:root{
  --bg-1: #E6F0FF;
  --bg-2: #F6FBFF;
  --accent-1:#8BC7FF;
  --accent-2:#9FE4FF;
  --accent-3:#F0C8FF;
  --accent-4:#B8F1EA;
  --text:#1b263b;
  --muted:#3d4c63;
  --zalo:#0A66FF;
  --hotline:#ff4d4f;
  --card-bg: rgba(255,255,255,0.48);
  --blur: 16px;
  --radius: 16px;
  --shadow: 0 10px 24px rgba(27,38,59,0.10);
  --shadow-strong: 0 14px 32px rgba(27,38,59,0.18);
}

*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial, "Noto Sans", "Apple Color Emoji","Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji", sans-serif;
  color:var(--text);
  background: linear-gradient(160deg, var(--bg-2), var(--bg-1));
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
.container{
  max-width: 920px;
  margin: 0 auto;
  padding: 20px clamp(16px, 4vw, 32px) calc(16px + env(safe-area-inset-right));
  padding-left: calc(16px + env(safe-area-inset-left));
}

.bg{
  position: fixed;
  inset: 0;
  overflow: hidden;
  z-index:-1;
}
.bg-blob{
  position:absolute;
  filter: blur(60px);
  opacity:0.72;
  border-radius:50%;
  transform: translateZ(0);
}
.blob-1{ width:38vw; height:38vw; left:-10vw; top:-8vw; background: radial-gradient(circle at 30% 30%, var(--accent-1), transparent 60%); animation: float1 22s ease-in-out infinite;}
.blob-2{ width:42vw; height:42vw; right:-12vw; top:18vh; background: radial-gradient(circle at 60% 40%, var(--accent-2), transparent 65%); animation: float2 26s ease-in-out infinite;}
.blob-3{ width:48vw; height:48vw; left:10vw; bottom:-14vw; background: radial-gradient(circle at 40% 60%, var(--accent-3), transparent 70%); animation: float3 28s ease-in-out infinite;}
@keyframes float1{
  0%{ transform: translate(0,0) scale(1) }
  50%{ transform: translate(14px,-10px) scale(1.05) }
  100%{ transform: translate(0,0) scale(1) }
}
@keyframes float2{
  0%{ transform: translate(0,0) scale(1) }
  50%{ transform: translate(-16px,8px) scale(1.06) }
  100%{ transform: translate(0,0) scale(1) }
}
@keyframes float3{
  0%{ transform: translate(0,0) scale(1) }
  50%{ transform: translate(10px,12px) scale(1.04) }
  100%{ transform: translate(0,0) scale(1) }
}

.hero{
  text-align: center;
  padding-top: clamp(16px, 4vh, 32px);
  padding-bottom: 8px;
}
.headline{
  font-size: clamp(22px, 5.8vw, 40px);
  line-height: 1.2;
  margin: 28px 0 12px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
  text-shadow: 0 1px 0 rgba(255,255,255,0.6);
}
.sublead{
  margin: 0 auto;
  max-width: 760px;
  font-size: clamp(15px, 4.2vw, 18px);
  line-height: 1.7;
  color: var(--muted);
}

.section-title{
  font-size: clamp(18px, 4.8vw, 22px);
  margin: 28px 0 16px;
  font-weight: 700;
}
.section-title{ position: relative; display: inline-block; }
.section-title::after{
  content:"";
  position:absolute;
  left:50%;
  transform: translateX(-50%);
  bottom:-6px;
  width: 120px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-1), var(--accent-4), var(--accent-3));
  border-radius: 2px;
  opacity: 0.85;
}

.cards{
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}
@media (min-width: 680px){
  .cards{ grid-template-columns: 1fr 1fr; gap: 16px; }
}
.card{
  background: var(--card-bg);
  backdrop-filter: blur(var(--blur));
  -webkit-backdrop-filter: blur(var(--blur));
  border: 1px solid rgba(255,255,255,0.5);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 16px 18px;
  line-height: 1.7;
  color: var(--text);
  transition: transform .2s ease, box-shadow .2s ease, background-color .2s ease, border-color .2s ease;
  outline: none;
  position: relative;
  overflow: hidden;
}
.card::after{
  content:"";
  position:absolute;
  inset:0;
  background: linear-gradient(180deg, rgba(255,255,255,0.35), transparent 60%);
  opacity:0.0;
  transition: opacity .2s ease;
  pointer-events:none;
}
.card:hover,
.card:focus-visible,
.card.active{
  transform: translateY(-2px);
  box-shadow: var(--shadow-strong);
  border-color: rgba(255,255,255,0.7);
}
.card:hover::after,
.card:focus-visible::after,
.card.active::after{ opacity: 1; }

