px;
  transform: translateY(-8px); opacity: 0; visibility: hidden;
  transition: transform .25s ease, opacity .25s ease, visibility .25s;
}
.main-nav.is-open { transform: none; opacity: 1; visibility: visible; }
.main-nav ul { list-style: none; display: grid; gap: 2px; }
.main-nav a {
  display: block; padding: 12px 10px; border-radius: 10px;
  color: var(--ink); font-weight: 600; text-decoration: none;
}
.main-nav a:hover, .main-nav a.is-active { color: var(--indigo); background: var(--bg-alt); }

/* No-JS fallback: show the nav inline under the header. */
.no-js .main-nav { position: static; transform: none; opacity: 1; visibility: visible; box-shadow: none; background: none; padding: 0; }
.no-js .nav-toggle { display: none; }

@media (max-width: 420px) {
  .brand-sub { display: none; }
  .btn-login span { display: none; }
  .btn-login { padding: .65em; }
}

@media (min-width: 1000px) {
  .nav-toggle { display: none; }
  .main-nav {
    position: static; transform: none; opacity: 1; visibility: visible;
    background: none; box-shadow: none; padding: 0;
  }
  .main-nav ul { display: flex; gap: 4px; }
  .main-nav a { position: relative; padding: 8px 12px; font-size: .97rem; background: none !important; }
  .main-nav a::after {
    content: ""; position: absolute; left: 12px; right: 12px; bottom: 2px; height: 3px; border-radius: 3px;
    background: var(--grad-main); transform: scaleX(0); transform-origin: left; transition: transform .25s ease;
  }
  .main-nav a:hover::after, .main-nav a.is-active::after { transform: scaleX(1); }
  .brand { margin-right: 0; }
  .main-nav { margin-left: auto; margin-right: 12px; }
  .brand img { width: 44px; height: 44px; }
  .brand-name { font-size: 1.3rem; }
}

/* ---------- Hero ---------- */
.hero {
  position: relative; isolation: isolate; overflow: hidden;
  min-height: 100svh;
  padding: calc(var(--header-h) + 28px) 0 0;
  display: flex; flex-direction: column;
  background: linear-gradient(180deg, #bfe3ff 0%, #dcd6ff 38%, #fde7f3 64%, #ffe9d2 80%, #ffffff 100%);
}

.hero-sky { position: absolute; inset: 0; z-index: -2; pointer-events: none; }
.sun {
  position: absolute; left: 50%; top: 56%; width: 520px; height: 520px; translate: -50% -50%;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 237, 160, .95) 0%, rgba(255, 214, 140, .55) 30%, rgba(255, 190, 200, .2) 55%, transparent 70%);
  animation: glow 7s ease-in-out infinite;
}
@keyframes glow { 0%, 100% { scale: 1; opacity: .9; } 50% { scale: 1.08; opacity: 1; } }

.cloud {
  position: absolute; height: 46px; border-radius: 999px; background: rgba(255, 255, 255, .85);
  filter: blur(.5px);
  animation: drift 60s linear infinite;
}
.cloud::before, .cloud::after { content: ""; position: absolute; background: inherit; border-radius: 50%; }
.cloud::before { width: 60px; height: 60px; left: 22%; top: -28px; }
.cloud::after { width: 44px; height: 44px; left: 52%; top: -18px; }
.c1 { width: 160px; top: 18%; left: -10%; }
.c2 { width: 120px; top: 30%; left: 30%; animation-duration: 85s; animation-delay: -40s; opacity: .7; }
.c3 { width: 180px; top: 12%; left: 70%; animation-duration: 75s; animation-delay: -20s; }
@keyframes drift { from { translate: 0 0; } to { translate: 120vw 0; } }

.hero-scene {
  position: absolute; left: 0; right: 0; bottom: 0; z-index: -1;
  width: 100%; height: clamp(230px, 34vh, 300px);
}
@media (min-width: 760px) { .hero-scene { height: 46%; min-height: 300px; } }
.signal { animation: dash 2.4s linear infinite; }
@keyframes dash { to { stroke-dashoffset: -28; } }

