/* ==========================================================================
   MDSS 梦迪云网 (mdss.homes) — Pure Native CSS Stylesheet
   Zero external frameworks, zero JS dependencies, GPU-accelerated dynamic bg
   ========================================================================== */

:root {
  --bg-base: #050814;
  --bg-surface: rgba(12, 19, 38, 0.72);
  --bg-surface-strong: rgba(15, 23, 46, 0.9);
  --bg-card-hover: rgba(20, 31, 60, 0.88);
  --border-subtle: rgba(148, 163, 184, 0.16);
  --border-glow: rgba(0, 229, 255, 0.42);
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --accent-cyan: #00e5ff;
  --accent-teal: #2dd4bf;
  --accent-blue: #3b82f6;
  --accent-purple: #8b5cf6;
  --accent-emerald: #10b981;
  --accent-amber: #f59e0b;
  --gradient-brand: linear-gradient(135deg, #00e5ff 0%, #3b82f6 52%, #8b5cf6 100%);
  --gradient-cta: linear-gradient(135deg, #06b6d4 0%, #3b82f6 55%, #7c3aed 100%);
  --shadow-card: 0 18px 45px -18px rgba(2, 6, 23, 0.85);
  --shadow-glow: 0 10px 35px -8px rgba(0, 229, 255, 0.35);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 22px;
  --radius-xl: 28px;
  --container-max: 1260px;
  --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-base);
  color: var(--text-primary);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  line-height: 1.7;
  color: var(--text-primary);
  background: transparent;
  overflow-x: hidden;
  min-height: 100vh;
}

a {
  color: inherit;
  text-decoration: none;
}

img,
svg {
  display: block;
  max-width: 100%;
}

ul,
ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

h1,
h2,
h3,
h4,
p {
  margin: 0;
}

:focus-visible {
  outline: 2px solid var(--accent-cyan);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 200;
  padding: 0.75rem 1.25rem;
  background: var(--accent-cyan);
  color: #04101f;
  font-weight: 700;
  border-radius: 0 0 var(--radius-sm) 0;
}

.skip-link:focus {
  left: 0;
}

/* ==========================================================================
   Dynamic Animated Background (Pure CSS GPU-Accelerated)
   ========================================================================== */

.ambient-stage {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
  background: radial-gradient(circle at 50% 0%, #0b1634 0%, #050814 58%, #03050d 100%);
}

/* Distant dense multi-color twinkling star dust layers */
.ambient-stage::before,
.ambient-stage::after {
  content: "";
  position: absolute;
  inset: -120px;
  pointer-events: none;
}

.ambient-stage::before {
  background-image:
    radial-gradient(1.5px 1.5px at 24px 36px, rgba(255, 255, 255, 0.85), transparent),
    radial-gradient(1.2px 1.2px at 92px 144px, rgba(125, 211, 252, 0.8), transparent),
    radial-gradient(1.6px 1.6px at 176px 64px, rgba(253, 230, 138, 0.75), transparent),
    radial-gradient(1.2px 1.2px at 234px 192px, rgba(221, 214, 254, 0.85), transparent),
    radial-gradient(1.5px 1.5px at 310px 118px, rgba(94, 234, 212, 0.8), transparent),
    radial-gradient(1px 1px at 54px 210px, rgba(255, 255, 255, 0.65), transparent);
  background-size: 340px 260px;
  animation: starDustFloatA 48s linear infinite, starShimmer 6s ease-in-out infinite alternate;
}

.ambient-stage::after {
  background-image:
    radial-gradient(1.8px 1.8px at 44px 82px, rgba(255, 255, 255, 0.75), transparent),
    radial-gradient(1.4px 1.4px at 138px 28px, rgba(196, 181, 253, 0.85), transparent),
    radial-gradient(1.6px 1.6px at 212px 168px, rgba(103, 232, 249, 0.85), transparent),
    radial-gradient(1.3px 1.3px at 292px 52px, rgba(253, 224, 71, 0.7), transparent),
    radial-gradient(1.2px 1.2px at 360px 218px, rgba(255, 255, 255, 0.6), transparent);
  background-size: 410px 290px;
  animation: starDustFloatB 68s linear infinite, starShimmer 8s ease-in-out infinite alternate-reverse;
}

.cyber-grid {
  position: absolute;
  inset: -120px;
  background-image:
    linear-gradient(to right, rgba(56, 189, 248, 0.055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(56, 189, 248, 0.055) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 80% 70% at 50% 35%, #000 35%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 80% 70% at 50% 35%, #000 35%, transparent 100%);
  animation: gridDrift 28s linear infinite;
}

