:root {
  --text: #f7f8f7;
  --muted: rgba(241, 245, 240, 0.82);
  --border: rgba(203, 214, 205, 0.16);
  --green: #1fd35d;
  --green-2: #11923f;
  --glow: rgba(31, 211, 93, 0.28);
  --blue-1: #16a7ff;
  --blue-2: #10d3ff;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  background:
    radial-gradient(circle at top center, rgba(31, 211, 93, 0.16), transparent 24%),
    radial-gradient(circle at 50% 18%, rgba(31, 211, 93, 0.1), transparent 28%),
    linear-gradient(180deg, #030403 0%, #020302 100%);
  color: var(--text);
  font-family: "Montserrat", "Segoe UI", "Helvetica Neue", Arial, sans-serif;
}

.ebook-page {
  width: min(100%, 1000px);
  margin: 0 auto;
  padding: clamp(12px, 2vw, 24px);
}

.ebook-shell {
  position: relative;
  max-width: 430px;
  margin: 0 auto;
  padding: 14px 12px 28px;
}

.back-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 16px;
  margin-bottom: 16px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: 999px;
  background: linear-gradient(90deg, var(--green), var(--green-2));
  color: #fff;
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 700;
  box-shadow:
    0 10px 25px rgba(16, 112, 48, 0.3),
    inset 0 1px 1px rgba(255, 255, 255, 0.25);
  transition: transform 0.2s ease, filter 0.2s ease, box-shadow 0.2s ease;
}

.back-link:hover {
  transform: translateY(-2px);
  filter: brightness(1.04);
  box-shadow:
    0 14px 28px rgba(16, 112, 48, 0.36),
    inset 0 1px 1px rgba(255, 255, 255, 0.25);
}

.back-link:focus-visible {
  outline: 2px solid rgba(255, 255, 255, 0.7);
  outline-offset: 3px;
}

.top-accent {
  display: block;
  width: 100%;
  height: 4px;
  border-radius: 999px;
  margin-bottom: 18px;
  background: linear-gradient(90deg, transparent 0%, var(--green) 8%, var(--green) 92%, transparent 100%);
  box-shadow: 0 0 20px var(--glow);
}

.hero-card {
  position: relative;
  display: grid;
  justify-items: center;
  gap: 18px;
  padding: 10px 10px 0;
}

.hero-left {
  display: grid;
  justify-items: center;
  gap: 18px;
}

.hero-right {
  width: 100%;
}

.book-frame {
  position: relative;
  width: min(100%, 270px);
  padding: 10px 0 6px;
}

.book-frame::before {
  content: "";
  position: absolute;
  inset: 4% -12% 10% -12%;
  background: radial-gradient(circle, rgba(31, 211, 93, 0.34), rgba(31, 211, 93, 0.06) 58%, transparent 78%);
  filter: blur(8px);
}

.book-frame img {
  position: relative;
  width: 100%;
  height: auto;
  display: block;
  filter: drop-shadow(0 22px 26px rgba(0, 0, 0, 0.44));
}

.spinning-book {
  animation: bookPremiumFloat 5s ease-in-out infinite;
  transform-origin: center center;
  will-change: transform;
  transform-style: preserve-3d;
  backface-visibility: hidden;
}

@keyframes bookPremiumFloat {
  0% {
    transform: perspective(1200px) rotateY(-12deg) rotateX(2deg) translateY(0);
  }
  25% {
    transform: perspective(1200px) rotateY(-4deg) rotateX(0deg) translateY(-6px);
  }
  50% {
    transform: perspective(1200px) rotateY(10deg) rotateX(-1deg) translateY(0);
  }
  75% {
    transform: perspective(1200px) rotateY(4deg) rotateX(1deg) translateY(-6px);
  }
  100% {
    transform: perspective(1200px) rotateY(-12deg) rotateX(2deg) translateY(0);
  }
}

.cta-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 168px;
  min-height: 46px;
  padding: 0 22px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--green), var(--green-2));
  color: #f5fff8;
  text-decoration: none;
  font-size: clamp(0.95rem, 3.2vw, 1rem);
  font-weight: 800;
  box-shadow: 0 12px 22px rgba(16, 112, 48, 0.3);
}

.intro-copy h1 {
  font-size: clamp(1.3rem, 5vw, 2.1rem);
  line-height: 1.08;
  letter-spacing: -0.03em;
  font-weight: 800;
}