.hero-content { position: relative; text-align: center; padding-bottom: clamp(190px, 26vh, 380px); }
@media (min-width: 760px) { .hero-content { padding-bottom: clamp(220px, 40vh, 380px); } }

.hero-eyebrow {
  display: inline-block; margin: 0 0 18px; padding: 6px 14px; border-radius: 999px;
  background: rgba(255, 255, 255, .75); color: var(--indigo);
  font-weight: 700; font-size: .85rem; letter-spacing: .02em;
  box-shadow: 0 6px 18px -10px rgba(67, 56, 202, .5);
}

.hero-title { display: flex; flex-direction: column; align-items: center; gap: .1em; text-transform: uppercase; }
.hero-title .t1 {
  position: relative; display: inline-block;
  font-size: clamp(2.6rem, 11vw, 6.2rem); font-weight: 900; letter-spacing: -.02em; line-height: 1.05;
  background: var(--grad-main); -webkit-background-clip: text; background-clip: text; color: transparent;
  padding: .08em .04em 0;
  transform: rotate(-3deg);
  filter: drop-shadow(0 6px 0 rgba(255, 255, 255, .75)) drop-shadow(0 14px 22px rgba(67, 56, 202, .25));
}
.t-so { position: relative; }
.burst {
  position: absolute; right: -.32em; top: -.12em; width: .45em; height: .45em;
  background:
    linear-gradient(var(--orange), var(--orange)) 50% 0 / 14% 38% no-repeat,
    linear-gradient(var(--sun), var(--sun)) 100% 45% / 38% 14% no-repeat,
    linear-gradient(var(--pink), var(--pink)) 0 30% / 34% 13% no-repeat;
  transform: rotate(18deg);
  animation: pop 2.8s ease-in-out infinite;
}
@keyframes pop { 0%, 100% { scale: 1; } 50% { scale: 1.2; } }

.hero-title .t2 {
  font-size: clamp(1.45rem, 5.4vw, 3rem); font-weight: 900; color: var(--ink); letter-spacing: .005em;
  transform: rotate(-3deg); margin-top: -.05em;
  text-shadow: 0 3px 0 rgba(255, 255, 255, .8);
}

.hero-script {
  margin: 14px 0 18px; display: flex; flex-wrap: wrap; justify-content: center; gap: .1em .5em;
  font-family: var(--font-script); font-size: clamp(1.7rem, 5.6vw, 2.7rem); font-weight: 700; line-height: 1.2;
  color: var(--indigo); transform: rotate(-3deg);
}
.hero-script .hl { color: var(--magenta); position: relative; }
.hero-script .hl::after {
  content: ""; position: absolute; left: 4%; right: -2%; bottom: -2px; height: 4px; border-radius: 4px;
  background: linear-gradient(90deg, var(--magenta), var(--orange));
}

.hero-lead { max-width: 640px; margin: 0 auto 26px; font-size: clamp(1rem, 2.4vw, 1.15rem); color: var(--ink-2); font-weight: 500; }

.hero-cta { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; }

.deadline-chip {
  display: inline-flex; flex-wrap: wrap; justify-content: center; align-items: center; gap: 6px 10px;
  margin-top: 22px; padding: 10px 18px; border-radius: 16px;
  background: rgba(255, 255, 255, .8); color: var(--ink);
  font-weight: 600; font-size: .95rem;
  box-shadow: 0 10px 24px -14px rgba(30, 27, 75, .45);
  backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
}
.deadline-chip .ic { color: var(--magenta); }
.dc-time { color: var(--magenta); font-weight: 800; }

