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

:root {
  --bg: #05051a;
  --purple: #7c3aed;
  --blue: #3b82f6;
  --purple-light: #a78bfa;
  --blue-light: #93c5fd;
  --text-muted: #9ca3af;
  --border: rgba(255,255,255,0.08);
}

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: #fff;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  overflow-x: hidden;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ── Header ── */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  background: rgba(5,5,26,0.8);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
}
.logo-icon {
  width: 40px; height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--purple), var(--blue));
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 0 20px rgba(124,58,237,0.3);
  transition: transform 0.2s;
}
.logo:hover .logo-icon { transform: scale(1.1); }
.logo-spinner {
  width: 24px; height: 24px;
  border: 2px solid rgba(255,255,255,0.8);
  border-top-color: transparent;
  border-radius: 50%;
  animation: spin 1.5s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.logo-text { font-size: 20px; font-weight: 700; letter-spacing: 0.1em; }

.nav { display: flex; align-items: center; gap: 32px; }
.nav-btn {
  background: none; border: none; color: var(--text-muted);
  font-size: 14px; font-weight: 500; cursor: pointer;
  transition: color 0.2s;
}
.nav-btn:hover, .nav-btn.active { color: var(--purple-light); }
.lang-selector {
  display: flex; align-items: center; gap: 8px;
  background: rgba(255,255,255,0.05);
  padding: 6px 12px; border-radius: 8px;
  border: 1px solid var(--border);
  cursor: pointer; font-size: 14px; font-weight: 500;
  color: var(--text-muted);
  transition: background 0.2s;
}
.lang-selector:hover { background: rgba(255,255,255,0.1); }

/* ── Pages ── */
.page { display: none; flex: 1; }
.page.active { display: block; }

/* ── Hero ── */
.hero {
  padding-top: 80px;
  min-height: 100vh;
  display: flex;
  align-items: center;
}
.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
  padding: 80px 24px;
}
@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; text-align: center; }
  .hero-buttons { justify-content: center; }
}
.hero-text h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}
.gradient-text {
  background: linear-gradient(90deg, var(--purple-light), var(--blue-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-text p {
  color: var(--text-muted);
  font-size: 18px;
  line-height: 1.7;
  margin-bottom: 48px;
  max-width: 480px;
}
@media (max-width: 1024px) { .hero-text p { margin: 0 auto 48px; } }
.hero-buttons { display: flex; flex-wrap: wrap; gap: 24px; }
.btn-primary {
  padding: 16px 40px;
  background: #fff; color: #000;
  font-weight: 700; font-size: 15px;
  border: none; border-radius: 8px; cursor: pointer;
  box-shadow: 0 8px 32px rgba(255,255,255,0.1);
  transition: background 0.2s, transform 0.15s;
}
.btn-primary:hover { background: #e5e7eb; transform: scale(1.05); }
.btn-primary:active { transform: scale(0.97); }
.btn-secondary {
  padding: 16px 40px;
  background: transparent; color: #fff;
  font-weight: 700; font-size: 15px;
  border: 2px solid rgba(255,255,255,0.2); border-radius: 8px; cursor: pointer;
  transition: background 0.2s, border-color 0.2s, transform 0.15s;
}
.btn-secondary:hover { background: rgba(255,255,255,0.05); border-color: rgba(255,255,255,0.4); transform: scale(1.05); }
.btn-secondary:active { transform: scale(0.97); }

.hero-image { position: relative; }
.glow-bg {
  position: absolute;
  inset: -80px;
  background: radial-gradient(ellipse, rgba(124,58,237,0.2), rgba(59,130,246,0.2), transparent 70%);
  border-radius: 50%;
  filter: blur(40px);
  animation: pulse 3s ease-in-out infinite;
}
@keyframes pulse { 0%,100% { opacity: 0.6; } 50% { opacity: 1; } }
.image-card {
  position: relative; z-index: 1;
  border-radius: 16px; overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: 0 32px 64px rgba(124,58,237,0.2);
}
.image-card img { width: 100%; height: auto; display: block; }
.image-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(to top, var(--bg), transparent);
  opacity: 0.4;
}
.float-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(40px);
  animation: float 4s ease-in-out infinite;
}
.orb-top { width: 128px; height: 128px; top: -40px; right: -40px; background: rgba(124,58,237,0.15); }
.orb-bottom { width: 160px; height: 160px; bottom: -40px; left: -40px; background: rgba(59,130,246,0.15); animation-delay: 1s; animation-duration: 5s; }
@keyframes float { 0%,100% { transform: translateY(0); } 50% { transform: translateY(-20px); } }

