/* ==========================================================================
   火星联盟机场 (HXLM.MOM) - Mars Orbital Relay Native Stylesheet
   Pure CSS3 | Zero JS Dependencies | GPU-Accelerated Dynamic Cosmos
   ========================================================================== */

:root {
  --bg-void: #080707;
  --bg-basalt: #12100f;
  --bg-surface: rgba(24, 20, 18, 0.78);
  --bg-surface-strong: rgba(31, 25, 22, 0.92);
  --bg-elevated: rgba(42, 34, 29, 0.72);

  --mars-orange: #f97316;
  --mars-terracotta: #ea580c;
  --mars-crimson: #c2410c;
  --solar-amber: #fb923c;
  --titanium-100: #f5f5f4;
  --titanium-200: #e7e5e4;
  --titanium-400: #a8a29e;
  --titanium-500: #78716c;

  --status-live: #22c55e;
  --status-glow: rgba(34, 197, 94, 0.35);

  --border-subtle: rgba(231, 229, 228, 0.1);
  --border-mars: rgba(249, 115, 22, 0.32);
  --border-mars-bright: rgba(251, 146, 60, 0.72);

  --shadow-card: 0 18px 42px -18px rgba(0, 0, 0, 0.78);
  --shadow-mars: 0 14px 36px -10px rgba(234, 88, 12, 0.38);

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 22px;
  --radius-pill: 999px;

  --font-sans: "PingFang SC", "HarmonyOS Sans SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "Cascadia Mono", "JetBrains Mono", "SFMono-Regular", Consolas, monospace;

  --header-h: 72px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 20px);
  background-color: var(--bg-void);
  color: var(--titanium-200);
  font-size: 16px;
  overflow-x: clip;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-sans);
  line-height: 1.68;
  background: transparent;
  color: var(--titanium-200);
  overflow-x: clip;
  position: relative;
}

main,
.site-footer {
  position: relative;
  z-index: 1;
}

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

a {
  color: var(--solar-amber);
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease, background-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

a:hover {
  color: #fed7aa;
}

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

/* ==========================================================================
   Dynamic Mars Orbital Cosmos Background (Pure CSS Animations)
   ========================================================================== */
.mars-cosmos {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
  background:
    radial-gradient(ellipse 90% 55% at 50% -10%, rgba(194, 65, 12, 0.28), transparent 68%),
    radial-gradient(circle at 85% 22%, rgba(249, 115, 22, 0.17), transparent 46%),
    radial-gradient(circle at 12% 76%, rgba(154, 52, 18, 0.2), transparent 50%),
    linear-gradient(180deg, #090808 0%, #0d0a09 48%, #070606 100%);
}

.cosmos-grid {
  position: absolute;
  inset: -64px;
  background-image:
    linear-gradient(to right, rgba(249, 115, 22, 0.065) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(249, 115, 22, 0.065) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 85% 75% at 50% 30%, #000 35%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 85% 75% at 50% 30%, #000 35%, transparent 100%);
  animation: grid-drift 28s linear infinite;
}

.cosmos-stars {
  position: absolute;
  inset: -200px;
  background-image:
    radial-gradient(2px 2px at 14% 22%, rgba(255, 255, 255, 0.85) 35%, transparent 100%),
    radial-gradient(1.5px 1.5px at 28% 64%, rgba(254, 215, 170, 0.8) 35%, transparent 100%),
    radial-gradient(2.2px 2.2px at 42% 18%, rgba(255, 255, 255, 0.78) 35%, transparent 100%),
    radial-gradient(1.6px 1.6px at 59% 46%, rgba(251, 146, 60, 0.88) 35%, transparent 100%),
    radial-gradient(2px 2px at 74% 12%, rgba(255, 255, 255, 0.9) 35%, transparent 100%),
    radial-gradient(1.8px 1.8px at 88% 58%, rgba(254, 215, 170, 0.78) 35%, transparent 100%),
    radial-gradient(2px 2px at 22% 88%, rgba(255, 255, 255, 0.72) 35%, transparent 100%),
    radial-gradient(1.6px 1.6px at 66% 84%, rgba(251, 146, 60, 0.76) 35%, transparent 100%),
    radial-gradient(2px 2px at 93% 26%, rgba(255, 255, 255, 0.82) 35%, transparent 100%),
    radial-gradient(1.6px 1.6px at 7% 48%, rgba(254, 215, 170, 0.7) 35%, transparent 100%);
  background-size: 420px 420px;
  animation: starfield-pan 46s linear infinite, star-twinkle 6s ease-in-out infinite alternate;
}

