:root {
  color-scheme: dark;

  --bg0: #05060b;
  --bg1: #0b0d18;
  --ink: rgba(255, 255, 255, 0.92);
  --muted: rgba(255, 255, 255, 0.65);
  --muted2: rgba(255, 255, 255, 0.45);

  /* 神秘渐变：用变量，便于后续随机化（两层 Linear Gradient） */
  /* 固定一套“深蓝紫”方案：不随刷新变化 */
  --gA-angle: 145deg;
  --gA-1: #1a1f4f;
  --gA-2: #6b2cff;
  --gB-angle: 18deg;
  --gB-1: #0b1231;
  --gB-2: #ff4fd8;
  --g-noise: rgba(255, 255, 255, 0.06);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  background:
    radial-gradient(900px 700px at 18% 15%, rgba(90, 92, 255, 0.18), transparent 60%),
    radial-gradient(900px 700px at 84% 25%, rgba(255, 79, 216, 0.14), transparent 60%),
    radial-gradient(900px 700px at 55% 90%, rgba(45, 243, 209, 0.12), transparent 55%),
    linear-gradient(180deg, var(--bg1), var(--bg0));
  color: var(--ink);
  -webkit-tap-highlight-color: transparent;
  position: relative;
  overflow-x: hidden;
}

.stage {
  position: relative;
  z-index: 1;
}

/* 背景流动光晕（沉浸感，低强度） */
body::before,
body::after {
  content: "";
  position: fixed;
  inset: -20vmax;
  pointer-events: none;
  z-index: 0;
  opacity: 0.55;
  filter: blur(28px) saturate(1.1);
  transform: translate3d(0, 0, 0);
  will-change: transform;
}

body::before {
  background:
    radial-gradient(900px 700px at 20% 20%, rgba(88, 98, 255, 0.16), transparent 62%),
    radial-gradient(900px 700px at 82% 28%, rgba(255, 79, 216, 0.12), transparent 62%),
    radial-gradient(900px 700px at 55% 85%, rgba(150, 120, 255, 0.1), transparent 60%);
  animation: bg-drift-a 18s ease-in-out infinite alternate;
}

body::after {
  opacity: 0.38;
  background:
    radial-gradient(1100px 760px at 60% 35%, rgba(255, 255, 255, 0.06), transparent 65%),
    radial-gradient(900px 700px at 35% 70%, rgba(60, 90, 255, 0.08), transparent 62%),
    radial-gradient(900px 700px at 78% 78%, rgba(255, 79, 216, 0.06), transparent 62%);
  animation: bg-drift-b 24s ease-in-out infinite alternate;
}

@keyframes bg-drift-a {
  0% {
    transform: translate3d(-2%, -1%, 0) scale(1.02);
  }
  100% {
    transform: translate3d(2%, 1%, 0) scale(1.04);
  }
}

@keyframes bg-drift-b {
  0% {
    transform: translate3d(1%, -2%, 0) scale(1.01);
  }
  100% {
    transform: translate3d(-1%, 2%, 0) scale(1.03);
  }
}

.stage {
  min-height: 100%;
  display: grid;
  place-items: center;
  padding: 28px 16px;
}

.card-wrap {
  perspective: 1100px;
  perspective-origin: 50% 45%;
}

.card {
  width: clamp(260px, 36vw, 360px);
  aspect-ratio: 5 / 8; /* 1 : 1.6 */
  border-radius: 22px;
  cursor: pointer;
  outline: none;
  position: relative;
  transform: rotateX(var(--tilt-x, 0deg)) rotateY(var(--tilt-y, 0deg));
  transform-style: preserve-3d;
  transition: transform 160ms ease-out;
}

.card:hover {
  transition: transform 90ms ease-out;
}

.card:focus-visible {
  box-shadow:
    0 0 0 3px rgba(255, 255, 255, 0.08),
    0 0 0 6px rgba(90, 92, 255, 0.25);
}

.card__inner {
  position: absolute;
  inset: 0;
  border-radius: inherit;
  transform-style: preserve-3d;
  transition: transform 720ms cubic-bezier(0.2, 0.75, 0.2, 1);
  will-change: transform;
}

.card.is-flipped .card__inner {
  transform: rotateY(180deg);
}

.card__face {
  position: absolute;
  inset: 0;
  border-radius: inherit;
  overflow: hidden;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;

  display: grid;
  place-items: center;
}

.card__face::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.14),
    inset 0 0 0 2px rgba(0, 0, 0, 0.45);
}

.card__face--front {
  background:
    radial-gradient(900px 700px at 50% 18%, rgba(255, 255, 255, 0.04), transparent 55%),
    linear-gradient(180deg, rgba(10, 12, 22, 0.92), rgba(4, 5, 11, 0.96));
}

.card__face--front::before {
  content: "";
  position: absolute;
  inset: 16px;
  border-radius: 16px;
  pointer-events: none;
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.18),
    inset 0 0 0 3px rgba(0, 0, 0, 0.55);
  opacity: 0.95;
}

