:root {
  --forest: #0E3B33;
  --forest-2: #0A2C26;
  --cream: #FBF3D8;
  --paper: #FFFDF1;
  --mint: #4FD1B5;
  --ink: #12312A;
  --muted: #5F7568;
  --line: rgba(14, 59, 51, 0.14);
  --shell: 1140px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background:
    repeating-linear-gradient(0deg, rgba(14, 59, 51, 0.035) 0 1px, transparent 1px 26px),
    var(--cream);
  color: var(--ink);
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.76;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
p { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img { display: block; max-width: 100%; height: auto; }
h1, h2, h3 { margin: 0; line-height: 1.3; font-weight: 800; }

.page-shell {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: var(--forest);
  border-bottom: 3px solid var(--mint);
}

.nav-shell {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 11px 24px;
  display: flex;
  align-items: center;
  gap: 18px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  white-space: nowrap;
  color: var(--cream);
}

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 8px;
  object-fit: cover;
  border: 1px solid rgba(251, 243, 216, 0.35);
}

.primary-nav { margin-left: auto; }

.primary-nav ul {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: 14.5px;
  color: rgba(251, 243, 216, 0.76);
}

.primary-nav a {
  display: inline-block;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
}

.primary-nav a:hover {
  color: var(--mint);
  border-bottom-color: var(--mint);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-download {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 17px;
  border-radius: 999px;
  background: var(--mint);
  color: #07211C;
  font-size: 14.5px;
  font-weight: 800;
}

.nav-download svg {
  width: 17px;
  height: 17px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2.2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.nav-download:hover { background: #6FE3C8; }

.menu-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border: 1px solid rgba(251, 243, 216, 0.3);
  border-radius: 8px;
  background: transparent;
  cursor: pointer;
  padding: 0;
}

.menu-toggle span {
  display: block;
  width: 16px;
  height: 2px;
  margin: 3px auto;
  background: var(--cream);
}

/* ---------- hero ---------- */
.hero {
  padding: 54px 0 50px;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 0.95fr);
  gap: 44px;
  align-items: center;
}

.hero-kicker {
  display: inline-block;
  font-size: 11.5px;
  letter-spacing: 0.16em;
  font-weight: 700;
  color: var(--forest);
  background: rgba(79, 209, 181, 0.28);
  border-radius: 999px;
  padding: 3px 12px;
}

.hero h1 {
  margin: 15px 0 10px;
  font-size: clamp(33px, 4.6vw, 54px);
  letter-spacing: 0.02em;
  color: var(--forest);
}

.hero-subtitle {
  font-size: clamp(16px, 1.85vw, 20px);
  font-weight: 700;
  color: #17705C;
}

.hero-lead {
  margin-top: 16px;
  max-width: 480px;
  color: var(--muted);
  font-size: 15.5px;
}

.hero-actions {
  margin-top: 26px;
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.button {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 26px;
  border-radius: 999px;
  font-weight: 800;
  font-size: 15.5px;
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.button svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2.2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.button-primary {
  background: var(--forest);
  color: var(--cream);
  box-shadow: 0 12px 24px rgba(14, 59, 51, 0.24);
}

.button-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 28px rgba(14, 59, 51, 0.3);
}

.button-large { padding: 15px 32px; font-size: 16.5px; }

.text-link {
  font-size: 14.5px;
  font-weight: 600;
  color: var(--muted);
  border-bottom: 1px dashed rgba(18, 49, 42, 0.3);
  padding-bottom: 2px;
}

.text-link:hover { color: #17705C; }

.hero-tags {
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 12.5px;
  color: var(--muted);
}

.hero-tags li {
  padding: 4px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--paper);
}

.hero-tags b { color: #17705C; }

/* ---------- hero shelf ---------- */
.shelf-row {
  background: linear-gradient(180deg, #11503F, #0B2F28);
  border-radius: 14px;
  padding: 18px 18px 12px;
  box-shadow: 0 20px 40px rgba(14, 59, 51, 0.22);
}

.shelf-tier { margin-bottom: 6px; }

.shelf-books {
  display: flex;
  align-items: flex-end;
  gap: 6px;
  padding: 0 6px;
}

.shelf-book {
  flex: 1 1 0;
  min-width: 0;
  height: 132px;
  border-radius: 3px 3px 0 0;
  background: linear-gradient(180deg, #FFFDF1, #F1E7C6);
  border: 1px solid rgba(251, 243, 216, 0.55);
  border-bottom: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 6px 2px 8px;
  color: var(--forest);
  overflow: hidden;
}