.intro-copy h1 strong {
  color: inherit;
  font-style: italic;
  text-decoration-line: underline;
  text-decoration-color: var(--green);
  text-decoration-thickness: 3px;
  text-underline-offset: 3px;
}

.intro-copy p,
.copy-block p {
  margin-top: 14px;
  color: var(--muted);
  font-size: clamp(0.84rem, 2.7vw, 0.96rem);
  line-height: 1.5;
}

.content-card {
  margin-top: 18px;
  padding: 20px 14px 18px;
  border: 1px solid var(--border);
  border-radius: 22px;
  background:
    radial-gradient(circle at top right, rgba(31, 211, 93, 0.08), transparent 22%),
    linear-gradient(180deg, rgba(10, 13, 10, 0.98), rgba(5, 7, 5, 0.98));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.04);
}

.pillars-card {
  padding: 16px 14px;
  border: 1px solid var(--border);
  border-radius: 18px;
  background: rgba(5, 7, 5, 0.74);
}

.pillars-list {
  list-style: none;
  display: grid;
  gap: 12px;
}

.pillars-list li {
  position: relative;
  padding-left: 14px;
  font-size: clamp(0.84rem, 2.8vw, 0.96rem);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.pillars-list li::before {
  content: "\2022";
  position: absolute;
  left: 0;
  top: 0;
  color: #ffffff;
}

.pillars-list li::after {
  content: "";
  display: block;
  width: clamp(88px, 28vw, 144px);
  height: 3px;
  margin-top: 5px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--green), #2be772);
  box-shadow: 0 0 14px rgba(31, 211, 93, 0.24);
}

.copy-block {
  margin-top: 18px;
}

.cta-bottom {
  margin-top: 22px;
  width: 100%;
}

.brand-lockup {
  display: block;
  margin-top: 18px;
  padding: 0 4px;
}

.brand-logo-image {
  display: block;
  width: min(100%, 360px);
  height: auto;
}

.details-grid {
  margin-top: 22px;
}

@media (min-width: 760px) {
  .ebook-page {
    width: min(100%, 1240px);
    padding: 18px 28px 34px;
  }

  .ebook-shell {
    max-width: 1180px;
    padding: 10px 4px 26px;
  }

  .top-accent {
    height: 5px;
    margin-bottom: 16px;
    background: linear-gradient(90deg, #17de65, #14d65f);
    box-shadow: 0 0 18px rgba(31, 211, 93, 0.24);
  }

  .hero-card {
    grid-template-columns: 340px minmax(0, 1fr);
    align-items: start;
    justify-items: stretch;
    gap: 34px;
    padding: 8px 4px 26px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.18);
  }

  .book-frame {
    width: min(100%, 255px);
    margin: 0 auto;
    padding: 4px 0 0;
  }

  .hero-left .cta-button {
    min-width: 248px;
    min-height: 52px;
    font-size: 0.98rem;
  }

  .intro-copy h1 {
    font-size: clamp(2.05rem, 3.1vw, 3.15rem);
    line-height: 1;
    max-width: 640px;
    margin-top: 4px;
  }

  .intro-copy p,
  .copy-block p {
    font-size: clamp(0.95rem, 1.1vw, 1.1rem);
    line-height: 1.42;
    max-width: 700px;
  }

  .content-card {
    margin-top: 0;
    padding: 24px 4px 0;
    border: 0;
    border-radius: 0;
    background: transparent;
    box-shadow: none;
  }

  .details-grid {
    margin-top: 0;
    display: grid;
    grid-template-columns: 340px minmax(0, 1fr);
    gap: 34px;
    align-items: start;
  }

  .pillars-card {
    min-height: 320px;
    padding: 24px 26px 28px;
    border-radius: 30px;
    border-color: rgba(203, 214, 205, 0.22);
    background: rgba(4, 6, 4, 0.86);
  }

  .pillars-list {
    gap: 16px;
  }

  .pillars-list li {
    font-size: 0.95rem;
    letter-spacing: 0.01em;
  }

  .pillars-list li::after {
    width: clamp(110px, 16vw, 190px);
    margin-top: 7px;
  }

  .details-copy {
    padding-top: 4px;
  }

  .copy-block {
    margin-top: 0;
    max-width: 700px;
  }

  .cta-bottom {
    width: auto;
    min-width: 240px;
    margin-top: 22px;
  }

  .brand-lockup {
    margin-top: 24px;
    padding: 0;
  }

  .brand-logo-image {
    width: min(100%, 500px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .spinning-book {
    animation: none;
    transform: none;
  }
}