.aurora-orb {
  position: absolute;
  border-radius: 999px;
  filter: blur(85px);
  opacity: 0.45;
  will-change: transform, opacity;
}

.aurora-orb--cyan {
  width: 56vw;
  height: 46vw;
  max-width: 780px;
  max-height: 640px;
  top: -14%;
  left: -8%;
  background: radial-gradient(circle, rgba(0, 229, 255, 0.42) 0%, rgba(59, 130, 246, 0.12) 60%, transparent 78%);
  animation: auroraFloatA 22s ease-in-out infinite alternate;
}

.aurora-orb--indigo {
  width: 52vw;
  height: 48vw;
  max-width: 760px;
  max-height: 700px;
  top: 18%;
  right: -12%;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.4) 0%, rgba(59, 130, 246, 0.14) 58%, transparent 78%);
  animation: auroraFloatB 26s ease-in-out infinite alternate;
}

.aurora-orb--teal {
  width: 48vw;
  height: 36vw;
  max-width: 680px;
  max-height: 520px;
  bottom: -10%;
  left: 22%;
  background: radial-gradient(circle, rgba(45, 212, 191, 0.28) 0%, rgba(16, 185, 129, 0.08) 62%, transparent 80%);
  animation: auroraFloatC 20s ease-in-out infinite alternate;
}

.orbital-ring {
  position: absolute;
  top: 12%;
  left: 50%;
  width: 960px;
  height: 960px;
  margin-left: -480px;
  border-radius: 50%;
  border: 1px dashed rgba(56, 189, 248, 0.12);
  box-shadow: inset 0 0 80px rgba(0, 229, 255, 0.04);
  animation: orbitRotate 60s linear infinite;
}

.orbital-ring::after {
  content: "";
  position: absolute;
  top: -4px;
  left: 50%;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-cyan);
  box-shadow: 0 0 18px 4px rgba(0, 229, 255, 0.8);
}

.light-beam {
  position: absolute;
  top: -30%;
  left: -20%;
  width: 140%;
  height: 220px;
  background: linear-gradient(90deg, transparent 0%, rgba(0, 229, 255, 0.08) 35%, rgba(139, 92, 246, 0.1) 65%, transparent 100%);
  transform: rotate(-16deg);
  filter: blur(28px);
  animation: beamSweep 14s ease-in-out infinite;
}

.star-field {
  position: absolute;
  inset: 0;
}

/* Type 1: Glowing Orb Stars */
.star-node {
  position: absolute;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: #7dd3fc;
  box-shadow: 0 0 14px 2px rgba(0, 229, 255, 0.7);
  animation: nodePulse 4.8s ease-in-out infinite;
}

.star-node:nth-child(1) { top: 14%; left: 10%; animation-delay: 0s; }
.star-node:nth-child(2) { top: 24%; left: 82%; width: 5px; height: 5px; animation-delay: 1.1s; background: #c4b5fd; box-shadow: 0 0 16px 3px rgba(196, 181, 253, 0.75); }
.star-node:nth-child(3) { top: 46%; left: 18%; animation-delay: 2.2s; }
.star-node:nth-child(4) { top: 58%; left: 88%; width: 5px; height: 5px; animation-delay: 0.7s; background: #5eead4; box-shadow: 0 0 16px 3px rgba(94, 234, 212, 0.7); }
.star-node:nth-child(5) { top: 74%; left: 14%; animation-delay: 1.8s; background: #fde68a; box-shadow: 0 0 14px 2px rgba(253, 230, 138, 0.7); }
.star-node:nth-child(6) { top: 84%; left: 74%; animation-delay: 2.9s; }
.star-node:nth-child(7) { top: 36%; left: 54%; width: 3px; height: 3px; animation-delay: 3.4s; background: #5eead4; }
.star-node:nth-child(8) { top: 9%; left: 61%; width: 5px; height: 5px; animation-delay: 1.5s; background: #ffffff; box-shadow: 0 0 18px 3px rgba(255, 255, 255, 0.8); }

/* Type 2: 4-Point Cross Sparkle Stars (四角闪耀星芒) */
.star-sparkle {
  position: absolute;
  width: 16px;
  height: 16px;
  background: #e0f2fe;
  clip-path: polygon(50% 0%, 60% 40%, 100% 50%, 60% 60%, 50% 100%, 40% 60%, 0% 50%, 40% 40%);
  filter: drop-shadow(0 0 8px rgba(0, 229, 255, 0.85));
  animation: sparkleTwinkle 4.5s ease-in-out infinite;
}