.shelf-book b {
  font-family: "Consolas", "SFMono-Regular", monospace;
  font-size: 10px;
  letter-spacing: 0;
  color: #6B7E5E;
}

.shelf-book i {
  font-style: normal;
  writing-mode: vertical-rl;
  letter-spacing: 0.14em;
  font-size: 12.5px;
  font-weight: 700;
}

.shelf-book:nth-child(2) { background: linear-gradient(180deg, #4FD1B5, #35B79C); color: #05221C; }
.shelf-book:nth-child(2) b { color: #0A3B31; }
.shelf-book:nth-child(4) { background: linear-gradient(180deg, #E9C46A, #D9B055); color: #2A1F05; }
.shelf-book:nth-child(4) b { color: #4A3A0D; }
.shelf-book:nth-child(6) { height: 150px; }
.shelf-book:nth-child(3) { height: 118px; }
.shelf-book:nth-child(5) { height: 140px; }

.shelf-tier:nth-child(2) .shelf-book:nth-child(1) { height: 112px; }
.shelf-tier:nth-child(2) .shelf-book:nth-child(3) { background: linear-gradient(180deg, #4FD1B5, #35B79C); color: #05221C; }
.shelf-tier:nth-child(2) .shelf-book:nth-child(3) b { color: #0A3B31; }
.shelf-tier:nth-child(2) .shelf-book:nth-child(5) { height: 126px; }

.shelf-plank {
  display: block;
  height: 9px;
  border-radius: 2px;
  background: linear-gradient(180deg, #D9C48C, #A98F51);
  box-shadow: 0 3px 0 rgba(0, 0, 0, 0.18);
}

.shelf-note {
  margin-top: 10px;
  font-size: 11.5px;
  color: rgba(251, 243, 216, 0.72);
  padding-left: 2px;
}

/* ---------- section shared ---------- */
section { padding: 50px 0; }

.section-heading {
  max-width: 660px;
  margin-bottom: 26px;
}

.section-heading .eyebrow {
  display: inline-block;
  font-size: 11.5px;
  letter-spacing: 0.18em;
  font-weight: 700;
  color: #17705C;
  margin-bottom: 9px;
}

.section-heading h2 {
  font-size: clamp(22px, 2.7vw, 30px);
  color: var(--forest);
}

.section-heading p:last-child {
  margin-top: 9px;
  color: var(--muted);
  font-size: 14.5px;
}

.section-heading-split {
  max-width: none;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
}

.section-heading-split > p {
  margin: 0 0 6px;
  color: var(--muted);
  font-size: 13.5px;
  white-space: nowrap;
}

/* ---------- features ---------- */
.features {
  background: var(--forest);
  border-top: 1px solid var(--forest);
  border-bottom: 1px solid var(--forest);
  color: var(--cream);
}

.features .section-heading .eyebrow { color: var(--mint); }
.features .section-heading h2 { color: var(--cream); }
.features .section-heading p:last-child { color: rgba(251, 243, 216, 0.72); }

.shelf-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.shelf-grid article {
  padding: 18px 17px 20px;
  border-radius: 10px;
  background: rgba(251, 243, 216, 0.06);
  border: 1px solid rgba(251, 243, 216, 0.18);
  border-bottom: 3px solid var(--mint);
}

.shelf-grid article:nth-child(2) { border-bottom-color: #E9C46A; }
.shelf-grid article:nth-child(3) { border-bottom-color: rgba(79, 209, 181, 0.6); }
.shelf-grid article:nth-child(4) { border-bottom-color: rgba(233, 196, 106, 0.6); }

.layer-no {
  display: inline-block;
  font-family: "Consolas", "SFMono-Regular", monospace;
  font-size: 11px;
  letter-spacing: 0.08em;
  color: #07211C;
  background: var(--mint);
  border-radius: 3px;
  padding: 1px 7px;
  margin-bottom: 10px;
}

.shelf-grid h3 {
  font-size: 16.5px;
  margin-bottom: 7px;
  color: var(--cream);
}

.shelf-grid p {
  font-size: 13.5px;
  color: rgba(251, 243, 216, 0.7);
}

/* ---------- shots ---------- */
.shelf-shots {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.shelf-shots figure {
  margin: 0;
  border-radius: 12px;
  overflow: hidden;
  background: var(--paper);
  border: 1px solid var(--line);
  box-shadow: 0 10px 22px rgba(14, 59, 51, 0.07);
}