/* ── Manual ── */
.manual { padding: 128px 0 80px; }
.manual-hero {
  text-align: center;
  margin-bottom: 96px;
}
.manual-hero h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 48px;
  letter-spacing: -0.02em;
}
.manual-meta { display: flex; flex-direction: column; align-items: center; gap: 24px; }
.meta-item { display: flex; align-items: center; gap: 16px; color: #d1d5db; }
.meta-icon {
  width: 40px; height: 40px;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.download-link-box {
  display: flex; align-items: center;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border);
  border-radius: 8px; overflow: hidden;
}
.link-label {
  padding: 8px 16px;
  color: var(--text-muted); font-size: 14px;
  border-right: 1px solid var(--border);
  white-space: nowrap;
}
.download-link-box input {
  background: transparent; border: none; outline: none;
  padding: 8px 16px; font-size: 14px; color: #fff;
  width: 220px;
}
.btn-visit {
  background: var(--purple); color: #fff;
  border: none; padding: 8px 24px;
  font-size: 14px; font-weight: 600; cursor: pointer;
  transition: background 0.2s;
}
.btn-visit:hover { background: #6d28d9; }

/* ── Manual Section ── */
.manual-section { margin-bottom: 80px; }
.section-layout {
  display: flex;
  gap: 48px;
  align-items: flex-start;
}
@media (max-width: 1024px) { .section-layout { flex-direction: column; } }
.section-label { flex-shrink: 0; width: 260px; min-width: 260px; max-width: 260px; position: sticky; top: 100px; overflow: hidden; }
.section-num { font-size: 56px; font-weight: 700; color: rgba(124,58,237,0.4); line-height: 1; display: block; }
.section-label h2 { font-size: 28px; font-weight: 700; margin-top: 8px; white-space: normal; word-break: break-word; }
.section-content { flex: 1; display: flex; flex-direction: column; gap: 48px; }

.screenshot-card { position: relative; }
.screenshot-glow {
  position: absolute; inset: -4px;
  background: linear-gradient(135deg, var(--purple), var(--blue));
  border-radius: 20px;
  filter: blur(8px);
  opacity: 0.2;
  transition: opacity 0.5s;
}
.screenshot-card:hover .screenshot-glow { opacity: 0.4; }
.screenshot-inner {
  position: relative; z-index: 1;
  background: #0a0a2a;
  border-radius: 12px; overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: 0 32px 64px rgba(0,0,0,0.5);
}
.screenshot-inner img { width: 100%; height: auto; display: block; opacity: 0.9; transition: opacity 0.3s; }
.screenshot-card:hover .screenshot-inner img { opacity: 1; }

.feature-table-wrap {
  border-radius: 12px; overflow: hidden;
  border: 1px solid var(--border);
  background: rgba(255,255,255,0.03);
  backdrop-filter: blur(8px);
}
.feature-table { width: 100%; border-collapse: collapse; text-align: left; }
.feature-table thead tr { background: rgba(255,255,255,0.08); }
.feature-table th {
  padding: 16px 24px;
  font-size: 14px; font-weight: 600;
  border-bottom: 1px solid var(--border);
}
.feature-table th:nth-child(1) { width: 20%; }
.feature-table th:nth-child(2) { width: 50%; }
.feature-table th:nth-child(3) { width: 30%; }
.feature-table tbody tr { border-bottom: 1px solid rgba(255,255,255,0.04); transition: background 0.2s; }
.feature-table tbody tr:last-child { border-bottom: none; }
.feature-table tbody tr:hover { background: rgba(255,255,255,0.02); }
.feature-table td { padding: 24px; font-size: 14px; vertical-align: middle; }
.feature-table td:nth-child(1) { font-weight: 500; color: #e5e7eb; }
.feature-table td:nth-child(2) { color: var(--text-muted); line-height: 1.6; }
.thumb-wrap { border-radius: 8px; overflow: hidden; border: 1px solid var(--border); box-shadow: 0 4px 16px rgba(0,0,0,0.3); }
.thumb-wrap img { width: 100%; height: auto; display: block; }
.thumb-wrap:hover img { filter: grayscale(0); }

