/* Trang giới thiệu TinyWorld: cùng phong cách cảnh đêm với cửa sổ Cài đặt của app. */
:root {
  --bg: #0b1424;
  --bg-2: #0f1b33;
  --panel: rgba(22, 36, 68, 0.62);
  --panel-solid: #142240;
  --line: #24365a;
  --line-2: #33497a;
  --text: #eef2fd;
  --text-2: #c9d4ee;
  --muted: #8da3d4;
  --accent: #4f86ff;
  --accent-2: #8fb3ff;
  --warm: #ffcc62;
  --grass: #86c8a4;
  --pink: #ff9fbd;
  --radius: 18px;
  --gutter: 20px;
  color-scheme: dark;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 76px;
}

body {
  margin: 0;
  min-width: 320px;
  background:
    radial-gradient(70% 50% at 85% 0%, #1d3a74 0%, transparent 70%),
    radial-gradient(60% 40% at 0% 30%, #142a55 0%, transparent 70%),
    linear-gradient(180deg, #10203f 0%, var(--bg) 38%, #0a1220 100%);
  background-color: var(--bg);
  color: var(--text);
  font-family: "Be Vietnam Pro", "Segoe UI", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a {
  color: var(--accent-2);
}

h1,
h2,
h3 {
  margin: 0;
  line-height: 1.15;
  letter-spacing: -0.01em;
}

p {
  margin: 0;
}

.symbols {
  position: absolute;
  width: 0;
  height: 0;
  overflow: hidden;
}

.icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

:focus-visible {
  outline: 2px solid #9cc0ff;
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

/* Gợi ý đổi ngôn ngữ khi trình duyệt dùng ngôn ngữ khác trang đang mở. */
.suggest {
  position: relative;
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  padding: 8px 44px 8px var(--gutter);
  background: #1a2c55;
  border-bottom: 1px solid var(--line-2);
  color: var(--text-2);
  font-size: 14px;
  flex-wrap: wrap;
}

.suggest[hidden] {
  display: none;
}

.suggest__go {
  color: var(--text);
  font-weight: 600;
}

.suggest__close {
  position: absolute;
  right: 10px;
  top: 50%;
  width: 30px;
  height: 30px;
  transform: translateY(-50%);
  border: 0;
  border-radius: 8px;
  background: transparent;
  color: var(--muted);
  font-size: 22px;
  line-height: 1;
  cursor: pointer;
}

.suggest__close:hover {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text);
}

/* Thanh trên cùng. */
.nav {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(11, 20, 36, 0.72);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.nav__inner {
  display: flex;
  align-items: center;
  gap: 18px;
  max-width: 1160px;
  margin: 0 auto;
  padding: 10px var(--gutter);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-size: 19px;
  font-weight: 800;
  text-decoration: none;
}

.nav__links {
  display: flex;
  gap: 4px;
  margin-left: auto;
}

.nav__links a,
.nav__lang {
  padding: 6px 12px;
  border-radius: 10px;
  color: var(--text-2);
  font-size: 15px;
  font-weight: 500;
  text-decoration: none;
}

.nav__links a:hover,
.nav__lang:hover {
  background: rgba(255, 255, 255, 0.07);
  color: var(--text);
}

.nav__lang {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  white-space: nowrap;
}

.nav__lang .icon {
  width: 18px;
  height: 18px;
  color: #7fd8be;
}

/* Nút. */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 48px;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: 14px;
  font: inherit;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition:
    transform 0.15s,
    box-shadow 0.15s,
    background 0.15s;
}

.btn--primary {
  background: linear-gradient(180deg, #5f92ff 0%, #3c6ee6 100%);
  color: #fff;
  box-shadow:
    0 10px 30px rgba(79, 134, 255, 0.35),
    inset 0 1px 0 rgba(255, 255, 255, 0.25);
}

.btn--primary:hover {
  transform: translateY(-1px);
  box-shadow:
    0 14px 36px rgba(79, 134, 255, 0.45),
    inset 0 1px 0 rgba(255, 255, 255, 0.25);
}