.star-sparkle--sm { width: 11px; height: 11px; }
.star-sparkle--lg { width: 22px; height: 22px; }
.star-sparkle--gold { background: #fef08a; filter: drop-shadow(0 0 9px rgba(253, 224, 71, 0.85)); }
.star-sparkle--violet { background: #e9d5ff; filter: drop-shadow(0 0 9px rgba(167, 139, 250, 0.85)); }
.star-sparkle--teal { background: #99f6e4; filter: drop-shadow(0 0 9px rgba(45, 212, 191, 0.85)); }

/* Type 3: 5-Point Classic Stars (五角星) */
.star-five {
  position: absolute;
  width: 14px;
  height: 14px;
  background: #fde68a;
  clip-path: polygon(50% 0%, 61% 35%, 98% 35%, 68% 57%, 79% 91%, 50% 70%, 21% 91%, 32% 57%, 2% 35%, 39% 35%);
  filter: drop-shadow(0 0 7px rgba(253, 230, 138, 0.75));
  animation: starSpinTwinkle 9s ease-in-out infinite;
}

.star-five--cyan { background: #7dd3fc; filter: drop-shadow(0 0 7px rgba(56, 189, 248, 0.8)); }
.star-five--violet { background: #ddd6fe; filter: drop-shadow(0 0 7px rgba(167, 139, 250, 0.8)); }
.star-five--sm { width: 10px; height: 10px; }
.star-five--lg { width: 19px; height: 19px; }

/* Type 4: 6-Point Hexagram & Diamond Stars (六芒星与棱形星) */
.star-hex {
  position: absolute;
  width: 15px;
  height: 15px;
  background: #a5f3fc;
  clip-path: polygon(50% 0%, 64% 25%, 93% 25%, 78% 50%, 93% 75%, 64% 75%, 50% 100%, 36% 75%, 7% 75%, 22% 50%, 7% 25%, 36% 25%);
  filter: drop-shadow(0 0 8px rgba(34, 211, 238, 0.8));
  animation: starSpinReverse 12s linear infinite;
}

.star-diamond {
  position: absolute;
  width: 10px;
  height: 14px;
  background: #f8fafc;
  clip-path: polygon(50% 0%, 100% 50%, 50% 100%, 0% 50%);
  filter: drop-shadow(0 0 6px rgba(255, 255, 255, 0.78));
  animation: nodePulse 5.6s ease-in-out infinite;
}

/* Type 5: Shooting Stars / Meteors (动态流星) */
.star-meteor {
  position: absolute;
  width: 150px;
  height: 2px;
  background: linear-gradient(90deg, rgba(255, 255, 255, 0) 0%, rgba(125, 211, 252, 0.55) 65%, #ffffff 100%);
  border-radius: 999px;
  opacity: 0;
  transform: rotate(28deg);
  filter: drop-shadow(0 0 6px rgba(0, 229, 255, 0.9));
  animation: meteorFly 8s linear infinite;
}

.star-meteor::after {
  content: "";
  position: absolute;
  right: -2px;
  top: -2px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #ffffff;
  box-shadow: 0 0 12px 3px rgba(0, 229, 255, 0.95);
}

/* Position & Timing Variations for Rich Sky */
.sp-1  { top: 11%; left: 22%; animation-delay: 0.2s; }
.sp-2  { top: 18%; left: 75%; animation-delay: 1.6s; }
.sp-3  { top: 32%; left: 8%;  animation-delay: 2.8s; }
.sp-4  { top: 41%; left: 91%; animation-delay: 0.9s; }
.sp-5  { top: 64%; left: 6%;  animation-delay: 3.4s; }
.sp-6  { top: 76%; left: 86%; animation-delay: 1.9s; }
.sp-7  { top: 89%; left: 32%; animation-delay: 2.3s; }
.sp-8  { top: 22%; left: 17%; animation-delay: 4.1s; }

.sf-1  { top: 15%; left: 27%; animation-delay: 0.5s; }
.sf-2  { top: 21%; left: 90%; animation-delay: 2.1s; }
.sf-3  { top: 51%; left: 7%;  animation-delay: 3.7s; }
.sf-4  { top: 68%; left: 79%; animation-delay: 1.4s; }
.sf-5  { top: 86%; left: 58%; animation-delay: 4.6s; }
.sf-6  { top: 13%; left: 71%; animation-delay: 2.9s; }

.sh-1  { top: 29%; left: 67%; animation-delay: 0s; }
.sh-2  { top: 55%; left: 29%; animation-delay: 3s; background: #ddd6fe; }
.sh-3  { top: 79%; left: 45%; animation-delay: 6s; background: #fef08a; }