.mars-nebula {
  position: absolute;
  border-radius: 50%;
  filter: blur(72px);
  will-change: transform, opacity;
}

.mars-nebula--primary {
  width: 620px;
  height: 620px;
  top: -170px;
  right: -110px;
  background: radial-gradient(circle, rgba(249, 115, 22, 0.32) 0%, rgba(194, 65, 12, 0.12) 55%, transparent 75%);
  animation: nebula-float-a 16s ease-in-out infinite alternate;
}

.mars-nebula--secondary {
  width: 540px;
  height: 540px;
  bottom: -140px;
  left: -130px;
  background: radial-gradient(circle, rgba(234, 88, 12, 0.25) 0%, rgba(124, 45, 18, 0.11) 55%, transparent 76%);
  animation: nebula-float-b 20s ease-in-out infinite alternate;
}

.orbital-ring {
  position: absolute;
  left: 50%;
  top: 24%;
  border-radius: 50%;
  border: 1px dashed rgba(249, 115, 22, 0.2);
  transform-origin: center;
  will-change: transform;
}

.orbital-ring--outer {
  width: 980px;
  height: 980px;
  margin-left: -490px;
  margin-top: -490px;
  animation: orbit-spin 90s linear infinite;
}

.orbital-ring--inner {
  width: 620px;
  height: 620px;
  margin-left: -310px;
  margin-top: -310px;
  border-style: solid;
  border-color: rgba(251, 146, 60, 0.08) transparent rgba(249, 115, 22, 0.16) transparent;
  animation: orbit-spin-reverse 62s linear infinite;
}

.orbital-ring::after {
  content: "";
  position: absolute;
  top: -4px;
  left: 50%;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--mars-orange);
  box-shadow: 0 0 14px 3px rgba(249, 115, 22, 0.7);
}

/* Mars Meteor Shower (Pure CSS Shooting Stars) */
.meteor {
  position: absolute;
  width: 190px;
  height: 2.5px;
  opacity: 0;
  border-radius: 999px;
  background: linear-gradient(
    90deg,
    #ffffff 0%,
    #fed7aa 18%,
    rgba(249, 115, 22, 0.8) 48%,
    rgba(234, 88, 12, 0.18) 80%,
    transparent 100%
  );
  transform-origin: left center;
  will-change: transform, opacity;
  animation: meteor-streak 5s linear infinite;
}

.meteor::before {
  content: "";
  position: absolute;
  left: -3px;
  top: 50%;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  transform: translateY(-50%);
  background: #ffffff;
  box-shadow:
    0 0 10px 3px #fed7aa,
    0 0 22px 6px rgba(249, 115, 22, 0.92);
}

.meteor--1 { top: 8%; left: 32%; width: 170px; animation-duration: 4.5s; animation-delay: -1.4s; }
.meteor--2 { top: 14%; left: 74%; width: 230px; animation-duration: 5.4s; animation-delay: -3.2s; }
.meteor--3 { top: 26%; left: 52%; width: 160px; animation-duration: 4.2s; animation-delay: 0.4s; }
.meteor--4 { top: 6%; left: 92%; width: 215px; animation-duration: 6.0s; animation-delay: -0.6s; }
.meteor--5 { top: 38%; left: 86%; width: 185px; animation-duration: 4.9s; animation-delay: 1.5s; }
.meteor--6 { top: 20%; left: 18%; width: 150px; animation-duration: 6.2s; animation-delay: -4.1s; }
.meteor--7 { top: 52%; left: 68%; width: 205px; animation-duration: 5.1s; animation-delay: 1.1s; }
.meteor--8 { top: 34%; left: 98%; width: 240px; animation-duration: 6.6s; animation-delay: -2.2s; }