.btn--ghost {
  border-color: var(--line-2);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
}

.btn--ghost:hover {
  background: rgba(255, 255, 255, 0.08);
}

.btn--small {
  min-height: 38px;
  padding: 0 16px;
  border-radius: 12px;
  background: linear-gradient(180deg, #5f92ff 0%, #3c6ee6 100%);
  color: #fff;
  font-size: 15px;
}

.btn--large {
  min-height: 56px;
  padding: 0 28px;
  font-size: 17px;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.actions--center {
  justify-content: center;
}

/* Đầu trang: chữ ở giữa, màn hình thu nhỏ bên dưới. */
.hero {
  position: relative;
  padding: 56px var(--gutter) 24px;
  text-align: center;
}

.sky {
  position: absolute;
  inset: 0 0 30% 0;
  overflow: hidden;
  pointer-events: none;
}

.star {
  position: absolute;
  border-radius: 50%;
  background: #eef2ff;
  animation: twinkle 4s ease-in-out infinite;
}

.star--gold {
  background: var(--warm);
  box-shadow: 0 0 8px rgba(255, 204, 98, 0.8);
}

@keyframes twinkle {
  50% {
    opacity: 0.25;
  }
}

.hero__text {
  position: relative;
  max-width: 760px;
  margin: 0 auto;
}

.eyebrow {
  display: inline-block;
  margin-bottom: 18px;
  padding: 5px 14px;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  background: rgba(79, 134, 255, 0.1);
  color: var(--accent-2);
  font-size: 14px;
  font-weight: 600;
}

.hero h1 {
  font-size: clamp(2.2rem, 5.6vw, 3.9rem);
  font-weight: 800;
  text-wrap: balance;
}

.hero .lede {
  max-width: 640px;
  margin: 18px auto 28px;
  color: var(--text-2);
  font-size: clamp(1rem, 2.2vw, 1.15rem);
  text-wrap: pretty;
}

.hero .actions {
  justify-content: center;
}

.hero > .hint {
  max-width: 720px;
  margin: 18px auto 0;
  color: var(--muted);
  font-size: 14px;
}

/* Màn hình thu nhỏ: hình nền đêm, hai cửa sổ, taskbar, pet sống trên đó. */
.desk {
  position: relative;
  max-width: 1080px;
  margin: 44px auto 0;
  padding: 10px;
  border: 1px solid #2b3b5e;
  border-radius: 24px;
  background: linear-gradient(180deg, #121c33 0%, #0b1222 100%);
  box-shadow:
    0 40px 90px rgba(0, 0, 0, 0.55),
    0 0 0 1px rgba(255, 255, 255, 0.03) inset;
}

.desk__screen {
  position: relative;
  height: 420px;
  overflow: hidden;
  border-radius: 16px;
  text-align: left;
}

.desk__world {
  position: absolute;
  left: 0;
  top: 0;
  height: 420px;
  transform-origin: 0 0;
  overflow: hidden;
  background:
    radial-gradient(55% 70% at 82% 8%, rgba(58, 99, 184, 0.55) 0%, transparent 70%),
    linear-gradient(180deg, #16295a 0%, #102043 55%, #0d1a35 100%);
  user-select: none;
  -webkit-user-select: none;
  touch-action: pan-y;
}

.desk__wallpaper {
  position: absolute;
  right: 0;
  bottom: 44px;
  width: 78%;
  height: 72%;
}

.desk__moon {
  position: absolute;
  right: 9%;
  top: 34px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, #fff8dc 0%, #ffe9a8 60%, #f5d27a 100%);
  box-shadow: 0 0 40px 10px rgba(255, 220, 140, 0.25);
}

.desk__world .star {
  animation-duration: 5s;
}

/* Cửa sổ kiểu Windows 11, nền sáng. Vị trí do desk.js đặt. */
.win {
  position: absolute;
  left: 0;
  top: 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border-radius: 9px;
  background: #fbfbfd;
  color: #1f2430;
  box-shadow:
    0 14px 36px rgba(0, 0, 0, 0.5),
    0 0 0 1px rgba(0, 0, 0, 0.45);
  transition:
    opacity 0.18s,
    transform 0.18s,
    visibility 0.18s;
}