.sd-1  { top: 19%; left: 15%; animation-delay: 0.8s; }
.sd-2  { top: 43%; left: 72%; animation-delay: 2.6s; background: #a5f3fc; }
.sd-3  { top: 63%; left: 93%; animation-delay: 1.3s; background: #fde68a; }
.sd-4  { top: 91%; left: 18%; animation-delay: 3.9s; background: #e9d5ff; }

.sm-1  { top: 12%; left: 18%; animation-duration: 7.5s; animation-delay: 0.5s; }
.sm-2  { top: 26%; left: 58%; animation-duration: 9.5s; animation-delay: 3.8s; }
.sm-3  { top: 52%; left: 32%; animation-duration: 11s; animation-delay: 6.4s; }

@keyframes gridDrift {
  0% { transform: translate3d(0, 0, 0); }
  100% { transform: translate3d(64px, 64px, 0); }
}

@keyframes starDustFloatA {
  0% { transform: translate3d(0, 0, 0); }
  100% { transform: translate3d(-170px, -130px, 0); }
}

@keyframes starDustFloatB {
  0% { transform: translate3d(0, 0, 0); }
  100% { transform: translate3d(180px, -110px, 0); }
}

@keyframes starShimmer {
  0% { opacity: 0.52; }
  100% { opacity: 0.92; }
}

@keyframes auroraFloatA {
  0% { transform: translate3d(0, 0, 0) scale(1); }
  100% { transform: translate3d(8vw, 6vh, 0) scale(1.12); }
}

@keyframes auroraFloatB {
  0% { transform: translate3d(0, 0, 0) scale(1); }
  100% { transform: translate3d(-7vw, -5vh, 0) scale(1.1); }
}

@keyframes auroraFloatC {
  0% { transform: translate3d(0, 0, 0) scale(0.96); }
  100% { transform: translate3d(5vw, -6vh, 0) scale(1.08); }
}

@keyframes orbitRotate {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

@keyframes beamSweep {
  0%, 100% { transform: translate3d(-8%, -6%, 0) rotate(-16deg); opacity: 0.35; }
  50% { transform: translate3d(10%, 35vh, 0) rotate(-16deg); opacity: 0.85; }
}

@keyframes nodePulse {
  0%, 100% { transform: scale(0.8); opacity: 0.35; }
  50% { transform: scale(1.55); opacity: 0.98; }
}

@keyframes sparkleTwinkle {
  0%, 100% { transform: scale(0.55) rotate(0deg); opacity: 0.3; }
  50% { transform: scale(1.2) rotate(22deg); opacity: 0.95; }
}

@keyframes starSpinTwinkle {
  0% { transform: scale(0.75) rotate(0deg); opacity: 0.45; }
  50% { transform: scale(1.18) rotate(180deg); opacity: 0.95; }
  100% { transform: scale(0.75) rotate(360deg); opacity: 0.45; }
}

@keyframes starSpinReverse {
  0% { transform: rotate(360deg) scale(0.9); opacity: 0.55; }
  50% { transform: rotate(180deg) scale(1.15); opacity: 0.9; }
  100% { transform: rotate(0deg) scale(0.9); opacity: 0.55; }
}

@keyframes meteorFly {
  0% { transform: translate3d(-120px, -70px, 0) rotate(28deg) scaleX(0.6); opacity: 0; }
  6% { opacity: 0.95; }
  22% { transform: translate3d(380px, 210px, 0) rotate(28deg) scaleX(1.1); opacity: 0; }
  100% { transform: translate3d(380px, 210px, 0) rotate(28deg) scaleX(1); opacity: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .ambient-stage::before,
  .ambient-stage::after,
  .cyber-grid,
  .aurora-orb,
  .orbital-ring,
  .light-beam,
  .star-node,
  .star-sparkle,
  .star-five,
  .star-hex,
  .star-diamond,
  .star-meteor {
    animation: none;
  }
}

/* ==========================================================================
   Layout Helpers & Containers
   ========================================================================== */

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.section {
  padding: 4.75rem 0;
  scroll-margin-top: 84px;
}

.section--compact {
  padding: 3.25rem 0;
}

.section-head {
  text-align: center;
  max-width: 780px;
  margin: 0 auto 3rem;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.32rem 0.9rem;
  border-radius: 999px;
  background: rgba(0, 229, 255, 0.09);
  border: 1px solid rgba(0, 229, 255, 0.28);
  color: var(--accent-cyan);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  margin-bottom: 1rem;
}

.section-title {
  font-size: clamp(1.65rem, 3.2vw, 2.5rem);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.015em;
  margin-bottom: 0.85rem;
}

.section-desc {
  color: var(--text-secondary);
  font-size: 1.02rem;
  line-height: 1.75;
}

