/* ============================================================
   Tokens
   ============================================================ */
:root {
  /* Avatar-derived base */
  --cream: #f5ebdd;
  --teal: #4fb6a8;
  --teal-dark: #2e8c80;
  --rust-orange: #e8703a;

  /* Gemini / air accents */
  --sky-blue: #a8d8f0;
  --lavender: #c9b6e4;
  --soft-yellow: #fce38a;

  /* Fire / Sơn Đầu Hỏa accents */
  --flame-orange: #ff8c42;
  --flame-gold: #ffc857;
  --flame-red: #e8553a;

  /* Neutrals */
  --text-dark: #4a3f35;
  --white-soft: #fffdf8;

  --font-heading: "Baloo 2", "Quicksand", sans-serif;
  --font-body: "Quicksand", sans-serif;

  --radius: 22px;
  --shadow-soft: 0 12px 32px rgba(74, 63, 53, 0.12);
}

/* ============================================================
   Reset & base
   ============================================================ */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  color: var(--text-dark);
  background: linear-gradient(
    180deg,
    var(--sky-blue) 0%,
    var(--lavender) 22%,
    var(--cream) 55%,
    var(--cream) 100%
  );
  min-height: 100vh;
  overflow-x: hidden;
}

body.is-locked {
  overflow: hidden;
  height: 100vh;
}

h1, h2, h3 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.25;
}

.highlight {
  background: linear-gradient(120deg, var(--flame-orange), var(--flame-red));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

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

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
}

/* ============================================================
   Twinkling star field
   ============================================================ */
.stars {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.star {
  position: absolute;
  border-radius: 50%;
  background: var(--white-soft);
  opacity: 0.6;
  animation: twinkle 3s ease-in-out infinite;
}

@keyframes twinkle {
  0%, 100% { opacity: 0.15; transform: scale(0.8); }
  50% { opacity: 0.9; transform: scale(1.2); }
}

/* ============================================================
   Music mute toggle
   ============================================================ */
.btn-mute {
  position: fixed;
  top: 1rem;
  right: 1rem;
  z-index: 110;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  border-radius: 50%;
  background: rgba(255, 253, 248, 0.85);
  box-shadow: var(--shadow-soft);
  backdrop-filter: blur(4px);
  transition: transform 0.2s ease, opacity 0.4s ease;
  opacity: 0;
}

.btn-mute.is-visible {
  opacity: 1;
}

.btn-mute:hover,
.btn-mute:focus-visible {
  transform: scale(1.08);
}

/* ============================================================
   Cover / "Open your gift" screen
   ============================================================ */
.cover {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  background: radial-gradient(circle at 50% 30%, #4a3f86 0%, #2b1f5c 45%, #140f33 100%);
  transition: opacity 0.6s ease, visibility 0.6s ease;
}

.cover.is-open {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.cover__content {
  padding: 2rem;
  max-width: 28rem;
}

.gem-journey {
  position: relative;
  width: 170px;
  height: 170px;
  margin: 0 auto 1.5rem;
}

.gem-journey__earth {
  position: absolute;
  bottom: 2px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 3rem;
  filter: drop-shadow(0 0 14px rgba(168, 216, 240, 0.4));
  animation: earth-glow 3s ease-in-out infinite;
}

@keyframes earth-glow {
  0%, 100% { filter: drop-shadow(0 0 12px rgba(168, 216, 240, 0.4)); }
  50% { filter: drop-shadow(0 0 24px rgba(168, 216, 240, 0.7)); }
}

.gem-journey__gem,
.gem-journey__spark {
  position: absolute;
  top: 0;
  left: 86%;
  animation: gem-fly 4s ease-in infinite;
}

.gem-journey__gem {
  font-size: 2.1rem;
  filter: drop-shadow(0 0 12px rgba(255, 140, 66, 0.9));
}