.actions{
  margin-top: 18px;
}
.action-buttons{
  display:grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
@media (min-width: 640px){
  .action-buttons{ grid-template-columns: 1fr 1fr; }
}
.action{
  display:flex;
  flex-direction: column;
  align-items: center;
  text-align:center;
}
.btn{
  display: inline-flex;
  align-items: center;
  gap: 10px;
  justify-content: center;
  width: 100%;
  max-width: 560px;
  padding: 14px 18px;
  border-radius: calc(var(--radius) + 6px);
  border: none;
  color: #fff;
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.2px;
  box-shadow: 0 12px 26px rgba(10,102,255,0.22);
  transition: transform .15s ease, box-shadow .15s ease, filter .15s ease, background-position .3s ease;
  will-change: transform;
  background-size: 200% 100%;
}
.btn:hover,
.btn:focus-visible{
  transform: translateY(-1px);
  filter: brightness(1.02);
  background-position: 100% 0;
}
.btn:active{
  transform: translateY(0);
  filter: brightness(0.98);
}
.btn .icon{
  display:inline-flex;
  width: 22px; height:22px;
}
.btn-zalo{ background: linear-gradient(90deg, var(--zalo), #2b7bff); }
.btn-hotline{
  background: linear-gradient(90deg, var(--hotline), #ff6b6d);
  box-shadow: 0 12px 26px rgba(255,77,79,0.25);
}
.note{
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.trust{
  margin-top: 12px;
}
.trust-box{
  background: var(--card-bg);
  backdrop-filter: blur(var(--blur));
  -webkit-backdrop-filter: blur(var(--blur));
  border: 1px solid rgba(255,255,255,0.5);
  border-radius: var(--radius);
  padding: 16px 18px;
  box-shadow: var(--shadow);
  color: var(--muted);
  line-height: 1.7;
}

.footer{
  text-align: center;
  padding-bottom: calc(12px + env(safe-area-inset-bottom));
  color: #4f5d75;
}
.footer small{
  opacity:0.8;
}

@media (prefers-reduced-motion: no-preference){
  .card{
    animation: floatIn .6s ease both;
  }
  .card:nth-child(2){ animation-delay: .06s }
  .card:nth-child(3){ animation-delay: .12s }
  .card:nth-child(4){ animation-delay: .18s }
  @keyframes floatIn{
    from{ opacity:0; transform: translateY(6px) }
    to{ opacity:1; transform: translateY(0) }
  }
}

:focus-visible{
  outline: 3px solid rgba(10,102,255,0.35);
  outline-offset: 2px;
}

@media (max-width: 399px){
  .btn{ font-size: 15px; padding: 13px 16px; }
}

.quick-help{
  position: fixed;
  right: 16px;
  bottom: calc(16px + env(safe-area-inset-bottom));
  z-index: 50;
  background: linear-gradient(90deg, #ffc9de, #c7f2ff, #e4d6ff);
  color: #3a3a3a;
  border: none;
  padding: 12px 16px;
  border-radius: 999px;
  box-shadow: 0 10px 24px rgba(0,0,0,0.12);
  font-weight: 700;
  letter-spacing: .2px;
  cursor: pointer;
  transition: transform .15s ease, box-shadow .15s ease, filter .2s ease;
  background-size: 200% 100%;
}
.quick-help:hover,
.quick-help:focus-visible{
  transform: translateY(-1px);
  box-shadow: 0 14px 28px rgba(0,0,0,0.16);
  background-position: 100% 0;
}
.quick-help:active{ transform: translateY(0) }

.modal{
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  visibility: hidden;
  opacity: 0;
  transition: opacity .25s ease, visibility .25s ease;
  z-index: 60;
}
.modal.show{
  visibility: visible;
  opacity: 1;
}
.modal-backdrop{
  position: absolute;
  inset: 0;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  background: rgba(0,0,0,0.08);
}
.modal-dialog{
  position: relative;
  width: min(92vw, 520px);
  background: rgba(255,255,255,0.7);
  border: 1px solid rgba(255,255,255,0.6);
  border-radius: 18px;
  box-shadow: 0 24px 56px rgba(27,38,59,0.22);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  padding: 18px 18px 16px;
  transform: scale(0.96);
  opacity: 0;
  transition: transform .22s cubic-bezier(.2,.8,.2,1), opacity .22s ease;
}
.modal.show .modal-dialog{
  transform: scale(1.02);
  opacity: 1;
  animation: pop .28s cubic-bezier(.2,.8,.2,1) forwards;
}
@keyframes pop{
  0%{ transform: scale(0.96) }
  70%{ transform: scale(1.028) }
  100%{ transform: scale(1.0) }
}
.modal-title{
  margin: 6px 0 8px;
  font-size: 20px;
  font-weight: 700;
  color: var(--text);
}
.modal-text{
  margin: 0 0 12px;
  color: var(--muted);
  line-height: 1.6;
}
.modal-actions{
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}
@media (min-width: 520px){
  .modal-actions{ grid-template-columns: 1fr 1fr; }
}
.modal-close{
  position: absolute;
  right: 8px;
  top: 6px;
  background: transparent;
  border: none;
  font-size: 28px;
  line-height: 1;
  color: #6b7280;
  cursor: pointer;
  padding: 6px 10px;
  border-radius: 10px;
  transition: background-color .15s ease, transform .1s ease;
}
.modal-close:hover{ background: rgba(0,0,0,0.06) }
.modal-close:active{ transform: scale(0.96) }