:root {
  color-scheme: light;
  --ink: #17394a;
  --muted: #5e7b89;
  --sky: #dff4ff;
  --sky-deep: #b9e5f7;
  --mint: #dff4e8;
  --peach: #ffdcca;
  --butter: #fff1bb;
  --lilac: #e9e1f8;
  --paper: rgba(255, 255, 255, 0.9);
  --line: rgba(67, 128, 157, 0.19);
  --shadow: 0 18px 42px rgba(43, 97, 121, 0.13);
  font-family: "Avenir Next", "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  min-width: 320px;
  background: #f8fcff;
}

body {
  min-height: 100svh;
  margin: 0;
  overflow-x: hidden;
  color: var(--ink);
  background:
    radial-gradient(circle at 15% 12%, rgba(255, 220, 202, 0.62), transparent 27rem),
    radial-gradient(circle at 88% 24%, rgba(233, 225, 248, 0.78), transparent 25rem),
    linear-gradient(165deg, #fafdff 0%, var(--sky) 52%, #f7fcff 100%);
}

a {
  color: inherit;
}

.site-header {
  position: relative;
  z-index: 2;
  width: min(92vw, 780px);
  margin: 0 auto;
  padding: 2.35rem 1rem 0;
  text-align: center;
}

.spark {
  display: inline-grid;
  width: 2rem;
  height: 2rem;
  place-items: center;
  margin-bottom: 0.2rem;
  border: 1px solid rgba(45, 111, 141, 0.14);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.68);
  color: #d68070;
  box-shadow: 0 8px 25px rgba(46, 111, 140, 0.08);
  font-size: 0.8rem;
}

.site-header h1 {
  margin: 0;
  font-size: clamp(2.55rem, 12vw, 5.15rem);
  font-weight: 650;
  letter-spacing: -0.055em;
  line-height: 0.98;
  text-wrap: balance;
}

.site-header p {
  margin: 0.75rem 0 0;
  color: var(--muted);
  font-size: clamp(0.88rem, 3.3vw, 1.02rem);
  letter-spacing: 0.08em;
  text-transform: lowercase;
}

.recommendations {
  position: relative;
  z-index: 1;
  width: 100%;
}

.orbit-stage {
  position: relative;
  width: calc(100% - 1.25rem);
  max-width: 520px;
  height: clamp(570px, 70svh, 650px);
  margin: 0.6rem auto 0;
  isolation: isolate;
}

.book-orbit {
  position: absolute;
  inset: 0;
  margin: 0;
  padding: 0;
  list-style: none;
}

.book-node {
  position: absolute;
  top: 50%;
  left: 50%;
  width: min(40vw, 154px);
  will-change: left, top, transform;
}

.book-link {
  display: block;
  text-decoration: none;
  transform: rotate(var(--tilt, 0deg));
  transform-origin: center;
  transition: transform 180ms ease, filter 180ms ease;
  -webkit-tap-highlight-color: transparent;
}

.book-link:hover {
  transform: translateY(-5px) rotate(var(--tilt, 0deg));
  filter: saturate(1.04);
}

.book-link:focus-visible {
  outline: 3px solid rgba(39, 113, 149, 0.5);
  outline-offset: 6px;
  border-radius: 23px;
}

.book-card {
  margin: 0;
  padding: 0.58rem;
  border: 1px solid rgba(55, 116, 145, 0.14);
  border-radius: 21px;
  background: var(--paper);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.book-cover {
  overflow: hidden;
  aspect-ratio: 3 / 4;
  border-radius: 15px;
  background: var(--sky-deep);
}

.book-cover img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.book-card figcaption {
  display: grid;
  gap: 0.25rem;
  padding: 0.7rem 0.3rem 0.22rem;
}

.book-title {
  font-size: clamp(0.9rem, 3.6vw, 1rem);
  font-weight: 690;
  letter-spacing: -0.02em;
  line-height: 1.34;
}

.book-author {
  color: var(--muted);
  font-size: clamp(0.72rem, 2.8vw, 0.82rem);
  line-height: 1.3;
}

.orbit-ring,
.orbit-center {
  position: absolute;
  top: 50%;
  left: 50%;
  pointer-events: none;
}

.orbit-ring {
  border: 1px dashed rgba(55, 121, 151, 0.2);
  border-radius: 50%;
  transform: translate(-50%, -50%) rotate(-8deg);
}

.orbit-ring--outer {
  width: 66%;
  height: 54%;
}

.orbit-ring--inner {
  width: 49%;
  height: 39%;
  border-style: solid;
  border-color: rgba(255, 255, 255, 0.52);
  transform: translate(-50%, -50%) rotate(10deg);
}

.orbit-center {
  display: grid;
  width: 3.35rem;
  height: 3.35rem;
  place-items: center;
  border: 1px solid rgba(69, 124, 148, 0.14);
  border-radius: 50%;
  background: linear-gradient(135deg, var(--butter), #fff8d9);
  box-shadow: 0 12px 35px rgba(74, 114, 131, 0.12);
  transform: translate(-50%, -50%);
}

.orbit-center span {
  font-size: 0.74rem;
  font-weight: 750;
  letter-spacing: 0.08em;
}

.orbit-hint {
  width: fit-content;
  margin: -0.7rem auto 0;
  padding: 0.48rem 0.75rem;
  border: 1px solid rgba(50, 111, 140, 0.12);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.58);
  color: var(--muted);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
}

.ambient-shape {
  position: fixed;
  z-index: 0;
  border-radius: 50%;
  pointer-events: none;
  filter: blur(1px);
  opacity: 0.68;
}

.ambient-shape--one {
  top: 12%;
  left: -4rem;
  width: 9rem;
  height: 9rem;
  background: var(--mint);
}

.ambient-shape--two {
  right: -4.5rem;
  bottom: 8%;
  width: 11rem;
  height: 11rem;
  background: var(--peach);
}

.visually-hidden {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0, 0, 0, 0) !important;
  white-space: nowrap !important;
  border: 0 !important;
}

.no-js .orbit-stage {
  height: auto;
  padding: 2rem 0;
}

.no-js .orbit-ring,
.no-js .orbit-center {
  display: none;
}

.no-js .book-orbit {
  position: static;
  display: grid;
  gap: 1.25rem;
  justify-items: center;
}

.no-js .book-node {
  position: static;
  width: min(78vw, 240px);
  transform: none !important;
}

@media (min-width: 720px) {
  .site-header {
    padding-top: 3.2rem;
  }

  .orbit-stage {
    width: min(94vw, 1080px);
    max-width: 1080px;
    height: clamp(650px, 72vh, 780px);
    margin-top: 0.2rem;
  }

  .book-node {
    width: clamp(190px, 18vw, 220px);
  }

  .book-title {
    font-size: 1.04rem;
  }

  .book-author {
    font-size: 0.82rem;
  }

  .orbit-ring--outer {
    width: 72%;
    height: 58%;
  }

  .orbit-ring--inner {
    width: 54%;
    height: 42%;
  }

  .orbit-hint {
    margin-top: -1.15rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.001ms !important;
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
  }
}