.win--closed {
  opacity: 0;
  visibility: hidden;
  transform: scale(0.94) translateY(10px);
  pointer-events: none;
}

.win__bar {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  height: 32px;
  padding-left: 12px;
  background: #eef1f7;
  border-bottom: 1px solid #e0e4ee;
  cursor: grab;
  touch-action: none;
}

.win__bar:active {
  cursor: grabbing;
}

.win__title {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 1;
  min-width: 0;
  font-size: 12.5px;
  font-weight: 500;
  white-space: nowrap;
}

.win__app {
  width: 14px;
  height: 14px;
  border-radius: 3px;
}

.win__app--notes {
  background: linear-gradient(180deg, #74b7ff 0%, #3b82f6 100%);
}

.win__app--music {
  background: linear-gradient(135deg, #ff7eb6 0%, #a855f7 100%);
}

.win__buttons {
  display: flex;
  height: 100%;
}

.win__buttons button {
  display: grid;
  place-items: center;
  width: 40px;
  height: 100%;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.win__buttons button:hover {
  background: rgba(0, 0, 0, 0.07);
}

.win__buttons .win__close:hover {
  background: #e81123;
}

.win__buttons .win__close:hover .glyph::before,
.win__buttons .win__close:hover .glyph::after {
  background: #fff;
}

.glyph {
  position: relative;
  width: 10px;
  height: 10px;
}

.glyph--min::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 5px;
  height: 1px;
  background: #1f2430;
}

.glyph--max {
  border: 1px solid #1f2430;
  border-radius: 1px;
}

.glyph--close::before,
.glyph--close::after {
  content: "";
  position: absolute;
  left: -2px;
  right: -2px;
  top: 4.5px;
  height: 1px;
  background: #1f2430;
  transform: rotate(45deg);
}

.glyph--close::after {
  transform: rotate(-45deg);
}

.win__body--notes {
  flex: 1;
  padding: 12px 16px;
  font-family: "Cascadia Mono", Consolas, ui-monospace, monospace;
  font-size: 13px;
  line-height: 1.75;
  color: #2a2f3a;
}

.win__body--notes strong {
  display: block;
  margin-bottom: 2px;
  font-family: "Be Vietnam Pro", "Segoe UI", sans-serif;
  font-size: 14px;
}

.win__body--music {
  display: flex;
  gap: 14px;
  flex: 1;
  align-items: center;
  padding: 14px;
}

.album {
  display: grid;
  place-items: center;
  flex-shrink: 0;
  width: 70px;
  height: 70px;
  border-radius: 10px;
  background: linear-gradient(135deg, #ff7eb6 0%, #a855f7 55%, #4f46e5 100%);
  color: rgba(255, 255, 255, 0.9);
  font-size: 30px;
  box-shadow: 0 6px 16px rgba(120, 60, 200, 0.35);
}

.track {
  display: flex;
  flex-direction: column;
  min-width: 0;
  flex: 1;
  font-size: 12.5px;
  color: #5b6475;
}

.track strong {
  overflow: hidden;
  color: #1f2430;
  font-size: 14px;
  white-space: nowrap;
  text-overflow: ellipsis;
}

.track__bar {
  height: 4px;
  margin: 10px 0 8px;
  overflow: hidden;
  border-radius: 4px;
  background: #e3e6ef;
}

.track__bar span {
  display: block;
  height: 100%;
  width: 0;
  border-radius: 4px;
  background: #a855f7;
  animation: track 40s linear infinite;
}

@keyframes track {
  to {
    width: 100%;
  }
}

.track__controls {
  display: flex;
  gap: 16px;
  color: #3b4252;
  font-size: 13px;
}

.track__play {
  color: #a855f7;
}

/* Taskbar ở đáy màn hình thu nhỏ: pet đứng trên mép trên của nó. */
.taskbar {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  display: flex;
  align-items: center;
  height: 44px;
  padding: 0 10px;
  background: rgba(20, 26, 44, 0.86);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.taskbar__apps {
  position: absolute;
  left: 50%;
  display: flex;
  gap: 4px;
  transform: translateX(-50%);
}