@keyframes meteor-streak {
  0% {
    opacity: 0;
    transform: rotate(-35deg) translate3d(160px, 0, 0) scaleX(0.45);
  }
  8% {
    opacity: 1;
    transform: rotate(-35deg) translate3d(0, 0, 0) scaleX(1);
  }
  58% {
    opacity: 0.9;
    transform: rotate(-35deg) translate3d(-740px, 0, 0) scaleX(1);
  }
  75%, 100% {
    opacity: 0;
    transform: rotate(-35deg) translate3d(-980px, 0, 0) scaleX(0.75);
  }
}

@keyframes grid-drift {
  from {
    transform: translate3d(0, 0, 0);
  }
  to {
    transform: translate3d(64px, 64px, 0);
  }
}

@keyframes starfield-pan {
  from {
    transform: translate3d(0, 0, 0);
  }
  to {
    transform: translate3d(-120px, -180px, 0);
  }
}

@keyframes star-twinkle {
  0% {
    opacity: 0.52;
  }
  100% {
    opacity: 0.92;
  }
}

@keyframes nebula-float-a {
  0% {
    transform: translate3d(0, 0, 0) scale(1);
  }
  100% {
    transform: translate3d(-65px, 45px, 0) scale(1.12);
  }
}

@keyframes nebula-float-b {
  0% {
    transform: translate3d(0, 0, 0) scale(1);
  }
  100% {
    transform: translate3d(70px, -55px, 0) scale(1.14);
  }
}

@keyframes orbit-spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

@keyframes orbit-spin-reverse {
  from {
    transform: rotate(360deg);
  }
  to {
    transform: rotate(0deg);
  }
}

@keyframes pulse-beacon {
  0%, 100% {
    box-shadow: 0 0 0 0 var(--status-glow);
  }
  65% {
    box-shadow: 0 0 0 8px rgba(34, 197, 94, 0);
  }
}

@media (prefers-reduced-motion: reduce) {
  .cosmos-grid,
  .cosmos-stars,
  .mars-nebula,
  .orbital-ring,
  .meteor,
  .beacon-dot {
    animation: none !important;
  }
}

/* ==========================================================================
   Layout Containers & Utilities
   ========================================================================== */
.container {
  width: min(1200px, calc(100% - 2rem));
  margin-inline: auto;
}

.container-wide {
  width: min(1420px, calc(100% - 2rem));
  margin-inline: auto;
}

.section {
  padding: 4.5rem 0;
  position: relative;
}

.section-compact {
  padding: 3rem 0;
}

.section-head {
  max-width: 780px;
  margin-bottom: 2.25rem;
}

.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--solar-amber);
  margin-bottom: 0.55rem;
}

.section-title {
  margin: 0 0 0.75rem;
  font-size: clamp(1.65rem, 2.7vw, 2.35rem);
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: -0.02em;
  color: var(--titanium-100);
}

.section-desc {
  margin: 0;
  color: var(--titanium-400);
  font-size: 1rem;
}

/* ==========================================================================
   Header & Pure-CSS Mobile Navigation
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  height: var(--header-h);
  background: rgba(11, 9, 9, 0.84);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-subtle);
}

.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--titanium-100);
  flex-shrink: 0;
}

.brand-link:hover {
  color: var(--titanium-100);
}

.brand-logo {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1.5px solid var(--border-mars);
  box-shadow: 0 0 18px rgba(249, 115, 22, 0.28);
  flex-shrink: 0;
  background: #09090b;
}

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

.brand-name {
  font-size: 1.05rem;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--titanium-100);
}

