:root {
  --bg: #070c18;
  --bg-elevated: #0d1529;
  --bg-card: rgba(15, 25, 50, 0.65);
  --text: #e8edf7;
  --muted: #8a9bb5;
  --accent: #059669;
  --accent-hover: #10b981;
  --accent-blue: #3b82f6;
  --accent-purple: #8b5cf6;
  --border: rgba(148, 163, 184, 0.12);
  --border-glow: rgba(16, 185, 129, 0.25);
  --radius: 16px;
  --font: ui-sans-serif, system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --wrap: min(1000px, 100% - 2.5rem);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent-hover);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.wrap {
  width: var(--wrap);
  margin-inline: auto;
}

/* ── Animations ── */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes shimmer {
  0% { background-position: -200% center; }
  100% { background-position: 200% center; }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

@keyframes pulseGlow {
  0%, 100% { opacity: 0.6; }
  50% { opacity: 1; }
}

@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

/* ── Header ── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid var(--border);
  background: rgba(7, 12, 24, 0.75);
  backdrop-filter: blur(20px) saturate(1.4);
  -webkit-backdrop-filter: blur(20px) saturate(1.4);
}

.header-inner {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 0.75rem 1rem;
  padding: 0.85rem 0;
}

@media (max-width: 720px) {
  .header-inner {
    grid-template-columns: 1fr auto;
  }

  .logo {
    grid-column: 1;
  }

  .lang-pick {
    grid-column: 2;
    justify-self: end;
  }

  .nav {
    grid-column: 1 / -1;
    justify-content: center;
    flex-wrap: wrap;
    row-gap: 0.35rem;
  }
}

.lang-pick {
  display: flex;
  gap: 0.35rem;
  flex-shrink: 0;
}

.lang-pick button {
  border: 1px solid var(--border);
  background: rgba(15, 25, 50, 0.5);
  color: var(--muted);
  padding: 0.35rem 0.65rem;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  font-family: inherit;
  transition: all 0.2s ease;
}

.lang-pick button.is-on {
  background: linear-gradient(135deg, var(--accent), var(--accent-hover));
  border-color: transparent;
  color: #fff;
  box-shadow: 0 0 12px rgba(16, 185, 129, 0.3);
}

.lang-pick button:hover:not(.is-on) {
  border-color: var(--muted);
  color: var(--text);
  background: rgba(15, 25, 50, 0.8);
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
  color: var(--text);
  text-decoration: none;
}

.logo:hover {
  text-decoration: none;
}

.logo-mark {
  width: 36px;
  height: 36px;
  border-radius: 9px;
  object-fit: cover;
  flex-shrink: 0;
}

.logo-wordmark {
  font-variant-numeric: tabular-nums;
  color: var(--accent-hover);
}

.logo-prefix {
  color: var(--text);
}

.nav {
  display: flex;
  gap: 1.5rem;
  justify-self: center;
}

.nav a {
  color: var(--muted);
  font-size: 0.92rem;
  text-decoration: none;
  transition: color 0.2s ease;
  position: relative;
}

.nav a::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-hover), var(--accent-blue));
  border-radius: 1px;
  transition: width 0.25s ease;
}

.nav a:hover {
  color: var(--text);
  text-decoration: none;
}

.nav a:hover::after {
  width: 100%;
}

/* ── Hero ── */
.hero {
  position: relative;
  padding: clamp(4rem, 10vw, 6rem) 0 clamp(3rem, 7vw, 4rem);
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 50% -10%, rgba(16, 185, 129, 0.12), transparent 60%),
    radial-gradient(ellipse 60% 50% at 80% 20%, rgba(59, 130, 246, 0.08), transparent 50%),
    radial-gradient(ellipse 50% 40% at 10% 60%, rgba(139, 92, 246, 0.06), transparent 50%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  z-index: 1;
  animation: fadeUp 0.8s ease-out;
}

.eyebrow {
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 1rem;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: rgba(15, 25, 50, 0.5);
  backdrop-filter: blur(8px);
}

.eyebrow-link {
  color: var(--accent-hover);
  text-decoration: none;
  user-select: all;
}

.eyebrow-link:hover {
  text-decoration: underline;
}

.hero h1 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  line-height: 1.3;
  margin: 0 0 1.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, #ffffff 0%, #e8edf7 40%, var(--accent-hover) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.intro {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 2.5rem;
}

