:root {
  --bg0: #070305;
  --bg1: #0b0507;
  --panel: rgba(255, 255, 255, 0.06);
  --panel2: rgba(255, 255, 255, 0.04);
  --stroke: rgba(255, 255, 255, 0.11);
  --text: rgba(255, 255, 255, 0.92);
  --muted: rgba(255, 255, 255, 0.72);
  --muted2: rgba(255, 255, 255, 0.58);
  --accent: #ffcc3a;
  --accent2: #ff4d4d;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.55);
  --radius: 18px;
  --radius-sm: 14px;
  --container: 1120px;
  --font: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial,
    "Apple Color Emoji", "Segoe UI Emoji";
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: 
    radial-gradient(circle at 10% 20%, rgba(255, 204, 58, 0.1), transparent 40%),
    radial-gradient(circle at 90% 10%, rgba(255, 77, 77, 0.15), transparent 40%),
    radial-gradient(circle at 50% -20%, #750d0d, #0b0507 80%);
  background-attachment: fixed;
}

a {
  color: inherit;
}

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono",
    "Courier New", monospace;
  font-size: 0.95em;
}

.container {
  width: min(var(--container), calc(100vw - 32px));
  margin: 0 auto;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 12px;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid var(--stroke);
  background: rgba(9, 4, 6, 0.95);
  color: var(--text);
  text-decoration: none;
  z-index: 999;
}

.skip-link:focus {
  left: 12px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: rgba(9, 4, 6, 0.72);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 12px 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  min-width: max-content;
}

.brand-badge {
  width: 12px;
  height: 12px;
  border-radius: 999px;
  background: radial-gradient(circle at 30% 30%, #fff4b5, var(--accent) 40%, var(--accent2) 95%);
  box-shadow: 0 0 0 5px rgba(255, 204, 58, 0.12);
}

.brand-name {
  font-weight: 800;
  letter-spacing: 0.2px;
}

.site-nav {
  display: flex;
  gap: 8px;
  align-items: center;
}

.site-nav a {
  text-decoration: none;
  color: var(--muted);
  font-weight: 700;
  font-size: 14px;
  padding: 10px 12px;
  border-radius: 999px;
}

.site-nav a:hover {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text);
}

.header-cta {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 999px;
  border: 1px solid var(--stroke);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  font-weight: 800;
  cursor: pointer;
}

.nav-toggle:hover {
  background: rgba(255, 255, 255, 0.06);
}

.nav-toggle-icon {
  width: 14px;
  height: 14px;
  display: inline-block;
  border-top: 2px solid rgba(255, 255, 255, 0.75);
  border-bottom: 2px solid rgba(255, 255, 255, 0.75);
  position: relative;
}

.nav-toggle-icon::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: calc(50% - 1px);
  height: 2px;
  background: rgba(255, 255, 255, 0.75);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  text-decoration: none;
  border-radius: 999px;
  border: 1px solid var(--stroke);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  font-weight: 850;
  letter-spacing: 0.1px;
  padding: 12px 16px;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), background 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.btn:hover {
  transform: translateY(-4px) scale(1.02);
  background: rgba(255, 255, 255, 0.1);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.3);
}

.btn:active {
  transform: translateY(-1px) scale(0.98);
  box-shadow: 0 5px 10px rgba(0, 0, 0, 0.2);
}

.btn-sub {
  font-size: 12px;
  font-weight: 900;
  padding: 2px 8px;
  border-radius: 999px;
  background: rgba(0, 0, 0, 0.25);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: var(--muted);
}

.btn-primary {
  border-color: rgba(255, 204, 58, 0.33);
  background: linear-gradient(180deg, rgba(255, 204, 58, 0.18), rgba(255, 77, 77, 0.08));
  box-shadow: 0 14px 30px rgba(0, 0, 0, 0.35);
  animation: btn-glow 3s infinite;
}

.btn-primary:hover {
  border-color: #ffcc3a;
  background: linear-gradient(180deg, rgba(255, 204, 58, 0.25), rgba(255, 77, 77, 0.15));
}