.brand-domain {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--solar-amber);
  letter-spacing: 0.08em;
}

.nav-toggle {
  display: none;
}

.nav-toggle-btn {
  display: none;
  cursor: pointer;
  padding: 0.45rem 0.75rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface);
  color: var(--titanium-100);
  font-size: 0.88rem;
  font-weight: 600;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.3rem;
}

.site-nav a {
  padding: 0.45rem 0.78rem;
  border-radius: var(--radius-sm);
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--titanium-400);
  white-space: nowrap;
}

.site-nav a:hover {
  color: var(--titanium-100);
  background: rgba(249, 115, 22, 0.1);
}

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

/* ==========================================================================
   Buttons & CTA Controls
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  padding: 0.72rem 1.35rem;
  border-radius: var(--radius-sm);
  font-weight: 700;
  font-size: 0.94rem;
  line-height: 1.2;
  cursor: pointer;
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-sm {
  padding: 0.55rem 1.05rem;
  font-size: 0.86rem;
}

.btn-primary {
  background: linear-gradient(135deg, var(--mars-orange) 0%, var(--mars-terracotta) 100%);
  color: #fff;
  box-shadow: var(--shadow-mars);
}

.btn-primary:hover {
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 18px 40px -10px rgba(249, 115, 22, 0.55);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.04);
  border-color: var(--border-mars);
  color: var(--titanium-100);
}

.btn-secondary:hover {
  color: var(--titanium-100);
  background: rgba(249, 115, 22, 0.14);
  border-color: var(--border-mars-bright);
  transform: translateY(-1px);
}

.btn-block {
  width: 100%;
}

/* ==========================================================================
   Hero Section & Telemetry Card
   ========================================================================== */
.hero {
  padding: 4.25rem 0 3.5rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.18fr 0.82fr;
  gap: 2.5rem;
  align-items: center;
}

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.42rem 0.95rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border-mars);
  background: rgba(249, 115, 22, 0.1);
  color: #fed7aa;
  font-size: 0.84rem;
  font-weight: 600;
  margin-bottom: 1.35rem;
}

.beacon-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--status-live);
  animation: pulse-beacon 2.2s infinite;
}

.hero-title {
  margin: 0 0 1.15rem;
  font-size: clamp(2rem, 4.1vw, 3.2rem);
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: -0.025em;
  color: var(--titanium-100);
}

.hero-title .accent {
  background: linear-gradient(95deg, #fb923c 0%, #f97316 55%, #fdba74 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-lead {
  margin: 0 0 1.65rem;
  font-size: 1.06rem;
  color: var(--titanium-400);
  max-width: 62ch;
}

.hero-cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  margin-bottom: 1.8rem;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.38rem 0.78rem;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.035);
  border: 1px solid var(--border-subtle);
  font-size: 0.84rem;
  color: var(--titanium-200);
}

.telemetry-card {
  background: var(--bg-surface-strong);
  border: 1px solid var(--border-mars);
  border-radius: var(--radius-lg);
  padding: 1.6rem;
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
}

.telemetry-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--mars-crimson), var(--mars-orange), var(--solar-amber));
}

.telemetry-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.1rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--border-subtle);
}

.telemetry-title {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
  color: var(--titanium-100);
}

.telemetry-code {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--solar-amber);
  padding: 0.2rem 0.55rem;
  border-radius: 6px;
  background: rgba(249, 115, 22, 0.14);
}

.spec-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.78rem;
}

.spec-item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 0.75rem;
  font-size: 0.9rem;
  padding-bottom: 0.55rem;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.07);
}

.spec-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.spec-label {
  color: var(--titanium-400);
  flex-shrink: 0;
}

.spec-value {
  color: var(--titanium-100);
  font-weight: 600;
  text-align: right;
}

/* ==========================================================================
   Pricing Section - Strictly Single-Row (所有价格同排)
   ========================================================================== */
.pricing-group {
  margin-bottom: 2.75rem;
}