.intro .lead {
  margin: 0;
}

.lead {
  margin: 0 0 1.75rem;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.85;
}

.product-name {
  color: var(--text);
  font-weight: 600;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.6rem 1.4rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.9rem;
  border: 1px solid transparent;
  text-decoration: none;
  transition: all 0.25s ease;
  cursor: pointer;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-hover));
  color: #fff;
  box-shadow: 0 0 20px rgba(16, 185, 129, 0.2), 0 4px 12px rgba(0, 0, 0, 0.3);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--accent-hover), #34d399);
  box-shadow: 0 0 30px rgba(16, 185, 129, 0.35), 0 6px 16px rgba(0, 0, 0, 0.3);
  transform: translateY(-1px);
  text-decoration: none;
}

.btn-ghost {
  border-color: var(--border);
  color: var(--text);
  background: rgba(15, 25, 50, 0.4);
  backdrop-filter: blur(8px);
}

.btn-ghost:hover {
  border-color: var(--accent-hover);
  color: var(--accent-hover);
  background: rgba(16, 185, 129, 0.06);
  text-decoration: none;
}

.hero-glow {
  position: absolute;
  inset: -30% -10% auto 35%;
  height: 80%;
  background: radial-gradient(closest-side, rgba(16, 185, 129, 0.15), transparent 70%);
  pointer-events: none;
  animation: pulseGlow 6s ease-in-out infinite;
}

/* ── Mesh background ── */
.hero-mesh {
  position: absolute;
  bottom: -50%;
  right: -20%;
  width: 80%;
  height: 100%;
  background: radial-gradient(closest-side, rgba(59, 130, 246, 0.08), transparent 70%);
  pointer-events: none;
}

/* ── Sections ── */
.section {
  padding: clamp(3rem, 7vw, 4.5rem) 0;
  position: relative;
}

.section-alt {
  background: var(--bg-elevated);
  border-block: 1px solid var(--border);
}

.section-title {
  font-size: clamp(1.35rem, 2.8vw, 1.75rem);
  margin: 0 0 0.6rem;
  letter-spacing: -0.02em;
  font-weight: 700;
}

.section-sub {
  margin: 0 0 2rem;
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ── Cards ── */
.grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1rem;
}

@media (min-width: 720px) {
  .cards {
    grid-template-columns: repeat(3, 1fr);
  }

  .features {
    grid-template-columns: repeat(3, 1fr);
  }
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.35rem 1.5rem;
  backdrop-filter: blur(12px);
  transition: all 0.3s ease;
}

.card:hover {
  border-color: var(--border-glow);
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2), 0 0 20px rgba(16, 185, 129, 0.06);
}

.card h3 {
  margin: 0 0 0.4rem;
  font-size: 1.02rem;
}

.card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.65;
}

.cards-core {
  gap: 0.85rem;
}

@media (min-width: 800px) {
  .cards-core {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .cards-core .card-core:nth-child(5) {
    grid-column: 1 / -1;
    max-width: 100%;
    width: 100%;
  }
}

.card-core {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0 1rem;
  align-items: start;
}

.cap-n {
  width: 2.2rem;
  height: 2.2rem;
  border-radius: 999px;
  background: linear-gradient(145deg, var(--accent-hover), var(--accent));
  color: #fff;
  font-weight: 700;
  font-size: 0.88rem;
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
  flex-shrink: 0;
  margin-top: 0.1rem;
  box-shadow: 0 0 14px rgba(16, 185, 129, 0.3);
}

.card-core-body h3 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
}

.card-core-body p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.6;
}

.features li {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1.35rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  transition: all 0.3s ease;
}

.features li:hover {
  border-color: var(--border-glow);
}

.features strong {
  font-size: 1.02rem;
}

.features span {
  color: var(--muted);
  font-size: 0.92rem;
}

/* ── Contact ── */
.contact-inner {
  text-align: center;
}

.contact-inner .section-title,
.contact-inner .section-sub {
  margin-inline: auto;
}

.contact-box {
  margin-top: 1.25rem;
  padding: 1.5rem 1.5rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  max-width: 30rem;
  margin-inline: auto;
  text-align: left;
  transition: border-color 0.3s ease;
}

.contact-box:hover {
  border-color: var(--border-glow);
}

.contact-box p {
  margin: 0 0 0.65rem;
  font-size: 0.95rem;
}

.contact-box p:last-child {
  margin-bottom: 0;
}

.hint {
  font-size: 0.82rem;
  color: var(--muted);
  margin-top: 0.85rem !important;
  padding-top: 0.85rem;
  border-top: 1px dashed var(--border);
}

