:root {
  --bg: #0d0f1a;
  --surface: #151929;
  --border: #1f2640;
  --primary: #6c63ff;
  --accent: #00d4ff;
  --green: #00e676;
  --red: #ff1744;
  --text: #e8eaf6;
  --muted: #7986cb;
  --shadow: 0 4px 24px rgba(108, 99, 255, 0.10);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Inter", sans-serif;
  line-height: 1.6;
}

body.menu-open {
  overflow: hidden;
}

a {
  color: inherit;
}

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  background: rgba(21, 25, 41, 0.96);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
}

.nav-logo {
  font-family: "Space Grotesk", sans-serif;
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: -0.5px;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.95rem;
  transition: color 0.2s;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent);
}

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
  width: 42px;
  height: 42px;
  border-radius: 8px;
  font-size: 1.25rem;
  cursor: pointer;
}

.page {
  width: min(1120px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 4rem 0;
}

.section-title,
h1,
h2,
h3 {
  font-family: "Space Grotesk", sans-serif;
  line-height: 1.1;
  letter-spacing: 0;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

.subtitle,
.muted {
  color: var(--muted);
}

.hero {
  min-height: calc(100vh - 74px);
  display: grid;
  align-items: center;
  position: relative;
  overflow: hidden;
  isolation: isolate;
  background:
    linear-gradient(120deg, rgba(108, 99, 255, 0.28), rgba(0, 212, 255, 0.08), rgba(13, 15, 26, 0.96)),
    radial-gradient(circle at 50% 20%, rgba(0, 212, 255, 0.14), transparent 34%),
    var(--bg);
  animation: heroShift 12s ease-in-out infinite alternate;
}

.hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 8rem;
  background: linear-gradient(180deg, transparent, var(--bg));
  z-index: -1;
}

.hero-inner {
  width: min(1120px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 4rem 0 6rem;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--accent);
  border: 1px solid rgba(0, 212, 255, 0.28);
  background: rgba(21, 25, 41, 0.68);
  border-radius: 999px;
  padding: 0.45rem 0.8rem;
  font-size: 0.85rem;
  margin-bottom: 1.25rem;
}

.hero h1 {
  max-width: 760px;
  font-size: clamp(2.7rem, 8vw, 5.7rem);
  margin-bottom: 1.25rem;
}

.hero p {
  max-width: 690px;
  color: var(--text);
  font-size: 1.08rem;
}

.hero-actions,
.button-row {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 2rem;
}

.btn,
button.primary-action,
#refresh-btn,
.block-card button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-height: 44px;
  padding: 0.78rem 1.1rem;
  background: var(--primary);
  color: white;
  border: 1px solid transparent;
  border-radius: 8px;
  font-weight: 800;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.2s, background 0.2s, border-color 0.2s;
}

.btn:hover,
button.primary-action:hover,
#refresh-btn:hover,
.block-card button:hover {
  background: var(--accent);
  color: var(--bg);
  transform: translateY(-2px);
}

.btn.secondary {
  background: transparent;
  border-color: var(--border);
  color: var(--text);
}

.btn.secondary:hover {
  border-color: var(--accent);
  color: var(--bg);
}

.section-title {
  font-size: clamp(2rem, 4vw, 3rem);
  margin-bottom: 1rem;
}

.features-grid,
.prices-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.feature-card,
.price-card,
.concept-card,
.step,
.block-card,
.insight-box,
.notice-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: var(--shadow);
}

.feature-card {
  padding: 1.5rem;
}

.feature-icon {
  font-size: 2.4rem;
  margin-bottom: 0.75rem;
}

.feature-card h3,
.step h3 {
  color: var(--accent);
  margin-bottom: 0.7rem;
}

.feature-card p,
.step p {
  color: var(--muted);
  margin-bottom: 0;
}

.flow {
  display: flex;
  align-items: stretch;
  gap: 1rem;
  margin-top: 2rem;
}

.step {
  flex: 1;
  padding: 1.3rem;
}

.step-number {
  color: var(--primary);
  font-family: "Space Grotesk", sans-serif;
  font-size: 1.8rem;
  font-weight: 800;
}

.flow-arrow {
  display: grid;
  place-items: center;
  color: var(--accent);
  font-size: 1.5rem;
  min-width: 28px;
}

.footer {
  border-top: 1px solid var(--border);
  background: var(--surface);
  padding: 2rem;
  color: var(--muted);
}

.footer-inner {
  width: min(1120px, 100%);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.footer strong,
.footer a {
  color: var(--text);
}

.concepts-page,
.prices-page,
.simulator-page {
  min-height: calc(100vh - 74px);
}