.pricing-group-bar {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.pricing-group-title {
  margin: 0;
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--titanium-100);
}

.pricing-group-hint {
  font-size: 0.84rem;
  color: var(--titanium-400);
  font-family: var(--font-mono);
}

/* 7 subscription tiers strictly in ONE horizontal row */
.pricing-row-7 {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 0.75rem;
  align-items: stretch;
}

/* 4 data pack tiers strictly in ONE horizontal row */
.pricing-row-4 {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
  align-items: stretch;
}

@media (max-width: 1219px) {
  .pricing-row-7 {
    grid-template-columns: none;
    grid-auto-flow: column;
    grid-auto-columns: minmax(192px, 1fr);
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    padding-bottom: 0.85rem;
    scrollbar-color: var(--mars-orange) rgba(255, 255, 255, 0.06);
    scrollbar-width: thin;
  }

  .pricing-row-7 > .price-card {
    scroll-snap-align: start;
  }
}

@media (max-width: 959px) {
  .pricing-row-4 {
    grid-template-columns: none;
    grid-auto-flow: column;
    grid-auto-columns: minmax(225px, 1fr);
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    padding-bottom: 0.85rem;
    scrollbar-color: var(--mars-orange) rgba(255, 255, 255, 0.06);
    scrollbar-width: thin;
  }

  .pricing-row-4 > .price-card {
    scroll-snap-align: start;
  }
}

.price-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.15rem 0.95rem;
  position: relative;
  transition: transform 0.22s ease, border-color 0.22s ease, box-shadow 0.22s ease;
  box-shadow: var(--shadow-card);
}

.price-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-mars-bright);
  box-shadow: 0 20px 38px -16px rgba(249, 115, 22, 0.32);
}

.price-card--featured {
  background: linear-gradient(180deg, rgba(249, 115, 22, 0.16) 0%, rgba(24, 20, 18, 0.92) 55%);
  border-color: var(--mars-orange);
}

.plan-tag {
  position: absolute;
  top: -11px;
  left: 50%;
  transform: translateX(-50%);
  padding: 0.16rem 0.65rem;
  border-radius: var(--radius-pill);
  background: linear-gradient(90deg, var(--mars-orange), var(--mars-terracotta));
  color: #fff;
  font-size: 0.72rem;
  font-weight: 800;
  white-space: nowrap;
}

.plan-head {
  margin-bottom: 0.8rem;
}

.plan-en {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--solar-amber);
}

.plan-name {
  margin: 0.15rem 0 0;
  font-size: 1.06rem;
  font-weight: 800;
  color: var(--titanium-100);
}

.plan-price-wrap {
  margin: 0.65rem 0 0.75rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-subtle);
}

.plan-price {
  display: flex;
  align-items: baseline;
  gap: 0.2rem;
  font-variant-numeric: tabular-nums;
}

.plan-currency {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--solar-amber);
}

.plan-amount {
  font-size: 1.85rem;
  font-weight: 900;
  line-height: 1;
  color: var(--titanium-100);
}

.plan-period {
  font-size: 0.82rem;
  color: var(--titanium-400);
}

.plan-subcycle {
  margin-top: 0.35rem;
  font-size: 0.74rem;
  color: var(--titanium-400);
  line-height: 1.38;
  min-height: 2.1em;
}

.plan-specs {
  list-style: none;
  margin: 0 0 1rem;
  padding: 0;
  display: grid;
  gap: 0.45rem;
  font-size: 0.82rem;
  color: var(--titanium-200);
}

.plan-specs li {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.plan-specs li::before {
  content: "▸";
  color: var(--mars-orange);
  font-size: 0.78rem;
  flex-shrink: 0;
}

.notice-banner {
  background: rgba(249, 115, 22, 0.08);
  border: 1px solid var(--border-mars);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  font-size: 0.92rem;
  color: var(--titanium-200);
}

.notice-banner strong {
  color: var(--solar-amber);
}

/* ==========================================================================
   Cards, Features, Nodes Table & GEO Summary
   ========================================================================== */
.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1.15rem;
}