.float-cards { position: absolute; inset: 0; pointer-events: none; display: none; }
.fcard {
  position: absolute; display: flex; align-items: center; gap: 10px;
  padding: 10px 16px; border-radius: 18px;
  background: rgba(255, 255, 255, .55); color: var(--indigo);
  border: 1.5px solid rgba(255, 255, 255, .9);
  box-shadow: 0 14px 30px -16px rgba(67, 56, 202, .55);
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
  font-weight: 800; font-size: .82rem; text-transform: uppercase; line-height: 1.25; letter-spacing: .02em;
  animation: float 6s ease-in-out infinite;
}
.fcard .ic { width: 30px; height: 30px; }
.fc1 { left: 4%; top: 22%; rotate: -8deg; color: var(--green); }
.fc2 { right: 5%; top: 18%; rotate: 6deg; animation-delay: -1.5s; }
.fc3 { left: 9%; top: 44%; rotate: 5deg; color: var(--magenta); animation-delay: -3s; }
.fc4 { right: 8%; top: 40%; rotate: -5deg; color: var(--orange); animation-delay: -4.5s; }
@keyframes float { 0%, 100% { translate: 0 0; } 50% { translate: 0 -12px; } }

@media (min-width: 1100px) { .float-cards { display: block; } }

.hero-wave { position: absolute; left: 0; right: 0; bottom: -1px; width: 100%; height: 90px; z-index: 1; }

/* ---------- Values ---------- */
.values { position: relative; z-index: 2; margin-top: -28px; }
.values-grid {
  list-style: none; display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px;
  padding: 18px; border-radius: 28px;
  background: rgba(255, 255, 255, .92); box-shadow: var(--shadow-lg);
  border: 1px solid var(--line);
}
.value { text-align: center; padding: 14px 6px; }
.value h3 { font-size: 1.05rem; font-weight: 900; text-transform: uppercase; color: var(--indigo); margin: 12px 0 4px; }
.value p { margin: 0; font-size: .92rem; color: var(--muted); line-height: 1.5; }
.value-ic {
  display: inline-grid; place-items: center; width: 64px; height: 64px; border-radius: 50%; color: #fff;
  box-shadow: 0 10px 22px -10px currentColor;
  transition: transform .3s ease;
}
.value:hover .value-ic { transform: translateY(-4px) rotate(-6deg); }
.value-ic .ic { width: 30px; height: 30px; }
.v-pink { background: radial-gradient(circle at 30% 30%, #f9a8d4, #db2777); }
.v-indigo { background: radial-gradient(circle at 30% 30%, #a5b4fc, #4338ca); }
.v-green { background: radial-gradient(circle at 30% 30%, #86efac, #16a34a); }
.v-orange { background: radial-gradient(circle at 30% 30%, #fdba74, #ea580c); }

@media (min-width: 820px) {
  .values-grid { grid-template-columns: repeat(4, 1fr); padding: 26px 18px; }
  .value + .value { border-left: 1px solid var(--line); }
}

/* ---------- Section basics ---------- */
.section { padding: clamp(64px, 9vw, 112px) 0; position: relative; }
.section-head { text-align: center; max-width: 760px; margin: 0 auto clamp(32px, 5vw, 52px); }
.eyebrow {
  display: inline-block; margin: 0 0 10px; padding: 4px 12px; border-radius: 999px;
  background: #ede9fe; color: var(--violet);
  font-size: .8rem; font-weight: 800; letter-spacing: .1em; text-transform: uppercase;
}
.eyebrow-light { background: rgba(255, 255, 255, .2); color: #fff; }
.section-title { font-size: clamp(1.75rem, 4.4vw, 2.75rem); font-weight: 900; letter-spacing: -.01em; }
.section-lead { margin: 14px 0 0; color: var(--muted); font-size: 1.1rem; }
.grad { background: var(--grad-main); -webkit-background-clip: text; background-clip: text; color: transparent; }