/* ── Footer ── */
.footer {
  border-top: 1px solid var(--border);
  padding: 48px 0;
  margin-top: auto;
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  color: var(--text-muted);
  font-size: 14px;
}
.footer-links { display: flex; gap: 32px; }
.footer-links a { color: var(--text-muted); text-decoration: none; transition: color 0.2s; }
.footer-links a:hover { color: #fff; }

/* ── Animations ── */
.fade-in-left { animation: fadeInLeft 0.8s ease-out both; }
.fade-in-right { animation: fadeInRight 1s ease-out both; }
.fade-in-up { animation: fadeInUp 0.6s ease-out both; }

@keyframes fadeInLeft {
  from { opacity: 0; transform: translateX(-50px); }
  to   { opacity: 1; transform: translateX(0); }
}
@keyframes fadeInRight {
  from { opacity: 0; transform: scale(0.85) rotate(5deg); }
  to   { opacity: 1; transform: scale(1) rotate(0); }
}
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* Page transition */
.page { animation: pageIn 0.4s ease-out both; }
@keyframes pageIn {
  from { opacity: 0; transform: translateX(20px); }
  to   { opacity: 1; transform: translateX(0); }
}

/* ── Step Blocks ── */
.step-block {
  display: flex;
  flex-direction: column;
  gap: 20px;
  padding: 32px;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border);
  border-radius: 16px;
}
.step-title {
  font-size: 18px;
  font-weight: 700;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.step-subtitle {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-muted);
  background: rgba(255,255,255,0.06);
  padding: 3px 10px;
  border-radius: 20px;
}
.step-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  color: var(--purple-light);
  background: rgba(124,58,237,0.15);
  border: 1px solid rgba(124,58,237,0.3);
  padding: 2px 8px;
  border-radius: 4px;
  margin-right: 6px;
  vertical-align: middle;
}
.step-desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
}
.step-list {
  padding-left: 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.step-list li {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
}
.step-list li strong { color: #e5e7eb; }

/* ── Substep Blocks ── */
.substep-block {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 24px;
  background: rgba(255,255,255,0.02);
  border-left: 3px solid rgba(124,58,237,0.4);
  border-radius: 0 12px 12px 0;
}
.substep-title {
  font-size: 15px;
  font-weight: 600;
  color: #e5e7eb;
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}
.substep-badge {
  font-size: 11px;
  font-weight: 500;
  color: var(--blue-light);
  background: rgba(59,130,246,0.12);
  border: 1px solid rgba(59,130,246,0.25);
  padding: 2px 8px;
  border-radius: 20px;
}

/* ── Info Row ── */
.info-row {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}
.info-label {
  flex-shrink: 0;
  font-size: 11px;
  font-weight: 600;
  color: var(--purple-light);
  background: rgba(124,58,237,0.12);
  border: 1px solid rgba(124,58,237,0.25);
  padding: 4px 10px;
  border-radius: 4px;
  white-space: nowrap;
  margin-top: 2px;
}
.info-row p {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ── Notice Box ── */
.notice-box {
  font-size: 14px;
  color: #d1d5db;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 8px;
  padding: 12px 16px;
  line-height: 1.6;
}
.notice-box--warn {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  background: rgba(234,179,8,0.06);
  border-color: rgba(234,179,8,0.2);
  color: #fde68a;
}
.notice-box--warn svg { color: #fbbf24; }

/* ── Recommend Tag ── */
.recommend-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  color: #6ee7b7;
  background: rgba(16,185,129,0.1);
  border: 1px solid rgba(16,185,129,0.25);
  padding: 2px 8px;
  border-radius: 20px;
  margin-left: 4px;
  vertical-align: middle;
}

/* ── Inline Link ── */
.inline-link {
  color: var(--blue-light);
  text-decoration: none;
  border-bottom: 1px solid rgba(147,197,253,0.3);
  transition: border-color 0.2s;
}
.inline-link:hover { border-color: var(--blue-light); }