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

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

@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }
  .grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .grid-3 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 680px) {
  .grid-4,
  .grid-3,
  .grid-2 {
    grid-template-columns: 1fr;
  }
}

.surface-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.4rem;
  box-shadow: var(--shadow-card);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.surface-card:hover {
  border-color: var(--border-mars);
  transform: translateY(-2px);
}

.card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: rgba(249, 115, 22, 0.14);
  border: 1px solid var(--border-mars);
  color: var(--solar-amber);
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 0.95rem;
  margin-bottom: 0.9rem;
}

.surface-card h3 {
  margin: 0 0 0.5rem;
  font-size: 1.08rem;
  font-weight: 700;
  color: var(--titanium-100);
}

.surface-card p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--titanium-400);
}

.table-wrap {
  overflow-x: auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface);
  box-shadow: var(--shadow-card);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 680px;
  text-align: left;
  font-size: 0.92rem;
}

.data-table th,
.data-table td {
  padding: 0.95rem 1.15rem;
  border-bottom: 1px solid var(--border-subtle);
}

.data-table thead th {
  background: rgba(249, 115, 22, 0.1);
  color: var(--titanium-100);
  font-weight: 700;
}

.data-table tbody tr:last-child td {
  border-bottom: none;
}

.data-table tbody tr:hover {
  background: rgba(255, 255, 255, 0.025);
}

.tag-live {
  display: inline-block;
  padding: 0.16rem 0.55rem;
  border-radius: var(--radius-pill);
  background: rgba(34, 197, 94, 0.15);
  color: #86efac;
  font-size: 0.76rem;
  font-weight: 600;
}

/* ==========================================================================
   Articles Knowledge Hub Cards
   ========================================================================== */
.article-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.4rem;
  box-shadow: var(--shadow-card);
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.article-card:hover {
  transform: translateY(-3px);
  border-color: var(--border-mars-bright);
}

.article-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 0.75rem;
}

.kw-chip {
  font-size: 0.74rem;
  padding: 0.18rem 0.56rem;
  border-radius: var(--radius-pill);
  background: rgba(249, 115, 22, 0.12);
  border: 1px solid rgba(249, 115, 22, 0.24);
  color: #fdba74;
}

.article-card h3 {
  margin: 0 0 0.6rem;
  font-size: 1.06rem;
  line-height: 1.42;
}

.article-card h3 a {
  color: var(--titanium-100);
}

.article-card h3 a:hover {
  color: var(--solar-amber);
}

.article-card p {
  margin: 0 0 1.1rem;
  font-size: 0.9rem;
  color: var(--titanium-400);
}

.article-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 0.8rem;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.83rem;
  color: var(--titanium-500);
}

.article-readmore {
  font-weight: 700;
  color: var(--solar-amber);
}

/* ==========================================================================
   User Reviews Section (用户评价)
   ========================================================================== */
.review-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.4rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 1rem;
}

.review-stars {
  color: #fbbf24;
  font-size: 0.92rem;
  letter-spacing: 0.08em;
}

.review-quote {
  margin: 0;
  font-size: 0.94rem;
  color: var(--titanium-200);
}

.review-author {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.82rem;
  color: var(--titanium-400);
}

.review-plan {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--solar-amber);
}

/* ==========================================================================
   FAQ Pure-CSS Accordion (<details> / <summary>)
   ========================================================================== */
.faq-list {
  display: grid;
  gap: 0.85rem;
}

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

.faq-item[open] {
  border-color: var(--border-mars);
  background: var(--bg-surface-strong);
}

.faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 1.15rem 1.35rem;
  font-weight: 700;
  font-size: 1rem;
  color: var(--titanium-100);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

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

.faq-item summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1.25rem;
  color: var(--mars-orange);
  transition: transform 0.2s ease;
  flex-shrink: 0;
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-answer {
  padding: 0 1.35rem 1.2rem;
  color: var(--titanium-400);
  font-size: 0.94rem;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 0.95rem;
}