/* ---------- About ---------- */
.about-grid { display: grid; gap: 40px; align-items: center; }
.about-text .section-title { margin-bottom: 20px; }
.about-text p { color: var(--ink-2); }
.official-name {
  padding: 14px 18px; border-left: 4px solid var(--violet); border-radius: 0 12px 12px 0;
  background: var(--bg-alt);
}
.official-name strong { color: var(--indigo); }
.note-soft {
  display: flex; gap: 10px; align-items: flex-start;
  padding: 14px 16px; border-radius: 14px; background: #fff1f2; color: #9f1239 !important; font-weight: 600;
}
.note-soft .ic { color: var(--pink); margin-top: 3px; }

.about-stats { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.stat {
  position: relative; overflow: hidden;
  padding: 22px 18px; border-radius: var(--radius); background: var(--card);
  box-shadow: var(--shadow); border: 1px solid var(--line);
  transition: transform .3s ease;
}
.stat:hover { transform: translateY(-4px); }
.stat::before { content: ""; position: absolute; right: -30px; top: -30px; width: 100px; height: 100px; border-radius: 50%; opacity: .14; background: currentColor; }
.stat-num { display: block; font-size: clamp(2rem, 6vw, 2.6rem); font-weight: 900; line-height: 1.1; }
.stat-label { display: block; margin-top: 6px; font-size: .93rem; color: var(--muted); line-height: 1.45; }
.s-indigo { color: var(--indigo); }
.s-pink { color: var(--magenta); }
.s-green { color: var(--green); }
.s-orange { color: #ea580c; }

@media (min-width: 900px) {
  .about-grid { grid-template-columns: 1.2fr 1fr; gap: 64px; }
  .about-stats { transform: rotate(-1.5deg); }
}

/* ---------- Themes ---------- */
.themes { background: var(--bg-alt); }
.themes::before, .join::before, .awards::before {
  content: ""; position: absolute; inset: 0; pointer-events: none; z-index: 0;
  background-image: radial-gradient(rgba(124, 58, 237, .09) 1.5px, transparent 1.5px);
  background-size: 22px 22px;
  mask-image: linear-gradient(180deg, transparent, #000 20%, #000 80%, transparent);
  -webkit-mask-image: linear-gradient(180deg, transparent, #000 20%, #000 80%, transparent);
}
.section > .container { position: relative; z-index: 1; }

.theme-grid { display: grid; gap: 18px; }
.theme-card {
  padding: 28px 24px; border-radius: var(--radius); background: var(--card);
  box-shadow: var(--shadow); border: 1px solid var(--line);
  transition: transform .3s ease, box-shadow .3s ease;
}
.theme-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.theme-card h3 { font-size: 1.2rem; font-weight: 800; margin: 16px 0 10px; }
.theme-card p { margin: 0; color: var(--muted); }
.theme-ic { display: inline-grid; place-items: center; width: 56px; height: 56px; border-radius: 16px; }
.theme-ic .ic { width: 28px; height: 28px; }
.t-violet { background: #ede9fe; color: var(--violet); }
.t-orange { background: #ffedd5; color: #ea580c; }
.t-teal { background: #ccfbf1; color: var(--teal); }

.theme-note {
  display: flex; gap: 10px; align-items: flex-start; max-width: 820px; margin: 28px auto 0;
  padding: 14px 18px; border-radius: 14px; background: #fff; border: 1.5px dashed #c4b5fd; color: var(--ink-2);
}
.theme-note .ic { color: var(--green); margin-top: 3px; }

@media (min-width: 820px) { .theme-grid { grid-template-columns: repeat(3, 1fr); } }