.text-gradient {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ==========================================================================
   Buttons & CTA Links
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.78rem 1.55rem;
  border-radius: 12px;
  font-weight: 700;
  font-size: 0.96rem;
  line-height: 1.2;
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease, background 0.22s ease;
  cursor: pointer;
  white-space: nowrap;
}

.btn--primary {
  background: var(--gradient-cta);
  color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.18);
  box-shadow: var(--shadow-glow);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 36px -6px rgba(0, 229, 255, 0.52);
}

.btn--secondary {
  background: rgba(15, 23, 46, 0.85);
  color: var(--text-primary);
  border: 1px solid rgba(148, 163, 184, 0.3);
}

.btn--secondary:hover {
  transform: translateY(-2px);
  border-color: var(--accent-cyan);
  background: rgba(20, 34, 66, 0.95);
}

.btn--sm {
  padding: 0.56rem 1.12rem;
  font-size: 0.88rem;
  border-radius: 10px;
}

.btn--lg {
  padding: 0.95rem 2rem;
  font-size: 1.05rem;
}

.btn--full {
  width: 100%;
}

/* ==========================================================================
   Sticky Header with Top-Left Logo
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(5, 8, 20, 0.78);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border-bottom: 1px solid rgba(148, 163, 184, 0.14);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
  min-height: 72px;
}

.brand-logo {
  display: inline-flex;
  align-items: center;
  gap: 0.72rem;
  flex-shrink: 0;
}

.brand-logo__mark {
  width: 42px;
  height: 42px;
  flex-shrink: 0;
  border-radius: 50%;
  object-fit: cover;
}

.brand-logo__text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand-logo__name {
  font-size: 1.12rem;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--text-primary);
}

.brand-logo__name span {
  color: var(--accent-cyan);
}

.brand-logo__sub {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  text-transform: uppercase;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.main-nav a {
  padding: 0.45rem 0.78rem;
  border-radius: 9px;
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.18s ease, background 0.18s ease;
}

.main-nav a:hover {
  color: var(--text-primary);
  background: rgba(56, 189, 248, 0.1);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

/* Pure CSS Mobile Nav via <details> */
.mobile-nav {
  display: none;
  position: relative;
}

.mobile-nav summary {
  list-style: none;
  cursor: pointer;
  padding: 0.48rem 0.85rem;
  border-radius: 10px;
  border: 1px solid var(--border-subtle);
  background: rgba(15, 23, 46, 0.85);
  color: var(--text-primary);
  font-size: 0.88rem;
  font-weight: 600;
  user-select: none;
}

.mobile-nav summary::-webkit-details-marker {
  display: none;
}

.mobile-nav__panel {
  position: absolute;
  right: 0;
  top: calc(100% + 10px);
  width: 240px;
  padding: 0.75rem;
  border-radius: var(--radius-md);
  background: rgba(9, 14, 30, 0.96);
  border: 1px solid rgba(56, 189, 248, 0.28);
  box-shadow: 0 24px 50px rgba(0, 0, 0, 0.75);
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.mobile-nav__panel a {
  padding: 0.58rem 0.75rem;
  border-radius: 8px;
  color: var(--text-secondary);
  font-size: 0.92rem;
}

.mobile-nav__panel a:hover {
  background: rgba(56, 189, 248, 0.12);
  color: var(--text-primary);
}

/* ==========================================================================
   Hero Section
   ========================================================================== */

.hero {
  padding: 4.5rem 0 3.5rem;
}

.hero-centered {
  max-width: 1080px;
  margin: 0 auto;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.4rem 0.95rem;
  border-radius: 999px;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.35);
  color: #6ee7b7;
  font-size: 0.84rem;
  font-weight: 600;
  margin-bottom: 1.25rem;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #34d399;
  box-shadow: 0 0 12px #34d399;
  animation: nodePulse 2.4s ease-in-out infinite;
}

.hero-title {
  font-size: clamp(1.75rem, 3.25vw, 2.95rem);
  font-weight: 900;
  line-height: 1.24;
  letter-spacing: -0.02em;
  margin-bottom: 1.25rem;
}

@media (min-width: 960px) {
  .hero-line {
    white-space: nowrap;
  }
}

.hero-subtitle {
  font-size: 1.07rem;
  color: var(--text-secondary);
  line-height: 1.82;
  margin: 0 auto 1.85rem;
  max-width: 760px;
}

.hero-cta-group {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.95rem;
  margin-bottom: 2.25rem;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
  padding-top: 1.35rem;
  border-top: 1px solid var(--border-subtle);
}