.page-header {
  margin-bottom: 2.5rem;
}

.page-header h1 {
  font-size: clamp(2.4rem, 6vw, 4.6rem);
  margin-bottom: 0.75rem;
}

.concept-card {
  display: flex;
  align-items: stretch;
  gap: 0;
  overflow: hidden;
  margin-bottom: 2rem;
}

.side {
  flex: 1;
  padding: 1.5rem 2rem;
}

.side-a {
  border-right: 1px solid var(--border);
}

.side h3 {
  color: var(--accent);
  margin-bottom: 1rem;
}

.side ul {
  color: var(--text);
  line-height: 2;
  padding-left: 1.2rem;
  margin: 0;
}

.vs-badge {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 1rem;
  font-weight: 900;
  font-size: 1.2rem;
  color: var(--primary);
  background: var(--border);
}

.prices-grid {
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

.price-card {
  padding: 1.5rem;
  text-align: center;
  transition: transform 0.2s, border-color 0.2s;
}

.price-card:hover {
  transform: translateY(-4px);
  border-color: rgba(0, 212, 255, 0.42);
}

.coin-icon {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.coin-name {
  font-weight: 700;
  color: var(--text);
}

.coin-symbol {
  color: var(--muted);
  font-weight: 400;
  font-size: 0.85rem;
}

.coin-price {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--accent);
  margin: 0.5rem 0;
}

.coin-change {
  font-size: 1rem;
  font-weight: 600;
}

.coin-change.up {
  color: var(--green);
}

.coin-change.down {
  color: var(--red);
}

.loading,
.error {
  grid-column: 1 / -1;
  padding: 1.25rem;
  border: 1px solid var(--border);
  border-radius: 12px;
  color: var(--muted);
  background: var(--surface);
}

.error {
  color: var(--red);
}

.blocks-container {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 2rem;
}

.block-card {
  border: 2px solid var(--border);
  padding: 1.5rem;
  width: min(100%, 340px);
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  transition: border-color 0.3s;
}

.block-card.valid {
  border-color: var(--green);
}

.block-card.invalid {
  border-color: var(--red);
}

.block-card label {
  color: var(--muted);
  font-size: 0.8rem;
  text-transform: uppercase;
  font-weight: 800;
}

.block-card input {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 6px;
  padding: 0.6rem 0.75rem;
  font-size: 0.85rem;
  font-family: "Courier New", monospace;
  width: 100%;
}

.block-card input[readonly] {
  color: var(--muted);
}

.status {
  font-size: 0.9rem;
  font-weight: 700;
  padding: 0.4rem 0;
}

.status.valid {
  color: var(--green);
}

.status.invalid {
  color: var(--red);
}

.chain-arrow {
  font-size: 2.5rem;
  color: var(--muted);
}

.insight-box {
  border-left: 4px solid var(--primary);
  padding: 1rem 1.5rem;
  margin-top: 2rem;
  color: var(--text);
  max-width: 760px;
  margin-inline: auto;
}

.notice-box {
  padding: 1rem 1.25rem;
  color: var(--muted);
  margin-top: 1.5rem;
}

@keyframes heroShift {
  0% {
    background-position: 0% 50%;
  }

  100% {
    background-position: 100% 50%;
  }
}

@media (max-width: 768px) {
  .navbar {
    padding: 0.85rem 1rem;
  }

  .nav-toggle {
    display: inline-grid;
    place-items: center;
  }

  .nav-links {
    position: fixed;
    inset: 70px 1rem auto 1rem;
    display: none;
    flex-direction: column;
    gap: 0;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    box-shadow: var(--shadow);
    overflow: hidden;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links a {
    display: block;
    padding: 1rem;
    border-bottom: 1px solid var(--border);
  }

  .nav-links li:last-child a {
    border-bottom: 0;
  }

  .hero {
    min-height: auto;
  }

  .hero-inner,
  .page {
    padding: 3rem 0;
  }

  .hero-actions,
  .button-row {
    flex-direction: column;
  }

  .btn,
  button.primary-action,
  #refresh-btn {
    width: 100%;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .flow {
    flex-direction: column;
  }

  .flow-arrow {
    transform: rotate(90deg);
  }

  .concept-card {
    flex-direction: column;
  }

  .side-a {
    border-right: 0;
    border-bottom: 1px solid var(--border);
  }

  .vs-badge {
    min-height: 46px;
  }

  .blocks-container {
    align-items: stretch;
  }

  .chain-arrow {
    width: 100%;
    text-align: center;
    transform: rotate(90deg);
  }

  .footer-inner {
    display: block;
  }
}