/* ---------- Join steps ---------- */
.steps { list-style: none; display: grid; gap: 18px; counter-reset: s; }
.step {
  position: relative; padding: 28px 22px 24px; border-radius: var(--radius);
  background: var(--card); box-shadow: var(--shadow); border: 1px solid var(--line);
}
.step-num {
  position: absolute; right: 18px; top: 10px;
  font-size: 3.4rem; font-weight: 900; line-height: 1;
  background: var(--grad-main); -webkit-background-clip: text; background-clip: text; color: transparent; opacity: .25;
}
.step-ic {
  display: inline-grid; place-items: center; width: 54px; height: 54px; border-radius: 50%;
  color: #fff; background: var(--grad-btn); box-shadow: 0 10px 20px -10px rgba(192, 38, 211, .7);
}
.step-ic .ic { width: 26px; height: 26px; }
.step h3 { font-size: 1.15rem; font-weight: 800; margin: 14px 0 8px; }
.step p { margin: 0; color: var(--muted); font-size: .97rem; }

.join-note {
  display: flex; gap: 12px; align-items: flex-start; max-width: 860px; margin: 28px auto 0;
  padding: 16px 20px; border-radius: 16px; background: #eef2ff; color: var(--ink-2);
}
.join-note .ic { color: var(--indigo); margin-top: 3px; }

@media (min-width: 700px) { .steps { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1080px) {
  .steps { grid-template-columns: repeat(4, 1fr); }
  .step:not(:last-child)::after {
    content: ""; position: absolute; top: 54px; right: -18px; width: 18px; height: 3px; border-radius: 3px;
    background: linear-gradient(90deg, #c4b5fd, #f9a8d4);
  }
}

/* ---------- Rules / submission ---------- */
.rules { background: linear-gradient(180deg, var(--bg) 0%, #fff7ed 100%); }
.submit-grid { display: grid; gap: 22px; }
.submit-card {
  padding: 28px 24px; border-radius: 24px; background: var(--card);
  box-shadow: var(--shadow); border: 1px solid var(--line); border-top: 6px solid transparent;
}
.sc-product { border-top-color: var(--violet); }
.sc-video { border-top-color: var(--orange); }
.submit-card header { margin-bottom: 14px; }
.submit-tag {
  display: inline-block; padding: 3px 12px; border-radius: 999px;
  font-size: .78rem; font-weight: 800; text-transform: uppercase; letter-spacing: .08em;
}
.sc-product .submit-tag { background: #ede9fe; color: var(--violet); }
.sc-video .submit-tag { background: #ffedd5; color: #c2410c; }
.submit-card h3 { font-size: 1.45rem; font-weight: 900; margin-top: 8px; }
.submit-card > p { color: var(--ink-2); }

.formats { list-style: none; display: flex; flex-wrap: wrap; gap: 8px; margin: 4px 0 20px; }
.formats li {
  display: inline-flex; align-items: center; gap: 6px; padding: 7px 12px; border-radius: 999px;
  background: var(--bg-alt); color: var(--indigo); font-size: .9rem; font-weight: 600;
  transition: background-color .2s ease, transform .2s ease;
}
.formats li:hover { background: #e0e7ff; transform: translateY(-2px); }
.formats .ic { width: 18px; height: 18px; }

.checks { list-style: none; display: grid; gap: 10px; }
.checks li { display: flex; gap: 10px; align-items: flex-start; font-size: .96rem; color: var(--ink-2); }
.checks .ic { color: var(--green); margin-top: 3px; }

.video-limit {
  display: flex; align-items: center; gap: 10px; padding: 12px 16px; border-radius: 14px;
  background: #fff7ed; color: #9a3412 !important; font-size: 1.05rem;
}
.video-limit .ic { width: 26px; height: 26px; color: var(--orange); }
.video-list { padding-left: 0; list-style: none; counter-reset: v; display: grid; gap: 10px; margin-bottom: 18px; }
.video-list li { counter-increment: v; display: flex; gap: 12px; align-items: flex-start; color: var(--ink-2); font-size: .97rem; }
.video-list li::before {
  content: counter(v); flex: none; display: grid; place-items: center; width: 28px; height: 28px; border-radius: 50%;
  background: linear-gradient(135deg, #fb923c, #db2777); color: #fff; font-weight: 800; font-size: .85rem;
}
.hint { margin: 0; padding: 12px 16px; border-radius: 14px; background: var(--bg-alt); color: var(--ink-2); font-size: .95rem; }