.gem-journey__spark {
  font-size: 1.1rem;
  opacity: 0;
}

.gem-journey__spark--1 {
  animation-delay: 0.15s;
}

.gem-journey__spark--2 {
  animation-delay: 0.32s;
}

.gem-journey__spark--3 {
  animation-delay: 0.5s;
}

@keyframes gem-fly {
  0% { top: 0%; left: 86%; transform: scale(0.6) rotate(-20deg); opacity: 0; }
  18% { opacity: 1; transform: scale(1) rotate(-5deg); }
  55% { top: 45%; left: 46%; transform: scale(1.05) rotate(8deg); opacity: 1; }
  85% { top: 62%; left: 50%; transform: scale(0.7) rotate(0deg); opacity: 0.6; }
  100% { top: 64%; left: 50%; transform: scale(0.3) rotate(0deg); opacity: 0; }
}

.gem-journey__number {
  position: absolute;
  top: 38%;
  left: 58%;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.2rem;
  background: linear-gradient(120deg, var(--flame-gold), var(--flame-red));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 0 12px rgba(255, 140, 66, 0.5);
  opacity: 0;
  animation: number-flicker 4s ease-in infinite;
}

@keyframes number-flicker {
  0%, 30% { opacity: 0; transform: scale(0.7); }
  45% { opacity: 1; transform: scale(1.1); }
  60% { opacity: 0.8; transform: scale(1); }
  75%, 100% { opacity: 0; transform: scale(0.8); }
}

.cover__title {
  margin-top: 1.25rem;
  font-size: clamp(1.6rem, 6vw, 2.4rem);
  color: var(--white-soft);
}

.reveal-word {
  display: inline-block;
  opacity: 0;
  filter: blur(4px);
  animation: word-reveal 0.6s ease forwards;
  animation-delay: calc(0.25s + var(--i) * 0.18s);
}

.reveal-word--highlight {
  background: linear-gradient(120deg, var(--flame-orange), var(--flame-red));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

@keyframes word-reveal {
  to { opacity: 1; filter: blur(0); }
}

.cover__code {
  margin-top: 1rem;
  font-family: monospace;
  font-size: 0.85rem;
  letter-spacing: 0.2em;
  color: var(--lavender);
  opacity: 0.7;
}

.btn-open {
  margin-top: 2rem;
  padding: 0.9rem 2.4rem;
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--white-soft);
  background: linear-gradient(120deg, var(--flame-orange), var(--flame-red));
  border-radius: 999px;
  box-shadow: var(--shadow-soft);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  animation: pulse 2.4s ease-in-out infinite;
}

.btn-open:hover,
.btn-open:focus-visible {
  transform: translateY(-3px) scale(1.04);
  box-shadow: 0 16px 36px rgba(232, 85, 58, 0.35);
}

@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(232, 85, 58, 0.35); }
  50% { box-shadow: 0 0 0 12px rgba(232, 85, 58, 0); }
}

.cover__hint {
  margin-top: 0.85rem;
  font-size: 0.85rem;
  color: var(--sky-blue);
  opacity: 0.8;
}

/* ============================================================
   Shared layout
   ============================================================ */
main {
  position: relative;
  z-index: 1;
}

section {
  position: relative;
  padding: 4.5rem 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

section.in-view {
  opacity: 1;
  transform: translateY(0);
}

.section-title {
  font-size: clamp(1.6rem, 5vw, 2.2rem);
  margin-bottom: 2rem;
}

/* ============================================================
   Hero
   ============================================================ */
.hero {
  min-height: 100vh;
  justify-content: center;
  padding-top: 3rem;
}

.orbits {
  position: absolute;
  top: 8%;
  left: 50%;
  width: min(420px, 90vw);
  height: min(420px, 90vw);
  transform: translateX(-50%);
  pointer-events: none;
  z-index: 0;
}

.orbit {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 2px dashed transparent;
}

.orbit--1 {
  border-top-color: var(--sky-blue);
  border-right-color: var(--lavender);
  animation: spin 22s linear infinite;
}

.orbit--2 {
  inset: 8%;
  border-bottom-color: var(--flame-gold);
  border-left-color: var(--rust-orange);
  animation: spin-reverse 18s linear infinite;
}

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

@keyframes spin-reverse {
  to { transform: rotate(-360deg); }
}

.sparkles {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
}

.sparkle {
  position: absolute;
  font-size: 1.4rem;
  animation: sparkle-twinkle 2.6s ease-in-out infinite;
}