@keyframes btn-glow {
  0%, 100% { box-shadow: 0 14px 30px rgba(0, 0, 0, 0.35); border-color: rgba(255, 204, 58, 0.33); }
  50% { box-shadow: 0 0 25px rgba(255, 204, 58, 0.5); border-color: rgba(255, 204, 58, 0.9); }
}

.btn-ghost {
  background: transparent;
}

.btn-sm {
  padding: 10px 12px;
  font-size: 14px;
}

.btn-lg {
  padding: 14px 18px;
  font-size: 15px;
}

.btn-xl {
  padding: 16px 20px;
  font-size: 16px;
}

.hero {
  padding: 64px 0 36px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 34px;
  align-items: center;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--accent);
  font-weight: 900;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-size: 12px;
}

h1 {
  margin: 0 0 12px;
  font-size: clamp(36px, 4.2vw, 54px);
  line-height: 1.06;
  letter-spacing: -0.03em;
}

.lead {
  margin: 0 0 18px;
  font-size: 18px;
  line-height: 1.65;
  color: var(--muted);
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 18px 0 18px;
}

.meta {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin: 18px 0 12px;
}

.meta-item {
  margin: 0;
  padding: 12px 14px;
  border: 1px solid var(--stroke);
  background: rgba(255, 255, 255, 0.04);
  border-radius: 14px;
}

.meta-item dt {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted2);
}

.meta-item dd {
  margin: 6px 0 0;
  font-weight: 850;
}

.note {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.55;
  color: var(--muted2);
}

.note code,
.download-note code {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 2px 6px;
  border-radius: 8px;
}

.media-card {
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.07), rgba(255, 255, 255, 0.03));
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: var(--shadow);
  padding: 14px;
}

.app-shot {
  width: 100%;
  height: auto;
  display: block;
  border-radius: calc(var(--radius) - 10px);
  border: 1px solid rgba(0, 0, 0, 0.35);
}

.media-caption {
  margin: 10px 0 0;
  color: var(--muted2);
  font-size: 13px;
  text-align: center;
}

.section {
  padding: 48px 0;
}

.section-alt {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.04), rgba(255, 255, 255, 0));
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.section-title {
  margin: 0;
  font-size: clamp(24px, 2.6vw, 34px);
  letter-spacing: -0.02em;
}

.section-lead {
  margin: 10px 0 0;
  color: var(--muted);
  max-width: 72ch;
  line-height: 1.65;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin-top: 22px;
}

.card {
  padding: 16px 16px 14px;
  border: 1px solid var(--stroke);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.04);
}

.card-icon {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  background: rgba(255, 204, 58, 0.12);
  border: 1px solid rgba(255, 204, 58, 0.22);
  color: var(--accent);
  margin-bottom: 12px;
}

.card-icon svg {
  width: 24px;
  height: 24px;
}

.card h3 {
  margin: 0 0 8px;
  font-size: 16px;
  letter-spacing: -0.01em;
}

.card p {
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
}

.steps {
  list-style: none;
  padding: 0;
  margin: 20px 0 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  counter-reset: step;
}

.step {
  position: relative;
  padding: 16px 16px 14px;
  border: 1px solid var(--stroke);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.04);
}

.step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  top: 14px;
  right: 14px;
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 999px;
  background: rgba(255, 77, 77, 0.1);
  border: 1px solid rgba(255, 77, 77, 0.2);
  color: rgba(255, 180, 180, 0.92);
  font-weight: 900;
}

.step h3 {
  margin: 0 0 8px;
  font-size: 16px;
  letter-spacing: -0.01em;
}

.step p {
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
}

.download-card {
  margin-top: 14px;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 18px;
  border-radius: var(--radius);
  padding: 18px;
  border: 1px solid rgba(255, 204, 58, 0.25);
  background: linear-gradient(180deg, rgba(255, 204, 58, 0.08), rgba(255, 255, 255, 0.03));
  box-shadow: var(--shadow);
}

.download-meta {
  margin: 14px 0 0;
  padding: 0;
  list-style: none;
  color: var(--muted);
  display: grid;
  gap: 6px;
}