.rules-foot { max-width: 860px; margin: 28px auto 0; text-align: center; color: var(--muted); }

@media (min-width: 900px) { .submit-grid { grid-template-columns: 1.15fr 1fr; } .submit-card { padding: 34px 32px; } }

/* ---------- Timeline ---------- */
.countdown {
  max-width: 640px; margin: 0 auto 44px; padding: 22px 20px; border-radius: 24px; text-align: center;
  color: #fff; background: var(--grad-main); box-shadow: var(--shadow-lg);
}
.cd-title { margin: 0 0 12px; font-weight: 700; }
.cd-units { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; }
.cd-units div { padding: 10px 4px; border-radius: 14px; background: rgba(255, 255, 255, .16); }
.cd-units span { display: block; font-size: clamp(1.6rem, 6vw, 2.4rem); font-weight: 900; line-height: 1.1; font-variant-numeric: tabular-nums; }
.cd-units small { font-size: .82rem; opacity: .9; }

.timeline { list-style: none; position: relative; max-width: 820px; margin: 0 auto; }
.timeline::before {
  content: ""; position: absolute; left: 25px; top: 10px; bottom: 10px; width: 4px; border-radius: 4px;
  background: linear-gradient(180deg, #a5b4fc, #f0abfc, #fdba74);
}
.tl-item { position: relative; display: flex; gap: 18px; padding-bottom: 26px; }
.tl-item:last-child { padding-bottom: 0; }
.tl-dot {
  position: relative; z-index: 1; flex: none; display: grid; place-items: center;
  width: 54px; height: 54px; border-radius: 50%;
  background: #fff; color: var(--violet); border: 3px solid #ddd6fe;
}
.tl-dot .ic { width: 24px; height: 24px; }
.tl-body {
  flex: 1; padding: 16px 20px; border-radius: 18px; background: var(--card);
  box-shadow: var(--shadow); border: 1px solid var(--line);
}
.tl-body h3 { font-size: 1.12rem; font-weight: 800; margin-bottom: 6px; }
.tl-body p { margin: 0; color: var(--muted); font-size: .97rem; }
.tl-body .tl-date { color: var(--magenta); font-weight: 800; font-size: .9rem; margin-bottom: 4px; }

.tl-key .tl-body { border: 2px solid #f9a8d4; background: #fff7fb; }
.tl-key .tl-dot { border-color: #f9a8d4; color: var(--magenta); }

.tl-item.is-done .tl-dot { background: #dcfce7; border-color: #86efac; color: var(--green); }
.tl-item.is-done .tl-body { opacity: .7; }
.tl-item.is-now .tl-dot { background: var(--grad-btn); border-color: #fff; color: #fff; box-shadow: 0 0 0 6px rgba(192, 38, 211, .18); animation: pulse 2s ease-in-out infinite; }
.tl-item.is-now .tl-body::before {
  content: "Đang diễn ra"; display: inline-block; margin-bottom: 6px; padding: 2px 10px; border-radius: 999px;
  background: var(--magenta); color: #fff; font-size: .74rem; font-weight: 800; text-transform: uppercase; letter-spacing: .06em;
}
@keyframes pulse { 0%, 100% { box-shadow: 0 0 0 6px rgba(192, 38, 211, .18); } 50% { box-shadow: 0 0 0 12px rgba(192, 38, 211, .05); } }