.hero-stat {
  padding: 0.65rem 0.5rem;
}

.hero-stat__val {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--accent-cyan);
  font-family: var(--font-mono);
  line-height: 1.2;
}

.hero-stat__label {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* ==========================================================================
   GEO Quick Answer Box (AI Engine Optimization)
   ========================================================================== */

.geo-summary-box {
  margin-top: 2rem;
  padding: 1.35rem 1.5rem;
  border-radius: var(--radius-lg);
  background: rgba(11, 20, 42, 0.78);
  border: 1px solid rgba(45, 212, 191, 0.28);
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1.1rem;
  align-items: start;
}

.geo-summary-tag {
  padding: 0.3rem 0.72rem;
  border-radius: 8px;
  background: rgba(45, 212, 191, 0.16);
  color: var(--accent-teal);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  white-space: nowrap;
}

.geo-summary-box p {
  font-size: 0.94rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ==========================================================================
   Bento Features & Global Nodes
   ========================================================================== */

.bento-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
}

.glass-card {
  position: relative;
  border-radius: var(--radius-lg);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  padding: 1.55rem;
  backdrop-filter: blur(12px);
  transition: transform 0.24s ease, border-color 0.24s ease, background 0.24s ease;
}

.glass-card:hover {
  transform: translateY(-4px);
  border-color: rgba(56, 189, 248, 0.42);
  background: var(--bg-card-hover);
}

.card-icon {
  width: 46px;
  height: 46px;
  border-radius: 13px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 229, 255, 0.12);
  border: 1px solid rgba(0, 229, 255, 0.26);
  color: var(--accent-cyan);
  margin-bottom: 1rem;
}

.glass-card h3 {
  font-size: 1.12rem;
  font-weight: 700;
  margin-bottom: 0.55rem;
}

.glass-card p {
  font-size: 0.93rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* Nodes Grid */
.nodes-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
}

.node-card {
  padding: 1.15rem 1.2rem;
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  transition: border-color 0.22s ease, transform 0.22s ease;
}

.node-card:hover {
  border-color: var(--accent-teal);
  transform: translateY(-2px);
}

.node-card__top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}

.node-region {
  font-weight: 700;
  font-size: 1rem;
}

.node-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.18rem 0.5rem;
  border-radius: 6px;
  background: rgba(0, 229, 255, 0.12);
  color: var(--accent-cyan);
  white-space: nowrap;
  flex-shrink: 0;
}

.node-detail {
  font-size: 0.84rem;
  color: var(--text-muted);
}

/* ==========================================================================
   Pricing Section — STRICTLY ALL PLANS IN A SINGLE ROW (同排展示)
   ========================================================================== */

.pricing-billing-wrap {
  position: relative;
}

.billing-radio {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.billing-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem;
  border-radius: 14px;
  background: rgba(12, 19, 38, 0.9);
  border: 1px solid var(--border-subtle);
  margin: 0 auto 2.2rem;
}

.billing-toggle-outer {
  text-align: center;
}

.billing-tab {
  padding: 0.52rem 1.15rem;
  border-radius: 10px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
}

#bill-monthly:checked ~ .billing-toggle-outer label[for="bill-monthly"],
#bill-yearly:checked ~ .billing-toggle-outer label[for="bill-yearly"] {
  background: var(--gradient-cta);
  color: #ffffff;
  box-shadow: 0 6px 20px -6px rgba(0, 229, 255, 0.45);
}

.plan-price.price-yearly-val {
  display: none;
}

#bill-yearly:checked ~ .pricing-scroll .plan-price.price-monthly-val {
  display: none;
}

#bill-yearly:checked ~ .pricing-scroll .plan-price.price-yearly-val {
  display: inline-flex;
  align-items: baseline;
  gap: 0.25rem;
}

.pricing-scroll {
  width: 100%;
  overflow-x: auto;
  padding: 18px 0 0.65rem;
  scrollbar-width: thin;
  scrollbar-color: rgba(0, 229, 255, 0.35) transparent;
}

/* Force all 4 pricing cards strictly on ONE horizontal row */
.pricing-row {
  display: grid;
  grid-template-columns: repeat(4, minmax(255px, 1fr));
  gap: 1.2rem;
  align-items: stretch;
  min-width: 100%;
}

.plan-card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 1.75rem 1.45rem;
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, rgba(14, 22, 46, 0.88) 0%, rgba(8, 13, 29, 0.94) 100%);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-card);
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}

.plan-card:hover {
  transform: translateY(-5px);
  border-color: rgba(0, 229, 255, 0.48);
}

.plan-card--featured {
  border-color: rgba(0, 229, 255, 0.6);
  background: linear-gradient(180deg, rgba(16, 33, 66, 0.94) 0%, rgba(9, 16, 36, 0.98) 100%);
  box-shadow: 0 20px 55px -16px rgba(0, 229, 255, 0.34);
}