@keyframes sparkle-twinkle {
  0%, 100% { opacity: 0.2; transform: scale(0.7) rotate(0deg); }
  50% { opacity: 1; transform: scale(1.15) rotate(15deg); }
}

.avatar-frame {
  position: relative;
  z-index: 1;
  width: min(280px, 70vw);
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  overflow: hidden;
  border: 6px solid var(--white-soft);
  box-shadow: 0 0 0 4px rgba(255, 255, 255, 0.35), 0 18px 28px rgba(74, 63, 53, 0.18);
  animation: float 3.2s ease-in-out infinite;
}

.avatar {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transform: scale(1.18);
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-16px); }
}

.hero__title {
  position: relative;
  z-index: 1;
  margin-top: 2rem;
  font-size: clamp(2rem, 8vw, 3.2rem);
  animation: pop-in 0.8s ease 0.2s both;
}

.hero__subtitle {
  position: relative;
  z-index: 1;
  margin-top: 0.75rem;
  font-size: clamp(1rem, 3vw, 1.2rem);
  color: var(--teal-dark);
  font-weight: 600;
}

@keyframes pop-in {
  0% { opacity: 0; transform: translateY(16px) scale(0.96); }
  60% { opacity: 1; transform: translateY(-4px) scale(1.02); }
  100% { opacity: 1; transform: translateY(0) scale(1); }
}

/* ============================================================
   Twins / personality cards
   ============================================================ */
.twins {
  padding-bottom: 3rem;
}

.twin-cards {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.5rem;
  width: 100%;
  max-width: 640px;
  perspective: 1200px;
}

.twin-card {
  flex: 1 1 220px;
  max-width: 280px;
  height: 200px;
  background: none;
  padding: 0;
}

.twin-card__inner {
  position: relative;
  width: 100%;
  height: 100%;
  border-radius: var(--radius);
  transition: transform 0.6s cubic-bezier(0.4, 0.2, 0.2, 1);
  transform-style: preserve-3d;
  box-shadow: var(--shadow-soft);
}

.twin-card:hover .twin-card__inner,
.twin-card:focus-visible .twin-card__inner,
.twin-card.is-flipped .twin-card__inner {
  transform: rotateY(180deg);
}

.twin-card__face {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  padding: 1.5rem;
  border-radius: var(--radius);
  backface-visibility: hidden;
}

.twin-card__face--front {
  background: var(--white-soft);
}

.twin-card__face--back {
  transform: rotateY(180deg);
  font-size: 0.98rem;
  line-height: 1.5;
}

.twin-card--cool .twin-card__face--front {
  background: linear-gradient(150deg, var(--sky-blue), var(--lavender));
}

.twin-card--cool .twin-card__face--back {
  background: linear-gradient(150deg, var(--lavender), var(--sky-blue));
  color: var(--text-dark);
}

.twin-card--warm .twin-card__face--front {
  background: linear-gradient(150deg, var(--flame-gold), var(--flame-orange));
}

.twin-card--warm .twin-card__face--back {
  background: linear-gradient(150deg, var(--flame-orange), var(--flame-red));
  color: var(--white-soft);
}

.twin-card__icon {
  font-size: 2.6rem;
}

.twin-card h3 {
  font-size: 1.3rem;
}

.twins__hint {
  margin-top: 1.5rem;
  font-size: 0.95rem;
  color: var(--teal-dark);
  font-weight: 600;
}

/* ============================================================
   Numerology 11
   ============================================================ */
.candles {
  display: flex;
  gap: 2.5rem;
  margin-bottom: 1.75rem;
}

.candle {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.flame {
  width: 22px;
  height: 30px;
  margin-bottom: 6px;
  border-radius: 50% 50% 50% 50% / 60% 60% 40% 40%;
  background: radial-gradient(circle at 50% 30%, var(--flame-gold) 0%, var(--flame-orange) 55%, var(--flame-red) 100%);
  box-shadow: 0 0 18px rgba(255, 140, 66, 0.6);
  animation: flicker 1.6s ease-in-out infinite;
  transform-origin: bottom center;
}