.download-meta strong {
  color: var(--text);
}

.pill {
  display: inline-block;
  padding: 8px 12px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(0, 0, 0, 0.2);
  font-weight: 900;
  letter-spacing: 0.02em;
}

.download-note {
  margin: 12px 0 0;
  color: var(--muted);
  line-height: 1.6;
}

.faq {
  margin-top: 18px;
  display: grid;
  gap: 10px;
}

details {
  border: 1px solid var(--stroke);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.04);
  padding: 12px 14px;
}

summary {
  cursor: pointer;
  font-weight: 900;
  list-style: none;
}

summary::-webkit-details-marker {
  display: none;
}

details[open] {
  background: rgba(255, 255, 255, 0.05);
}

details p {
  margin: 10px 0 0;
  color: var(--muted);
  line-height: 1.6;
}

.site-footer {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(9, 4, 6, 0.6);
}

.footer-row {
  padding: 18px 0;
  display: grid;
  gap: 8px;
}

.footer-left,
.footer-right {
  margin: 0;
  color: var(--muted2);
  line-height: 1.55;
}

.toast {
  position: fixed;
  bottom: 18px;
  left: 50%;
  transform: translate(-50%, 20px);
  opacity: 0;
  pointer-events: none;
  background: rgba(16, 7, 10, 0.92);
  border: 1px solid rgba(255, 255, 255, 0.14);
  padding: 12px 14px;
  border-radius: 14px;
  box-shadow: var(--shadow);
  color: var(--text);
  width: min(720px, calc(100vw - 24px));
  text-align: center;
  transition: opacity 0.22s ease, transform 0.22s ease;
}

.toast.show {
  opacity: 1;
  transform: translate(-50%, 0);
}

.admin-cta {
  padding: 38px 0 32px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.04), rgba(255, 255, 255, 0.02));
}

.admin-cta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.admin-cta h3 {
  margin: 8px 0 4px;
  font-size: 22px;
}

.muted {
  color: var(--muted);
}

.small {
  font-size: 13px;
}

.modal {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  z-index: 120;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(4px);
}

.modal-backdrop {
  position: absolute;
  inset: 0;
}

.modal[hidden] {
  display: none;
}

.modal-card {
  position: relative;
  width: min(720px, calc(100vw - 32px));
  background: rgba(12, 6, 8, 0.96);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 16px;
  padding: 18px 18px 16px;
  box-shadow: var(--shadow);
}

.modal-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
}

.icon-btn {
  border: 1px solid var(--stroke);
  background: rgba(255, 255, 255, 0.05);
  color: var(--text);
  border-radius: 10px;
  width: 38px;
  height: 38px;
  font-size: 18px;
  cursor: pointer;
}

.google-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
  flex-wrap: wrap;
}

.admin-form {
  display: grid;
  gap: 12px;
  margin: 12px 0;
}

.admin-form.locked {
  opacity: 0.6;
  pointer-events: none;
}

.field {
  display: grid;
  gap: 6px;
}

.field input {
  width: 100%;
  padding: 12px 12px;
  border-radius: 10px;
  border: 1px solid var(--stroke);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
}

.field span {
  font-weight: 700;
  color: var(--muted2);
}

.file-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 10px;
}

.file-label {
  position: relative;
  overflow: hidden;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
  border: 1px dashed rgba(255, 255, 255, 0.2);
  border-radius: 12px;
  color: var(--muted);
  cursor: pointer;
  background: rgba(255, 255, 255, 0.03);
}

.file-label input {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
}

.modal-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.pill.ghost {
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.18);
  color: var(--muted);
}

.modal-open {
  overflow: hidden;
}

@media (max-width: 980px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 18px;
  }

  .meta {
    grid-template-columns: 1fr;
  }

  .card-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .steps {
    grid-template-columns: 1fr;
  }

  .download-card {
    grid-template-columns: 1fr;
  }

  .admin-cta-row {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 820px) {
  .site-nav {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .header-cta {
    display: none;
  }