.card__face--front::after {
  content: "";
  position: absolute;
  inset: -1px;
  pointer-events: none;
  background:
    radial-gradient(820px 540px at var(--mx, 50%) var(--my, 45%), rgba(255, 255, 255, 0.16), transparent 60%),
    radial-gradient(560px 420px at calc(var(--mx, 50%) + 10%) calc(var(--my, 45%) + 8%), rgba(90, 92, 255, 0.12), transparent 62%),
    linear-gradient(120deg, rgba(120, 120, 255, 0.06), rgba(255, 79, 216, 0.06));
  mix-blend-mode: soft-light;
  opacity: 0.18;
  filter: saturate(1.25) contrast(1.06);
}

.card__pattern {
  position: absolute;
  inset: -2px;
  background:
    linear-gradient(var(--gA-angle), var(--gA-1), var(--gA-2)),
    linear-gradient(var(--gB-angle), var(--gB-1), var(--gB-2));
  background-blend-mode: overlay;
  filter: saturate(1.02) contrast(1.06);
  transform: scale(1.02);
  opacity: 0.58;
}

.card__pattern::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    /* 星点 + 细噪点（更塔罗、更暗） */
    radial-gradient(2px 2px at 18% 22%, rgba(255, 255, 255, 0.16), transparent 60%),
    radial-gradient(1.5px 1.5px at 72% 28%, rgba(255, 255, 255, 0.13), transparent 60%),
    radial-gradient(1.5px 1.5px at 36% 62%, rgba(255, 255, 255, 0.12), transparent 60%),
    radial-gradient(2px 2px at 78% 72%, rgba(255, 255, 255, 0.14), transparent 60%),
    radial-gradient(1.5px 1.5px at 24% 78%, rgba(255, 255, 255, 0.11), transparent 60%),
    repeating-linear-gradient(45deg, transparent 0 10px, rgba(255, 255, 255, 0.035) 10px 11px);
  mix-blend-mode: soft-light;
  opacity: 0.72;
}

.card:hover .card__face--front::after {
  opacity: 0.42;
}

.card__pattern::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(1200px 900px at 50% 40%, transparent 52%, rgba(0, 0, 0, 0.6) 100%),
    linear-gradient(180deg, rgba(0, 0, 0, 0.15), transparent 30%, rgba(0, 0, 0, 0.32));
}

.card__front-content {
  position: relative;
  z-index: 1;
  text-align: center;
  width: min(82%, 320px);
  padding: 0;
  display: grid;
  justify-items: center;
  align-content: center;
  gap: 12px;
}

.card__front-content::before,
.card__front-content::after {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  color: rgba(255, 255, 255, 0.62);
  letter-spacing: 0.12em;
  font-weight: 600;
  pointer-events: none;
  text-shadow: 0 10px 22px rgba(0, 0, 0, 0.55);
}

.card__front-content::before {
  content: "☾  ✶  ☾";
  top: -34px;
  font-size: 12px;
  opacity: 0.78;
}

.card__front-content::after {
  content: "✦  ✷  ✦";
  bottom: -34px;
  font-size: 12px;
  opacity: 0.66;
}

.card__kicker {
  font-size: 12px;
  letter-spacing: 0.42em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.72);
  margin: 0;
  transform: translateX(0.21em);
}

.card__title {
  font-size: 24px;
  font-weight: 850;
  letter-spacing: 0.06em;
  line-height: 1.2;
  margin: 0;
  text-shadow:
    0 14px 34px rgba(0, 0, 0, 0.62),
    0 2px 0 rgba(0, 0, 0, 0.22);
}

.card__title::after {
  content: "";
  display: block;
  width: 64px;
  height: 1px;
  margin: 14px auto 0;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.34), transparent);
  opacity: 0.9;
}

.card__face--back {
  transform: rotateY(180deg);
  background:
    radial-gradient(900px 600px at 22% 18%, rgba(110, 110, 255, 0.12), transparent 60%),
    radial-gradient(800px 600px at 84% 30%, rgba(190, 110, 255, 0.1), transparent 62%),
    linear-gradient(180deg, rgba(16, 20, 44, 0.92), rgba(7, 9, 19, 0.96));
  border: 1px solid rgba(255, 255, 255, 0.12);
}

.card__back-content {
  width: 100%;
  height: 100%;
  padding: 26px 22px;
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 14px;
  justify-items: center;
  text-align: center;
}

.card__back-title {
  font-size: 14px;
  letter-spacing: 0.18em;
  color: rgba(255, 255, 255, 0.78);
  text-transform: uppercase;
}

.card__quote {
  margin: 0;
  align-self: center;
  justify-self: center;
  font-size: 18px;
  line-height: 1.55;
  color: var(--ink);
  text-wrap: balance;
  max-width: 22ch;
}

.card__hint {
  font-size: 12px;
  color: var(--muted2);
}

/* 立体阴影与边框 */
.card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  box-shadow:
    0 26px 70px rgba(0, 0, 0, 0.55),
    0 10px 30px rgba(0, 0, 0, 0.38);
  opacity: 1;
  pointer-events: none;
}

@media (prefers-reduced-motion: reduce) {
  .card__inner {
    transition: none;
  }
  body::before,
  body::after {
    animation: none;
  }
}