.tb {
  position: relative;
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border: 0;
  border-radius: 7px;
  background: transparent;
  color: inherit;
}

button.tb {
  cursor: pointer;
}

.tb:hover {
  background: rgba(255, 255, 255, 0.08);
}

.tb::before {
  content: "";
  width: 20px;
  height: 20px;
  border-radius: 5px;
}

.tb--start {
  grid-template-columns: 9px 9px;
  gap: 2px;
  place-content: center;
}

.tb--start::before {
  display: none;
}

.tb--start i {
  width: 9px;
  height: 9px;
  border-radius: 1.5px;
  background: linear-gradient(135deg, #4cc2ff 0%, #2b88d8 100%);
}

.tb--search::before {
  width: 13px;
  height: 13px;
  border: 2px solid #c9d4ee;
  border-radius: 50%;
  background: none;
  transform: translate(-1px, -1px);
  box-shadow: 5px 5px 0 -3.5px #c9d4ee;
}

.tb--files::before {
  height: 16px;
  border-radius: 3px;
  background: linear-gradient(180deg, #ffd66b 0%, #f4b400 100%);
}

.tb--browser::before {
  border-radius: 50%;
  background: conic-gradient(from 200deg, #2fbf71, #1a9bf0, #7c5cff, #2fbf71);
}

.tb--notes::before {
  background: linear-gradient(180deg, #74b7ff 0%, #3b82f6 100%);
}

.tb--music::before {
  background: linear-gradient(135deg, #ff7eb6 0%, #a855f7 100%);
}

/* Vạch dưới icon của cửa sổ đang mở. */
.tb--open::after {
  content: "";
  position: absolute;
  bottom: 1px;
  left: 50%;
  width: 6px;
  height: 3px;
  border-radius: 2px;
  background: #8fb3ff;
  transform: translateX(-50%);
}

.taskbar__tray {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-left: auto;
  color: #dbe3f6;
  font-size: 11.5px;
}

.tray__pet {
  image-rendering: pixelated;
}

.tray__icons {
  display: flex;
  gap: 8px;
}

.tray__icons svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: #dbe3f6;
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.clock {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  line-height: 1.3;
}

/* Lớp pet: chuột chỉ bắt ở pet, chỗ trống bấm xuống cửa sổ bên dưới. */
.desk__pets {
  position: absolute;
  inset: 0;
  z-index: 3;
  pointer-events: none;
}

.sprite {
  display: block;
  background-repeat: no-repeat;
}

.desk-pet {
  position: absolute;
  left: 0;
  top: 0;
  pointer-events: auto;
  cursor: grab;
  touch-action: none;
  border-radius: 14px;
  will-change: transform;
}

.desk-pet:active {
  cursor: grabbing;
}

.desk-pet:focus-visible {
  outline: 2px dashed rgba(156, 192, 255, 0.8);
  outline-offset: -8px;
}

/* Speech bubble giống trong app. */
.bubble {
  position: absolute;
  left: 0;
  top: 0;
  z-index: 4;
  width: max-content;
  max-width: 220px;
  padding: 5px 10px;
  border: 2px solid #2a2340;
  border-radius: 10px;
  background: #fffaf0;
  color: #2a2340;
  font: 600 13px/1.35 "Be Vietnam Pro", "Segoe UI", system-ui, sans-serif;
  white-space: pre-line;
  pointer-events: none;
  animation: bubble-in 0.15s ease-out;
}

.bubble::after {
  content: "";
  position: absolute;
  left: var(--tail, 50%);
  bottom: -7px;
  width: 10px;
  height: 10px;
  margin-left: -6px;
  border-right: 2px solid #2a2340;
  border-bottom: 2px solid #2a2340;
  background: #fffaf0;
  transform: rotate(45deg);
}

@keyframes bubble-in {
  from {
    opacity: 0;
    transform: translateY(4px);
  }
}