.plan-ribbon {
  position: absolute;
  top: -12px;
  right: 18px;
  padding: 0.28rem 0.78rem;
  border-radius: 999px;
  background: var(--gradient-brand);
  color: #03101d;
  font-size: 0.74rem;
  font-weight: 800;
  letter-spacing: 0.03em;
}

.plan-tier {
  font-size: 0.82rem;
  font-family: var(--font-mono);
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.35rem;
}

.plan-name {
  font-size: 1.24rem;
  font-weight: 800;
  margin-bottom: 0.45rem;
}

.plan-tagline {
  font-size: 0.85rem;
  color: var(--text-muted);
  min-height: 2.8em;
  margin-bottom: 1.15rem;
}

.plan-price-box {
  padding: 0.95rem 0;
  margin-bottom: 1.15rem;
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.plan-price {
  display: inline-flex;
  align-items: baseline;
  gap: 0.22rem;
}

.plan-currency {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--accent-cyan);
}

.plan-amount {
  font-size: 2.2rem;
  font-weight: 900;
  font-family: var(--font-mono);
  line-height: 1;
  color: #ffffff;
}

.plan-unit {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.plan-quota {
  margin-top: 0.45rem;
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--accent-teal);
}

.plan-features {
  display: flex;
  flex-direction: column;
  gap: 0.62rem;
  margin-bottom: 1.65rem;
  flex-grow: 1;
}

.plan-features li {
  display: flex;
  align-items: flex-start;
  gap: 0.55rem;
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.plan-check {
  color: var(--accent-teal);
  font-weight: 800;
  flex-shrink: 0;
}

.plan-cta {
  margin-top: auto;
}

.pricing-footnote {
  margin-top: 1.4rem;
  padding: 1rem 1.35rem;
  border-radius: var(--radius-md);
  background: rgba(12, 19, 38, 0.72);
  border: 1px solid var(--border-subtle);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.88rem;
  color: var(--text-secondary);
}

.scroll-hint {
  display: none;
  text-align: center;
  font-size: 0.8rem;
  color: var(--accent-cyan);
  margin-bottom: 0.75rem;
}

/* ==========================================================================
   3-Step Onboarding & External Client Authority Links
   ========================================================================== */

.steps-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
  margin-bottom: 2.5rem;
}

.step-card {
  padding: 1.5rem;
  border-radius: var(--radius-lg);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: var(--gradient-brand);
  color: #03101d;
  font-family: var(--font-mono);
  font-weight: 900;
  margin-bottom: 0.9rem;
}

.step-card h3 {
  font-size: 1.08rem;
  margin-bottom: 0.5rem;
}

.step-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.ext-links-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
}

.ext-link-card {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  padding: 1.15rem;
  border-radius: var(--radius-md);
  background: rgba(11, 18, 36, 0.78);
  border: 1px solid var(--border-subtle);
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.ext-link-card:hover {
  transform: translateY(-3px);
  border-color: var(--accent-cyan);
}

.ext-link-card__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-weight: 700;
  font-size: 0.96rem;
}

.ext-link-card__arrow {
  color: var(--accent-cyan);
  font-size: 0.86rem;
}

.ext-link-card p {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.55;
}

.ext-link-card__domain {
  margin-top: auto;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--accent-teal);
}

/* ==========================================================================
   Knowledge Hub & Articles Grid
   ========================================================================== */

.articles-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
}

.article-card {
  display: flex;
  flex-direction: column;
  padding: 1.55rem;
  border-radius: var(--radius-lg);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  transition: transform 0.24s ease, border-color 0.24s ease, background 0.24s ease;
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: rgba(0, 229, 255, 0.48);
  background: var(--bg-card-hover);
}

.article-card__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.75rem;
}

.tag-pill {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.22rem 0.65rem;
  border-radius: 999px;
  background: rgba(59, 130, 246, 0.16);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: #93c5fd;
}

.tag-pill--teal {
  background: rgba(45, 212, 191, 0.14);
  border-color: rgba(45, 212, 191, 0.32);
  color: #5eead4;
}

.article-card h3 {
  font-size: 1.14rem;
  font-weight: 700;
  line-height: 1.42;
  margin-bottom: 0.65rem;
}

.article-card p {
  font-size: 0.91rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 1.1rem;
  flex-grow: 1;
}

.article-card__foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--accent-cyan);
  padding-top: 0.85rem;
  border-top: 1px solid var(--border-subtle);
}

/* ==========================================================================
   User Reviews (Testimonials)
   ========================================================================== */