  .header-row {
    position: relative;
  }

  body.nav-open .site-nav {
    display: flex;
    position: absolute;
    top: 58px;
    left: 0;
    right: 0;
    padding: 12px;
    gap: 6px;
    flex-direction: column;
    background: rgba(9, 4, 6, 0.95);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
  }

  body.nav-open .site-nav a {
    width: 100%;
  }
}

@media (max-width: 640px) {
  .container {
    width: min(var(--container), calc(100vw - 24px));
  }

  .card-grid {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  .btn,
  .toast {
    transition: none;
  }

  .btn:hover {
    transform: none;
  }
}

/* Tet 2026 Loader */
.page-loader {
  position: fixed;
  inset: 0;
  background: radial-gradient(circle at center, #8a1c1c, #0b0507);
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity 0.6s ease, visibility 0.6s ease;
}

.page-loader.hidden {
  opacity: 0;
  visibility: hidden;
}

.loader-content {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  /* Đảm bảo click xuyên qua nội dung để kích hoạt pháo hoa */
  pointer-events: none;
}

.loader-content > * {
  pointer-events: none;
  user-select: none;
}

.horse-logo {
  width: 80px;
  height: 80px;
  filter: drop-shadow(0 0 15px rgba(255, 204, 58, 0.6));
  animation: float-horse 3s ease-in-out infinite;
}

.loading-text {
  color: #ffcc3a;
  font-weight: 900;
  letter-spacing: 2px;
  text-transform: uppercase;
  font-size: 14px;
  margin: 0;
  background: rgba(0, 0, 0, 0.25);
  padding: 10px 20px;
  border-radius: 99px;
  backdrop-filter: blur(3px);
  animation: pulse 1.5s infinite;
}

@keyframes float-horse {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

.blossom-container {
  position: fixed;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 10001;
}

.blossom {
  position: absolute;
  color: #ffdf7e;
  animation: fall linear infinite;
}

@keyframes fall {
  from { transform: translateY(-10vh) rotate(0deg); }
  to { transform: translateY(110vh) translateX(var(--sway, 0)) rotate(720deg); opacity: 0; }
}

/* Interactive Blossom (Hoa rơi theo chuột) */
.interactive-blossom {
  position: fixed;
  pointer-events: none;
  z-index: 10001;
  animation: fall-interactive 1s linear forwards;
}

@keyframes fall-interactive {
  to { transform: translateY(100px) rotate(180deg); opacity: 0; }
}

/* Firework Particles (Pháo hoa) */
.firework-particle {
  position: fixed;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  pointer-events: none;
  z-index: 10002;
  animation: explode 0.8s cubic-bezier(0.25, 1, 0.5, 1) forwards;
}

@keyframes explode {
  0% { transform: translate(0, 0) scale(1); opacity: 1; }
  100% { transform: translate(var(--tx), var(--ty)) scale(0); opacity: 0; }
}

/* Music Toggle Button */
.music-btn {
  position: fixed;
  bottom: 20px;
  left: 20px;
  z-index: 900;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: rgba(255, 204, 58, 0.15);
  border: 1px solid rgba(255, 204, 58, 0.4);
  color: #ffcc3a;
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: all 0.3s ease;
  backdrop-filter: blur(4px);
}

.music-btn:hover {
  background: rgba(255, 204, 58, 0.3);
  transform: scale(1.1);
}

.music-btn svg {
  width: 20px;
  height: 20px;
  position: absolute;
}

.music-btn .icon-off { opacity: 0; transition: opacity 0.3s; }
.music-btn.muted .icon-off { opacity: 1; }
.music-btn.muted .icon-music { opacity: 0.5; }
.music-btn:not(.muted) { animation: spin-slow 8s linear infinite; }

@keyframes spin-slow {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* Visualizer Effect (Sóng nhạc) */
.music-btn::before,
.music-btn::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 1px solid rgba(255, 204, 58, 0.6);
  opacity: 0;
  z-index: -1;
  pointer-events: none;
}

.music-btn:not(.muted)::before { animation: ripple 2s linear infinite; }
.music-btn:not(.muted)::after { animation: ripple 2s linear 1s infinite; }

@keyframes ripple {
  0% { transform: scale(1); opacity: 0.8; border-width: 2px; }
  100% { transform: scale(2.2); opacity: 0; border-width: 0; }
}