/* Chữ z bay lên lúc pet ngủ, sao quay quanh đầu lúc choáng. */
.zzz {
  position: absolute;
  left: 0;
  top: 0;
  z-index: 4;
  color: #cfe0ff;
  font: 800 13px/1 "Be Vietnam Pro", sans-serif;
  pointer-events: none;
}

.zzz span {
  position: absolute;
  opacity: 0;
  animation: zzz 2.4s ease-out infinite;
}

.zzz span:nth-child(2) {
  animation-delay: 0.8s;
  font-size: 11px;
}

.zzz span:nth-child(3) {
  animation-delay: 1.6s;
  font-size: 9px;
}

@keyframes zzz {
  0% {
    opacity: 0;
    transform: translate(0, 0);
  }
  20% {
    opacity: 1;
  }
  100% {
    opacity: 0;
    transform: translate(14px, -26px);
  }
}

.stars {
  position: absolute;
  left: 0;
  top: 0;
  z-index: 4;
  pointer-events: none;
}

.stars-orbit {
  position: absolute;
  width: 0;
  height: 0;
  animation: orbit 0.9s linear infinite;
}

.stars-orbit span {
  position: absolute;
  color: var(--warm);
  font-size: 15px;
  line-height: 1;
  text-shadow: 0 0 6px rgba(255, 204, 98, 0.8);
}

@keyframes orbit {
  to {
    transform: rotate(360deg);
  }
}

/* Các mục bên dưới. */
.section {
  max-width: 1160px;
  margin: 0 auto;
  padding: 96px var(--gutter) 0;
}

.section__head {
  max-width: 680px;
}

.section__head h2 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 800;
  text-wrap: balance;
}

.section__head .lede {
  margin-top: 14px;
  color: var(--text-2);
  font-size: 1.07rem;
}

.section--split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
  gap: 48px;
  align-items: center;
}

.features {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin: 40px 0 0;
  padding: 0;
  list-style: none;
}

.feature {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.04);
}

.feature h3 {
  margin: 16px 0 8px;
  font-size: 1.12rem;
  font-weight: 700;
}

.feature p {
  color: var(--text-2);
  font-size: 15px;
}

.feature__icon,
.calm__icon {
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border-radius: 14px;
  background: rgba(79, 134, 255, 0.14);
  color: var(--accent-2);
}

.feature__icon .icon,
.calm__icon .icon {
  width: 24px;
  height: 24px;
}

.feature--hand .feature__icon,
.feature--heart .feature__icon {
  background: rgba(255, 159, 189, 0.14);
  color: var(--pink);
}

.feature--moon .feature__icon,
.feature--clock .feature__icon {
  background: rgba(255, 204, 98, 0.14);
  color: var(--warm);
}

.feature--calendar .feature__icon,
.feature--group .feature__icon {
  background: rgba(134, 200, 164, 0.15);
  color: var(--grass);
}

.secret {
  margin-top: 26px;
  color: var(--muted);
  font-size: 15px;
  text-align: center;
}

/* Demo thời tiết: cảnh nhỏ có một con pet, đổi màu trời theo kiểu thời tiết. */
.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 22px;
}

.chips + .chips {
  margin-top: 10px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 40px;
  padding: 0 14px;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-2);
  font: inherit;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition:
    background 0.15s,
    border-color 0.15s;
}

.chip:hover {
  background: rgba(255, 255, 255, 0.08);
}

.chip[aria-pressed="true"] {
  border-color: var(--accent);
  background: #23407a;
  color: #fff;
  box-shadow: 0 0 18px rgba(79, 134, 255, 0.3);
}

.chip--hot[aria-pressed="true"] {
  border-color: #ff8a4c;
  background: #6a3220;
  box-shadow: 0 0 18px rgba(255, 122, 48, 0.3);
}

.chip--cold[aria-pressed="true"] {
  border-color: #6cc4ff;
  background: #1d4a6e;
}