/* ── Screenshot small variant ── */
.screenshot-card--sm .screenshot-inner { border-radius: 8px; }

/* ── Mode Cards ── */
.mode-card {
  padding: 24px;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border);
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.mode-card-header {
  display: flex;
  align-items: center;
  gap: 10px;
}
.mode-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}
.mode-dot--sync    { background: #60a5fa; box-shadow: 0 0 8px rgba(96,165,250,0.6); }
.mode-dot--dynamic { background: #f472b6; box-shadow: 0 0 8px rgba(244,114,182,0.6); }
.mode-dot--rhythm  { background: #34d399; box-shadow: 0 0 8px rgba(52,211,153,0.6); }
.mode-name {
  font-size: 15px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.05em;
}

/* ── Info Card (Section IV) ── */
.info-card {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  padding: 28px;
  background: rgba(124,58,237,0.06);
  border: 1px solid rgba(124,58,237,0.2);
  border-radius: 16px;
}
.info-card-icon {
  width: 48px; height: 48px;
  flex-shrink: 0;
  background: rgba(124,58,237,0.15);
  border: 1px solid rgba(124,58,237,0.3);
  border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  color: var(--purple-light);
}
.info-card-title {
  font-size: 15px;
  font-weight: 600;
  color: #e5e7eb;
  margin-bottom: 8px;
}
.info-card-desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ── Contact Grid (Section V) ── */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
@media (max-width: 640px) { .contact-grid { grid-template-columns: 1fr; } }
.contact-card {
  display: flex;
  gap: 16px;
  align-items: center;
  padding: 20px 24px;
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--border);
  border-radius: 12px;
  text-decoration: none;
  transition: background 0.2s, border-color 0.2s;
}
.contact-card:hover {
  background: rgba(255,255,255,0.06);
  border-color: rgba(124,58,237,0.4);
}
.contact-icon {
  width: 44px; height: 44px;
  flex-shrink: 0;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border);
  border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  color: var(--purple-light);
}
.contact-label {
  font-size: 11px;
  color: var(--text-muted);
  margin-bottom: 4px;
}
.contact-value {
  font-size: 14px;
  font-weight: 500;
  color: var(--blue-light);
  word-break: break-all;
}

/* ── Download Dropdown ── */
.download-dropdown {
  position: relative;
  display: inline-block;
}
.download-trigger {
  display: flex;
  align-items: center;
  gap: 8px;
}
.dropdown-arrow {
  transition: transform 0.25s ease;
  flex-shrink: 0;
}
.download-dropdown.open .dropdown-arrow {
  transform: rotate(180deg);
}
.download-menu {
  position: absolute;
  top: calc(100% + 10px);
  left: 0;
  min-width: 260px;
  background: #0e0e2e;
  border: 1px solid rgba(124,58,237,0.3);
  border-radius: 12px;
  box-shadow: 0 16px 48px rgba(0,0,0,0.6), 0 0 0 1px rgba(255,255,255,0.04);
  overflow: hidden;
  opacity: 0;
  transform: translateY(-8px);
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  z-index: 100;
}
.download-dropdown.open .download-menu {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
.download-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 18px;
  text-decoration: none;
  color: #fff;
  transition: background 0.15s;
  border-bottom: 1px solid rgba(255,255,255,0.05);
}
.download-item:last-child { border-bottom: none; }
.download-item:hover { background: rgba(124,58,237,0.12); }
.download-item-icon {
  width: 36px; height: 36px;
  flex-shrink: 0;
  border-radius: 8px;
  background: rgba(59,130,246,0.15);
  border: 1px solid rgba(59,130,246,0.25);
  display: flex; align-items: center; justify-content: center;
  color: var(--blue-light);
}
.download-item-icon--pdf {
  background: rgba(239,68,68,0.12);
  border-color: rgba(239,68,68,0.25);
  color: #fca5a5;
}
.download-item-info {
  display: flex;
  flex-direction: column;
  gap: 3px;
}
.download-item-name {
  font-size: 14px;
  font-weight: 600;
  color: #f3f4f6;
}
.download-item-desc {
  font-size: 12px;
  color: var(--text-muted);
}