.reviews-summary {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 2.2rem;
  padding: 1.1rem 1.5rem;
  border-radius: var(--radius-md);
  background: rgba(12, 20, 42, 0.82);
  border: 1px solid rgba(245, 158, 11, 0.28);
}

.reviews-score {
  font-size: 1.85rem;
  font-weight: 900;
  font-family: var(--font-mono);
  color: #fbbf24;
}

.reviews-stars {
  color: #fbbf24;
  letter-spacing: 2px;
  font-size: 1.05rem;
}

.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
}

.review-card {
  display: flex;
  flex-direction: column;
  padding: 1.5rem;
  border-radius: var(--radius-lg);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
}

.review-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 0.9rem;
}

.reviewer {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.reviewer-avatar {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: var(--gradient-brand);
  color: #04101f;
  font-weight: 800;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.reviewer-name {
  font-weight: 700;
  font-size: 0.95rem;
}

.reviewer-role {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.review-plan {
  font-size: 0.74rem;
  font-family: var(--font-mono);
  padding: 0.2rem 0.55rem;
  border-radius: 6px;
  background: rgba(0, 229, 255, 0.1);
  color: var(--accent-cyan);
  white-space: nowrap;
}

.review-body {
  font-size: 0.91rem;
  color: var(--text-secondary);
  line-height: 1.72;
  margin-bottom: 1rem;
  flex-grow: 1;
}

.review-foot {
  font-size: 0.78rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* ==========================================================================
   FAQ Accordion (Pure Native HTML <details>)
   ========================================================================== */

.faq-list {
  max-width: 920px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.faq-item {
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-item[open] {
  border-color: rgba(0, 229, 255, 0.45);
  background: rgba(15, 25, 50, 0.88);
}

.faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 1.2rem 1.4rem;
  font-weight: 700;
  font-size: 1.02rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  user-select: none;
}

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

.faq-icon {
  width: 28px;
  height: 28px;
  border-radius: 8px;
  background: rgba(0, 229, 255, 0.12);
  color: var(--accent-cyan);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 1.15rem;
  flex-shrink: 0;
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  padding: 0 1.4rem 1.25rem;
  color: var(--text-secondary);
  font-size: 0.94rem;
  line-height: 1.78;
}

.faq-answer a {
  color: var(--accent-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ==========================================================================
   Bottom CTA Banner & Footer
   ========================================================================== */

.cta-banner {
  padding: 2.75rem 2rem;
  border-radius: var(--radius-xl);
  background: linear-gradient(135deg, rgba(0, 229, 255, 0.14) 0%, rgba(59, 130, 246, 0.16) 50%, rgba(139, 92, 246, 0.2) 100%);
  border: 1px solid rgba(0, 229, 255, 0.36);
  text-align: center;
  box-shadow: 0 24px 60px -24px rgba(0, 229, 255, 0.35);
}

.cta-banner h2 {
  font-size: clamp(1.5rem, 3vw, 2.2rem);
  font-weight: 800;
  margin-bottom: 0.8rem;
}

.cta-banner p {
  color: var(--text-secondary);
  max-width: 660px;
  margin: 0 auto 1.6rem;
}

.site-footer {
  border-top: 1px solid var(--border-subtle);
  background: rgba(4, 7, 17, 0.9);
  padding: 3.5rem 0 2rem;
  margin-top: 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1.2fr 1fr;
  gap: 2rem;
  margin-bottom: 2.5rem;
}

.footer-col h4 {
  font-size: 0.96rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.footer-col a {
  font-size: 0.87rem;
  color: var(--text-muted);
  transition: color 0.18s ease;
}

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

.footer-brand-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-top: 0.9rem;
  line-height: 1.7;
}

.footer-bottom {
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* ==========================================================================
   Responsive Breakpoints
   ========================================================================== */

@media (max-width: 1120px) {
  .bento-grid,
  .reviews-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .nodes-grid,
  .ext-links-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .scroll-hint {
    display: block;
  }
}

@media (max-width: 920px) {
  .main-nav {
    display: none;
  }

  .mobile-nav {
    display: block;
  }
}

@media (max-width: 720px) {
  .section {
    padding: 3.25rem 0;
  }

  .hero {
    padding: 3rem 0 2.5rem;
  }

  .hero-stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .bento-grid,
  .steps-grid,
  .articles-grid,
  .reviews-grid,
  .nodes-grid,
  .ext-links-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .geo-summary-box {
    grid-template-columns: 1fr;
  }

  .header-actions .btn--sm {
    padding: 0.48rem 0.82rem;
    font-size: 0.82rem;
  }
}