.chip__icon {
  display: flex;
  width: 17px;
  height: 17px;
}

.chip__icon svg {
  width: 100%;
  height: 100%;
  overflow: visible;
}

.note {
  margin-top: 20px;
  color: var(--muted);
  font-size: 14px;
}

.demo {
  padding: 10px;
  border: 1px solid #2b3b5e;
  border-radius: 24px;
  background: linear-gradient(180deg, #121c33 0%, #0b1222 100%);
  box-shadow: 0 30px 70px rgba(0, 0, 0, 0.45);
}

.demo__stage {
  position: relative;
  height: 340px;
  overflow: hidden;
  border-radius: 16px;
  background: linear-gradient(180deg, #1a2f5e 0%, #13254b 60%, #0f1d3c 100%);
  transition: background 0.6s;
}

.demo__stage[data-sky="sunny"],
.demo__stage[data-sky="petals"] {
  background: linear-gradient(180deg, #3d78c9 0%, #5a96d8 55%, #8bb8e2 100%);
}

.demo__stage[data-sky="cloudy"],
.demo__stage[data-sky="fog"] {
  background: linear-gradient(180deg, #3a4a6e 0%, #4b5d82 60%, #63749a 100%);
}

.demo__stage[data-sky="rain"],
.demo__stage[data-sky="storm"] {
  background: linear-gradient(180deg, #1b2a48 0%, #24375c 60%, #2d4269 100%);
}

.demo__stage[data-sky="snow"] {
  background: linear-gradient(180deg, #2a3f69 0%, #3e5684 60%, #5671a0 100%);
}

.demo__stage--flash::after {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(255, 255, 240, 0.35);
  animation: flash 0.25s ease-out forwards;
  pointer-events: none;
}

@keyframes flash {
  to {
    opacity: 0;
  }
}

.demo__stars {
  position: absolute;
  inset: 0 0 40% 0;
  opacity: 0;
  transition: opacity 0.6s;
  background-image:
    radial-gradient(1.4px 1.4px at 12% 20%, #eef2ff 99%, transparent),
    radial-gradient(1.2px 1.2px at 28% 42%, #eef2ff 99%, transparent),
    radial-gradient(1.6px 1.6px at 46% 14%, #eef2ff 99%, transparent),
    radial-gradient(1.2px 1.2px at 64% 34%, #eef2ff 99%, transparent),
    radial-gradient(1.5px 1.5px at 82% 18%, #eef2ff 99%, transparent),
    radial-gradient(1.1px 1.1px at 90% 46%, #eef2ff 99%, transparent),
    radial-gradient(1.3px 1.3px at 6% 52%, #eef2ff 99%, transparent);
}

.demo__stage[data-sky="clear"] .demo__stars,
.demo__stage[data-sky="rain"] .demo__stars,
.demo__stage[data-sky="snow"] .demo__stars {
  opacity: 0.7;
}

.demo__stage[data-sky="clear"] .demo__stars {
  opacity: 1;
}

.demo__hills {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 40px;
  width: 100%;
  height: 90px;
}

.demo__ground {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 44px;
  background: linear-gradient(180deg, #2c5a52 0%, #1d3a3d 100%);
  border-top: 2px solid #86c8a4;
}

.demo-pet {
  position: absolute;
  left: 0;
  top: 0;
  will-change: transform;
}

.demo .weather {
  position: absolute;
  left: 0;
  top: 0;
  pointer-events: none;
}

.demo .bubble {
  z-index: 5;
}

/* Nhãn nhiệt độ cạnh pet, như trong app. */
.temperature {
  position: absolute;
  left: 0;
  top: 0;
  z-index: 4;
  display: flex;
  align-items: center;
  gap: 3px;
  padding: 1px 7px 1px 4px;
  border: 2px solid #2a2340;
  border-radius: 9px;
  background: #fffaf0;
  color: #2a2340;
  font: 700 11px/1.35 "Be Vietnam Pro", "Segoe UI", sans-serif;
  white-space: nowrap;
  pointer-events: none;
  box-shadow: 0 2px 0 rgba(42, 35, 64, 0.35);
}