.shelf-shots img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top center;
  background: #EAE2C6;
}

.shelf-shots figcaption {
  display: flex;
  align-items: baseline;
  gap: 7px;
  padding: 10px 13px 12px;
  font-size: 13px;
  font-weight: 700;
  color: var(--forest);
  border-top: 1px solid var(--line);
}

.shelf-shots figcaption b {
  font-family: "Consolas", "SFMono-Regular", monospace;
  font-size: 11px;
  color: #17705C;
}

.shelf-shots figcaption small {
  margin-left: auto;
  font-weight: 400;
  font-size: 11px;
  color: var(--muted);
}

.sample-note {
  margin-top: 15px;
  font-size: 12.5px;
  color: var(--muted);
}

/* ---------- faq ---------- */
.faq {
  background: #F6EFD2;
  border-top: 1px solid var(--line);
}

.faq-rows {
  display: grid;
  gap: 9px;
  max-width: 900px;
}

.faq-rows details {
  border-radius: 10px;
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 0 17px;
}

.faq-rows details[open] { border-color: rgba(79, 209, 181, 0.75); }

.faq-rows summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 0;
  cursor: pointer;
  list-style: none;
}

.faq-rows summary::-webkit-details-marker { display: none; }

.faq-rows summary h3 {
  flex: 1;
  font-size: 15.5px;
  color: var(--forest);
}

.faq-rows summary i {
  position: relative;
  flex: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: rgba(79, 209, 181, 0.25);
}

.faq-rows summary i::before,
.faq-rows summary i::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  background: #17705C;
  transform: translate(-50%, -50%);
}

.faq-rows summary i::before { width: 9px; height: 2px; }
.faq-rows summary i::after { width: 2px; height: 9px; transition: opacity 0.2s ease; }
.faq-rows details[open] summary i::after { opacity: 0; }

.faq-rows details > p {
  padding: 12px 0 15px;
  border-top: 1px dashed var(--line);
  font-size: 14px;
  color: var(--muted);
}

/* ---------- reviews ---------- */
.reviews {
  background: var(--forest);
  border-top: 1px solid var(--forest);
}

.reviews .section-heading .eyebrow { color: var(--mint); }
.reviews .section-heading h2 { color: var(--cream); }
.reviews .section-heading p:last-child { color: rgba(251, 243, 216, 0.72); }

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

.review-card {
  padding: 16px 17px;
  border-radius: 10px;
  background: rgba(251, 243, 216, 0.07);
  border: 1px solid rgba(251, 243, 216, 0.16);
}

.review-card:nth-child(3n + 2) { background: rgba(79, 209, 181, 0.12); }

.review-card > p {
  font-size: 13.6px;
  color: rgba(251, 243, 216, 0.88);
}

.review-meta {
  margin-top: 12px;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
  padding-top: 9px;
  border-top: 1px dashed rgba(251, 243, 216, 0.22);
  font-size: 10.5px;
  color: rgba(251, 243, 216, 0.6);
}

.review-meta b {
  font-size: 12px;
  color: var(--mint);
}

/* ---------- steps ---------- */
.pick-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.pick-row li {
  padding: 20px 20px 22px;
  border-radius: 10px;
  background: var(--paper);
  border: 1px solid var(--line);
  box-shadow: inset 0 3px 0 var(--mint);
}

.pick-row span {
  font-family: "Consolas", "SFMono-Regular", monospace;
  font-size: 11px;
  letter-spacing: 0.12em;
  color: #17705C;
}

.pick-row h3 {
  font-size: 17px;
  margin: 5px 0 6px;
  color: var(--forest);
}

.pick-row p {
  font-size: 13.6px;
  color: var(--muted);
}

/* ---------- download ---------- */
.download { padding-bottom: 62px; }

.download-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  padding: 32px;
  border-radius: 16px;
  background:
    radial-gradient(320px 200px at 92% 0%, rgba(79, 209, 181, 0.28), transparent 66%),
    var(--forest-2);
  border: 1px solid rgba(79, 209, 181, 0.4);
  color: var(--cream);
}

.download-copy { max-width: 520px; }

.download-copy .eyebrow {
  font-size: 11.5px;
  letter-spacing: 0.18em;
  font-weight: 700;
  color: var(--mint);
  margin-bottom: 8px;
}