/* ---------- Awards ---------- */
.awards { background: var(--bg-alt); }
.prize-grid { display: grid; gap: 16px; align-items: end; max-width: 980px; margin: 0 auto; }
.prize {
  position: relative; text-align: center; padding: 28px 20px; border-radius: 24px; color: #fff;
  box-shadow: var(--shadow-lg); overflow: hidden;
}
.prize::after {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background: linear-gradient(115deg, transparent 35%, rgba(255, 255, 255, .35) 50%, transparent 65%);
  transform: translateX(-100%); animation: sheen 5s ease-in-out infinite;
}
@keyframes sheen { 0%, 60% { transform: translateX(-100%); } 100% { transform: translateX(100%); } }
.p1 { background: linear-gradient(160deg, #f59e0b, #f97316 45%, #db2777); order: -1; }
.p2 { background: linear-gradient(160deg, #6366f1, #7c3aed); }
.p3 { background: linear-gradient(160deg, #14b8a6, #0ea5e9); }
.p2::after { animation-delay: .8s; }
.p3::after { animation-delay: 1.6s; }
.prize-badge {
  display: inline-grid; place-items: center; width: 64px; height: 64px; border-radius: 50%; margin-bottom: 10px;
  background: rgba(255, 255, 255, .22);
}
.prize-badge .ic { width: 34px; height: 34px; }
.prize-rank { display: block; font-size: 1.3rem; font-weight: 900; text-transform: uppercase; letter-spacing: .04em; }
.prize-count { display: inline-block; margin-top: 6px; padding: 2px 12px; border-radius: 999px; background: rgba(255, 255, 255, .22); font-size: .85rem; font-weight: 700; }
.prize-value { margin: 14px 0 0; font-size: 1.1rem; font-weight: 700; }
.prize-value strong { display: block; font-size: 3.4rem; font-weight: 900; line-height: 1; }
.prize-sub { margin: 4px 0 0; font-size: .88rem; opacity: .9; }

@media (min-width: 760px) {
  .prize-grid { grid-template-columns: 1fr 1.15fr 1fr; }
  .p1 { order: 0; padding: 40px 24px 36px; }
  .p1 .prize-value strong { font-size: 4.2rem; }
}

.support-grid { display: grid; gap: 16px; max-width: 980px; margin: 32px auto 0; }
.support {
  display: flex; gap: 16px; align-items: flex-start; padding: 22px; border-radius: 20px;
  background: var(--card); box-shadow: var(--shadow); border: 1px solid var(--line);
}
.support-ic { flex: none; display: grid; place-items: center; width: 50px; height: 50px; border-radius: 14px; background: #fce7f3; color: var(--magenta); }
.support h3 { font-size: 1.08rem; font-weight: 800; margin-bottom: 4px; }
.support p { margin: 0; color: var(--muted); font-size: .97rem; }
@media (min-width: 760px) { .support-grid { grid-template-columns: 1fr 1fr; } }

/* ---------- Principles ---------- */
.pr-grid { list-style: none; display: grid; gap: 18px; }
.pr {
  padding: 26px 22px; border-radius: var(--radius); background: var(--card);
  border: 1px solid var(--line); box-shadow: var(--shadow);
  transition: transform .3s ease;
}
.pr:hover { transform: translateY(-4px); }
.pr > .ic { width: 40px; height: 40px; padding: 8px; border-radius: 12px; }
.pr:nth-child(1) > .ic { background: #fef3c7; color: #b45309; }
.pr:nth-child(2) > .ic { background: #e0e7ff; color: var(--indigo); }
.pr:nth-child(3) > .ic { background: #dcfce7; color: var(--green); }
.pr:nth-child(4) > .ic { background: #fce7f3; color: var(--magenta); }
.pr h3 { font-size: 1.1rem; font-weight: 800; margin: 14px 0 8px; }
.pr p { margin: 0; color: var(--muted); font-size: .96rem; }
@media (min-width: 700px) { .pr-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1080px) { .pr-grid { grid-template-columns: repeat(4, 1fr); } }