.temperature[data-warmth="hot"] {
  color: #d9480f;
}

.temperature[data-warmth="cold"] {
  color: #1c64d8;
}

.temperature svg {
  width: 13px;
  height: 13px;
  overflow: visible;
}

/* Bảng nhân vật. */
.roster {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(168px, 1fr));
  gap: 14px;
  margin: 40px 0 0;
  padding: 0;
  list-style: none;
}

.pet-card {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
  height: 100%;
  padding: 10px 12px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  color: var(--text);
  font: inherit;
  text-align: center;
  cursor: pointer;
  transition:
    border-color 0.15s,
    transform 0.15s,
    background 0.15s;
}

.pet-card:hover {
  border-color: var(--line-2);
  background: rgba(30, 48, 90, 0.7);
  transform: translateY(-2px);
}

.pet-card[aria-pressed="true"] {
  border-color: var(--accent);
  box-shadow: 0 0 22px rgba(79, 134, 255, 0.22);
}

.pet-card__stage {
  position: relative;
  display: grid;
  place-items: end center;
  width: 100%;
  height: 120px;
}

.pet-card__stage::before {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 10px;
  width: 92px;
  height: 14px;
  border-radius: 50%;
  background: radial-gradient(closest-side, rgba(134, 200, 164, 0.35), transparent);
  transform: translateX(-50%);
}

.sprite--card {
  position: relative;
  width: 120px;
  height: 120px;
  background-size: 480px 120px;
  animation: strip 0.8s steps(4) infinite;
}

.pet-card:hover .sprite--card,
.pet-card:focus-visible .sprite--card {
  animation-duration: 0.5s;
}

@keyframes strip {
  to {
    background-position: -480px 0;
  }
}

.pet-card__name {
  margin-top: 4px;
  font-size: 17px;
  font-weight: 700;
}

.pet-card__about {
  margin-top: 4px;
  color: var(--muted);
  font-size: 13.5px;
  line-height: 1.45;
}

.pet-card__badge {
  position: absolute;
  top: 10px;
  right: 10px;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-size: 11.5px;
  font-weight: 600;
  opacity: 0;
  transition: opacity 0.15s;
}

.pet-card[aria-pressed="true"] .pet-card__badge {
  opacity: 1;
}

/* Cách chơi. */
.tips {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 36px 0 0;
}

.tip {
  display: grid;
  grid-template-columns: minmax(0, 190px) minmax(0, 1fr);
  gap: 16px;
  align-items: center;
  padding: 12px 16px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
}

.tip dt {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
}

.tip dd {
  margin: 0;
  color: var(--text-2);
  font-size: 15px;
}

kbd {
  display: inline-block;
  padding: 3px 10px;
  border: 1px solid #34497a;
  border-bottom-width: 3px;
  border-radius: 8px;
  background: #1b2a4a;
  color: var(--text);
  font: 600 13.5px/1.5 "Be Vietnam Pro", sans-serif;
  white-space: nowrap;
}

.tip__join {
  color: var(--muted);
  font-size: 14px;
}

/* Nhẹ nhàng, không làm phiền. */
.calm {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 26px 32px;
  margin: 36px 0 0;
  padding: 0;
  list-style: none;
}

.calm__item {
  display: flex;
  gap: 16px;
}

.calm__item h3 {
  margin-bottom: 6px;
  font-size: 1.05rem;
  font-weight: 700;
}

.calm__item p {
  color: var(--text-2);
  font-size: 15px;
}

.calm__icon {
  flex-shrink: 0;
  background: rgba(127, 216, 190, 0.13);
  color: #7fd8be;
}

/* Tải về. */
.download {
  position: relative;
  max-width: 820px;
  margin: 0 auto;
  padding: 48px 36px 40px;
  overflow: hidden;
  border: 1px solid #3f5f9f;
  border-radius: 28px;
  background:
    radial-gradient(80% 60% at 50% 0%, rgba(79, 134, 255, 0.28) 0%, transparent 70%),
    linear-gradient(180deg, rgba(36, 60, 112, 0.85) 0%, rgba(17, 29, 58, 0.92) 100%);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.45);
  text-align: center;
}