/* ── Message Form ── */
.msg-form {
  max-width: 30rem;
  margin: 1.25rem auto 0;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  text-align: left;
}

.msg-form input,
.msg-form textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: rgba(7, 12, 24, 0.6);
  color: var(--text);
  font-family: inherit;
  font-size: 0.92rem;
  line-height: 1.5;
  outline: none;
  transition: all 0.25s ease;
  backdrop-filter: blur(8px);
}

.msg-form input::placeholder,
.msg-form textarea::placeholder {
  color: rgba(138, 155, 181, 0.45);
}

.msg-form input:focus,
.msg-form textarea:focus {
  border-color: var(--accent-hover);
  box-shadow: 0 0 16px rgba(16, 185, 129, 0.12);
}

.msg-form textarea {
  resize: vertical;
  min-height: 5rem;
}

.btn-submit {
  align-self: flex-start;
  padding: 0.65rem 1.85rem;
  font-size: 0.9rem;
  cursor: pointer;
  border: none;
  font-family: inherit;
}

.form-status {
  text-align: center;
  font-size: 0.85rem;
  color: var(--accent-hover);
  margin: 0.5rem 0 0;
  min-height: 1.2em;
}

/* ── Footer ── */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 1.5rem 0 1.75rem;
  color: var(--muted);
  font-size: 0.85rem;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.footer-links a {
  color: var(--muted);
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: var(--accent-hover);
}

/* ── Download + Guide block ── */
#guides {
  scroll-margin-top: 5.5rem;
}

.hero-download-block {
  margin-bottom: 1.25rem;
}

.download-panel {
  padding: 1.35rem 1.5rem;
  border-radius: var(--radius);
  border: 1px solid rgba(16, 185, 129, 0.2);
  background: linear-gradient(165deg, rgba(16, 185, 129, 0.1), rgba(5, 150, 105, 0.03));
  backdrop-filter: blur(12px);
  margin-bottom: 0.85rem;
  position: relative;
  overflow: hidden;
}

.download-panel::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(16, 185, 129, 0.4), transparent);
}

.download-label {
  margin: 0 0 0.65rem;
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
}

.btn-disabled {
  opacity: 0.45;
  pointer-events: none;
  cursor: default;
}

.download-hint {
  margin: 0.6rem 0 0.55rem;
  font-size: 0.82rem;
  color: var(--muted);
  line-height: 1.45;
}

.download-subrow {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.btn-download-sub {
  flex: 1;
  min-width: 8rem;
  text-align: center;
  padding: 0.5rem 0.75rem;
  border-radius: 10px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text) !important;
  background: rgba(15, 25, 50, 0.6);
  border: 1px solid var(--border);
  text-decoration: none;
  transition: all 0.25s ease;
}

.btn-download-sub:hover {
  border-color: var(--accent-hover);
  background: rgba(16, 185, 129, 0.08);
  text-decoration: none;
}

.guide-link-row {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

@media (min-width: 520px) {
  .guide-link-row {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .guide-link-row .btn-guide {
    flex: 1;
    min-width: 12rem;
  }
}

.btn-guide {
  text-align: center;
  padding: 0.7rem 1.1rem;
  border-radius: 10px;
  font-weight: 600;
  font-size: 0.88rem;
  border: 1px solid var(--border);
  background: rgba(15, 25, 50, 0.5);
  color: var(--text) !important;
  text-decoration: none;
  transition: all 0.25s ease;
}

.btn-guide:hover {
  border-color: var(--accent-hover);
  color: var(--accent-hover) !important;
  background: rgba(16, 185, 129, 0.06);
  text-decoration: none;
}

.guides-note {
  margin: 0.5rem 0 0;
  font-size: 0.8rem;
  color: var(--muted);
  line-height: 1.45;
}

/* ── Scroll reveal ── */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── Grid decoration ── */
.grid-bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(148, 163, 184, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(148, 163, 184, 0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 70% 50% at 50% 30%, black 20%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 70% 50% at 50% 30%, black 20%, transparent 70%);
}

/* ── Top gradient line ── */
.top-line {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent-hover), var(--accent-blue), var(--accent-purple), transparent);
  background-size: 200% 100%;
  animation: gradientShift 4s ease infinite;
  z-index: 30;
}