.download-copy h2 {
  font-size: clamp(22px, 2.6vw, 29px);
  margin-bottom: 8px;
}

.download-copy p { font-size: 14.5px; color: rgba(251, 243, 216, 0.74); }

.download-act {
  flex: none;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 12px;
}

.download-panel .button-primary {
  background: var(--mint);
  color: #07211C;
  box-shadow: 0 12px 24px rgba(79, 209, 181, 0.25);
}

.download-notes {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 14px;
  font-size: 12px;
  color: rgba(251, 243, 216, 0.7);
}

.download-notes li {
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

.download-notes li::before {
  content: "";
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--mint);
}

/* ---------- footer ---------- */
.site-footer {
  background: var(--forest-2);
  border-top: 3px solid var(--mint);
  padding: 32px 0 28px;
  color: var(--cream);
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr) minmax(0, 0.85fr);
  gap: 20px 30px;
  align-items: start;
}

.footer-brand strong {
  display: block;
  font-size: 17px;
}

.footer-brand p {
  margin-top: 4px;
  font-size: 12.5px;
  color: rgba(251, 243, 216, 0.66);
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  font-size: 13px;
  color: rgba(251, 243, 216, 0.66);
}

.footer-nav a:hover { color: var(--mint); }

.footer-meta {
  font-size: 12.5px;
  color: rgba(251, 243, 216, 0.66);
  text-align: right;
}

.footer-meta a:hover { color: var(--mint); }

.disclaimer {
  grid-column: 1 / -1;
  padding-top: 15px;
  border-top: 1px solid rgba(251, 243, 216, 0.16);
  font-size: 12px;
  line-height: 1.7;
  color: rgba(251, 243, 216, 0.52);
}

/* ---------- responsive ---------- */
@media (max-width: 980px) {
  .hero-grid { grid-template-columns: minmax(0, 1fr); gap: 32px; }
  .shelf-row { max-width: 560px; }
  .shelf-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .shelf-shots { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .note-wall { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-meta { text-align: left; }
  .download-panel { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 900px) {
  .primary-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin-left: 0;
    display: none;
    background: var(--forest);
    border-bottom: 2px solid var(--mint);
    padding: 8px 24px 14px;
  }

  .primary-nav.is-open { display: block; }

  .primary-nav ul {
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    font-size: 15px;
  }

  .primary-nav li { width: 100%; }

  .primary-nav a {
    display: block;
    padding: 11px 0;
    border-bottom: 1px solid rgba(251, 243, 216, 0.12);
  }

  .primary-nav a:hover { border-bottom-color: rgba(251, 243, 216, 0.12); }

  .nav-shell { position: relative; flex-wrap: wrap; }
  .primary-nav { order: 4; flex-basis: 100%; }
  .nav-actions { margin-left: auto; }
  .menu-toggle { display: block; }
  .nav-download span { display: none; }
  .nav-download { padding: 10px 12px; }
}

@media (max-width: 640px) {
  .page-shell, .nav-shell { padding-left: 18px; padding-right: 18px; }
  section { padding: 40px 0; }
  .hero { padding: 38px 0 34px; }
  .shelf-grid { grid-template-columns: minmax(0, 1fr); }
  .note-wall { grid-template-columns: minmax(0, 1fr); }
  .pick-row { grid-template-columns: minmax(0, 1fr); }
  .section-heading-split { flex-direction: column; align-items: flex-start; gap: 6px; }
  .section-heading-split > p { white-space: normal; }
  .download-panel { padding: 24px 18px; }
  .download-act { width: 100%; }
  .download-act .button { width: 100%; justify-content: center; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .shelf-book { height: 112px; }
  .shelf-book i { font-size: 11.5px; letter-spacing: 0.08em; }
  .shelf-tier:nth-child(2) .shelf-book:nth-child(1) { height: 100px; }
}

@media (max-width: 400px) {
  .shelf-shots { grid-template-columns: minmax(0, 1fr); }
  .brand span { font-size: 15px; }
  .shelf-row { padding: 12px 12px 8px; }
  .shelf-books { gap: 4px; padding: 0 2px; }
  .shelf-book { height: 100px; padding: 5px 1px 6px; }
  .shelf-book b { font-size: 9px; }
  .shelf-book i { font-size: 10.5px; }
}