.candle:nth-child(2) .flame {
  animation-delay: 0.4s;
}

@keyframes flicker {
  0%, 100% { transform: scaleY(1) scaleX(1) rotate(0deg); opacity: 1; }
  25% { transform: scaleY(1.08) scaleX(0.95) rotate(-2deg); opacity: 0.92; }
  50% { transform: scaleY(0.94) scaleX(1.05) rotate(2deg); opacity: 1; }
  75% { transform: scaleY(1.05) scaleX(0.97) rotate(-1deg); opacity: 0.95; }
}

.stick {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 110px;
  font-family: var(--font-heading);
  font-size: 2.4rem;
  font-weight: 800;
  color: var(--white-soft);
  background: linear-gradient(180deg, var(--rust-orange), var(--teal));
  border-radius: 10px;
}

.numerology__text {
  max-width: 38rem;
  font-size: clamp(1rem, 3vw, 1.1rem);
  line-height: 1.7;
}

/* ============================================================
   Wish / message
   ============================================================ */
.wish {
  padding-bottom: 5rem;
}

.balloons {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

.balloon {
  position: absolute;
  bottom: -120px;
  width: 46px;
  height: 58px;
  border-radius: 50% 50% 50% 50% / 60% 60% 40% 40%;
  opacity: 0.55;
  animation: drift-up linear infinite;
}

.balloon::after {
  content: "";
  position: absolute;
  bottom: -22px;
  left: 50%;
  width: 1px;
  height: 22px;
  background: rgba(74, 63, 53, 0.25);
  transform: translateX(-50%);
}

@keyframes drift-up {
  0% { transform: translateY(0) translateX(0) rotate(0deg); opacity: 0; }
  10% { opacity: 0.55; }
  50% { transform: translateY(-55vh) translateX(20px) rotate(6deg); }
  90% { opacity: 0.45; }
  100% { transform: translateY(-110vh) translateX(-15px) rotate(-4deg); opacity: 0; }
}

.wish__card {
  position: relative;
  z-index: 1;
  max-width: 38rem;
  background: var(--white-soft);
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
  padding: clamp(1.75rem, 5vw, 3rem);
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
  text-align: left;
  font-size: clamp(1rem, 2.6vw, 1.1rem);
  line-height: 1.8;
}

.wish__greeting {
  font-family: var(--font-heading);
  font-size: clamp(1.3rem, 4vw, 1.6rem);
  font-weight: 700;
  color: var(--flame-red);
}

.wish__signature {
  font-family: var(--font-heading);
  font-weight: 700;
  text-align: right;
  color: var(--teal-dark);
}

/* ============================================================
   Footer
   ============================================================ */
.footer {
  padding: 2.5rem 1.5rem 4rem;
  gap: 1.25rem;
  opacity: 1;
  transform: none;
}

.footer p {
  font-weight: 600;
  color: var(--teal-dark);
}

.btn-replay {
  padding: 0.7rem 1.8rem;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1rem;
  color: var(--text-dark);
  background: var(--soft-yellow);
  border-radius: 999px;
  box-shadow: var(--shadow-soft);
  transition: transform 0.2s ease;
}

.btn-replay:hover,
.btn-replay:focus-visible {
  transform: translateY(-2px) scale(1.03);
}

/* ============================================================
   Responsive tweaks
   ============================================================ */
@media (min-width: 640px) {
  .avatar {
    width: 320px;
  }
}

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

  .star,
  .sparkle,
  .balloon,
  .orbit,
  .avatar,
  .gem-journey__gem,
  .gem-journey__earth,
  .gem-journey__spark,
  .gem-journey__number,
  .btn-open,
  .flame,
  .hero__title {
    animation: none !important;
  }

  .reveal-word {
    opacity: 1 !important;
    filter: none !important;
    animation: none !important;
  }

  .gem-journey__spark,
  .gem-journey__number {
    display: none !important;
  }

  .gem-journey__gem {
    top: 28% !important;
    left: 56% !important;
    opacity: 1 !important;
    transform: scale(0.9) !important;
  }

  section,
  .cover {
    transition: none !important;
  }

  .twin-card__inner {
    transition: none !important;
  }
}