/* ---------- FAQ ---------- */
.faq { background: linear-gradient(180deg, var(--bg) 0%, var(--bg-alt) 100%); }
.faq-list { max-width: 820px; margin: 0 auto; display: grid; gap: 12px; }
.faq details {
  border-radius: 16px; background: var(--card); border: 1px solid var(--line); box-shadow: 0 6px 18px -14px rgba(30, 27, 75, .4);
  overflow: hidden;
}
.faq summary {
  list-style: none; cursor: pointer; display: flex; justify-content: space-between; align-items: center; gap: 16px;
  padding: 18px 20px; font-weight: 700; font-size: 1.03rem;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary .ic { color: var(--violet); transition: transform .25s ease; }
.faq details[open] summary .ic { transform: rotate(45deg); }
.faq details[open] summary { color: var(--indigo); }
.faq details p { margin: 0; padding: 0 20px 20px; color: var(--ink-2); }

/* ---------- Contact ---------- */
.contact { padding-top: 0; background: var(--bg-alt); }
.contact-card {
  position: relative; overflow: hidden;
  display: grid; gap: 22px; align-items: center;
  padding: clamp(28px, 5vw, 48px); border-radius: 28px; color: #fff;
  background: var(--grad-main); box-shadow: var(--shadow-lg);
}
.contact-card::before, .contact-card::after {
  content: ""; position: absolute; border-radius: 50%; background: rgba(255, 255, 255, .12); pointer-events: none;
}
.contact-card::before { width: 260px; height: 260px; right: -60px; top: -90px; }
.contact-card::after { width: 160px; height: 160px; left: 40%; bottom: -90px; }
.contact-card h2 { font-size: clamp(1.5rem, 3.6vw, 2.2rem); font-weight: 900; margin-bottom: 8px; }
.contact-card p { margin: 0; opacity: .95; }
.contact-card .btn { position: relative; z-index: 1; justify-self: start; font-size: clamp(.88rem, 3.7vw, 1.0625rem); padding-inline: 1.2em; }
@media (min-width: 900px) { .contact-card { grid-template-columns: 1fr auto; } }

/* ---------- Footer ---------- */
.site-footer { background: var(--ink); color: #c7d2fe; padding: 40px 0 32px; }
.footer-inner { display: grid; gap: 16px; }
.footer-brand { display: flex; align-items: center; gap: 12px; }
.footer-brand .brand-name { color: #fff; }
.footer-brand .brand-sub { color: #f9a8d4; display: block; }
.footer-org { margin: 0; max-width: 720px; font-size: .95rem; }
.footer-copy { margin: 0; font-size: .85rem; opacity: .7; }

/* ---------- Dialog ---------- */
.login-dialog {
  width: min(440px, 100% - 32px); padding: 34px 28px 28px; border: 0; border-radius: 24px;
  text-align: center; color: var(--ink); box-shadow: var(--shadow-lg);
}
.login-dialog::backdrop { background: rgba(30, 27, 75, .45); backdrop-filter: blur(4px); -webkit-backdrop-filter: blur(4px); }
.login-dialog[open] { animation: dialog-in .3s ease; }
@keyframes dialog-in { from { opacity: 0; transform: translateY(16px) scale(.97); } }
.login-dialog h2 { font-size: 1.4rem; font-weight: 900; margin: 14px 0 10px; }
.login-dialog p { color: var(--ink-2); }
.dialog-ic { display: inline-grid; place-items: center; width: 64px; height: 64px; border-radius: 50%; color: #fff; background: var(--grad-btn); }
.dialog-ic .ic { width: 30px; height: 30px; }
.dialog-close {
  position: absolute; right: 12px; top: 12px; width: 40px; height: 40px; display: grid; place-items: center;
  border: 0; border-radius: 50%; background: var(--bg-alt); color: var(--ink); cursor: pointer;
}

/* ---------- Scroll reveal (only when JS is running) ---------- */
.js .reveal { opacity: 0; transform: translateY(26px); transition: opacity .7s ease, transform .7s cubic-bezier(.2, .7, .2, 1); }
.js .reveal.is-visible { opacity: 1; transform: none; }

/* ---------- Respect reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .js .reveal { opacity: 1; transform: none; }
}