.download__logo {
  display: block;
  margin: 0 auto 14px;
  filter: drop-shadow(0 8px 20px rgba(0, 0, 0, 0.4));
}

.download h2 {
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  font-weight: 800;
}

.download .lede {
  margin: 10px 0 26px;
  color: var(--text-2);
}

.download__meta {
  margin-top: 14px;
  color: var(--muted);
  font-size: 14px;
}

.steps {
  max-width: 600px;
  margin: 30px auto 0;
  padding: 0;
  list-style: none;
  counter-reset: step;
  text-align: left;
}

.steps li {
  position: relative;
  padding: 0 0 14px 44px;
  color: var(--text-2);
  font-size: 15px;
  counter-increment: step;
}

.steps li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: -2px;
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: rgba(79, 134, 255, 0.2);
  color: var(--accent-2);
  font-weight: 700;
  font-size: 14px;
}

.download__note {
  margin-top: 10px;
  color: var(--muted);
  font-size: 14px;
}

/* Chân trang: một con ngủ trên bãi cỏ. */
.footer {
  position: relative;
  margin-top: 110px;
}

.footer__ground {
  position: relative;
  height: 90px;
  background: linear-gradient(180deg, transparent 0%, transparent 60%, #173233 60%, #10202a 100%);
}

.footer__ground::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 54px;
  height: 2px;
  background: rgba(134, 200, 164, 0.7);
}

.sprite--sleep {
  position: absolute;
  left: 50%;
  /* Chân (anchor, 60/64 của frame) chạm vạch cỏ ở 54px. */
  top: -6px;
  width: 64px;
  height: 64px;
  margin-left: -32px;
  background-image: url(/pets/a-momo/sleep.webp);
  background-size: 256px 64px;
  animation: strip-small 1.33s steps(4) infinite;
}

@keyframes strip-small {
  to {
    background-position: -256px 0;
  }
}

.footer__z {
  position: absolute;
  left: calc(50% + 18px);
  top: 14px;
  color: #cfe0ff;
  font-weight: 800;
  font-size: 13px;
  animation: zzz 2.4s ease-out infinite;
}

.footer__inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px;
  padding: 18px max(var(--gutter), calc((100% - 1120px) / 2)) 26px;
  background: #10202a;
  color: var(--muted);
  font-size: 14px;
}

.footer__inner a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--text-2);
  text-decoration: none;
}

.footer__inner a:hover {
  color: var(--text);
}

@media (max-width: 960px) {
  .features,
  .calm {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .section--split {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
  }

  .tips {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 720px) {
  :root {
    --gutter: 16px;
  }

  .nav__links {
    display: none;
  }

  .nav__lang {
    margin-left: auto;
  }

  .hero {
    padding-top: 40px;
  }

  .desk {
    margin-top: 32px;
    padding: 6px;
    border-radius: 18px;
  }

  .desk__screen {
    border-radius: 12px;
  }

  .features,
  .calm {
    grid-template-columns: minmax(0, 1fr);
  }

  .section {
    padding-top: 72px;
  }

  .roster {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
  }

  .sprite--card {
    width: 96px;
    height: 96px;
    background-size: 384px 96px;
    animation-name: strip-card-small;
  }

  .pet-card__stage {
    height: 98px;
  }

  .tip {
    grid-template-columns: minmax(0, 1fr);
    gap: 8px;
  }

  .download {
    padding: 36px 18px 30px;
    border-radius: 22px;
  }

  .demo__stage {
    height: 300px;
  }
}

/* Điện thoại hẹp: nút Tải về đã có ngay ở đầu trang, bỏ khỏi thanh trên cho vừa. */
@media (max-width: 480px) {
  .nav .btn--small {
    display: none;
  }

  .nav__lang {
    padding-right: 0;
  }
}

@keyframes strip-card-small {
  to {
    background-position: -384px 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .star,
  .sprite--card,
  .sprite--sleep,
  .footer__z,
  .zzz span,
  .stars-orbit,
  .track__bar span {
    animation: none;
  }

  .btn,
  .pet-card {
    transition: none;
  }
}