/* ==========================================================================
   External Authority Links & Footer
   ========================================================================== */
.ext-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.9rem;
}

@media (max-width: 900px) {
  .ext-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 520px) {
  .ext-grid {
    grid-template-columns: 1fr;
  }
}

.ext-link-card {
  display: flex;
  flex-direction: column;
  gap: 0.28rem;
  padding: 1rem 1.1rem;
  border-radius: var(--radius-sm);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  color: var(--titanium-100);
}

.ext-link-card:hover {
  border-color: var(--border-mars-bright);
  background: var(--bg-surface-strong);
  transform: translateY(-2px);
}

.ext-link-card strong {
  font-size: 0.95rem;
  color: var(--titanium-100);
}

.ext-link-card span {
  font-size: 0.8rem;
  color: var(--titanium-400);
}

.cta-panel {
  background: linear-gradient(135deg, rgba(234, 88, 12, 0.24) 0%, rgba(24, 20, 18, 0.94) 62%);
  border: 1px solid var(--border-mars-bright);
  border-radius: var(--radius-lg);
  padding: 2.6rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1.5rem;
  box-shadow: var(--shadow-mars);
}

.cta-panel h2 {
  margin: 0 0 0.5rem;
  font-size: clamp(1.45rem, 2.6vw, 2rem);
  color: var(--titanium-100);
}

.cta-panel p {
  margin: 0;
  color: var(--titanium-200);
  max-width: 58ch;
}

.site-footer {
  border-top: 1px solid var(--border-subtle);
  background: rgba(8, 7, 7, 0.9);
  padding: 3rem 0 2.25rem;
  margin-top: 2rem;
}

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

@media (max-width: 900px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 560px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

.footer-col h4 {
  margin: 0 0 0.85rem;
  font-size: 0.95rem;
  color: var(--titanium-100);
}

.footer-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.48rem;
  font-size: 0.88rem;
}

.footer-links a {
  color: var(--titanium-400);
}

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

.footer-bottom {
  padding-top: 1.35rem;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  font-size: 0.82rem;
  color: var(--titanium-500);
}

/* ==========================================================================
   Article Page Layout & Internal Navigation
   ========================================================================== */
.article-page-wrap {
  padding: 2.75rem 0 4rem;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.86rem;
  color: var(--titanium-400);
  margin-bottom: 1.5rem;
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 310px;
  gap: 2.25rem;
  align-items: start;
}

@media (max-width: 980px) {
  .article-layout {
    grid-template-columns: 1fr;
  }
}

.article-shell {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: clamp(1.4rem, 3vw, 2.5rem);
  box-shadow: var(--shadow-card);
}

.article-header {
  padding-bottom: 1.4rem;
  margin-bottom: 1.65rem;
  border-bottom: 1px solid var(--border-subtle);
}

.article-h1 {
  margin: 0.65rem 0 0.85rem;
  font-size: clamp(1.6rem, 3vw, 2.25rem);
  line-height: 1.3;
  color: var(--titanium-100);
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: 0.84rem;
  color: var(--titanium-400);
}

.article-body {
  font-size: 1.02rem;
  line-height: 1.85;
  color: var(--titanium-200);
}

.article-body h2 {
  margin: 2rem 0 0.8rem;
  font-size: 1.38rem;
  color: var(--titanium-100);
  padding-left: 0.75rem;
  border-left: 3px solid var(--mars-orange);
}

.article-body h3 {
  margin: 1.4rem 0 0.6rem;
  font-size: 1.12rem;
  color: #fed7aa;
}

.article-body p {
  margin: 0 0 1.15rem;
}

.article-body ul,
.article-body ol {
  margin: 0 0 1.25rem;
  padding-left: 1.35rem;
}

.article-body li {
  margin-bottom: 0.45rem;
}

.article-tldr {
  background: rgba(249, 115, 22, 0.1);
  border: 1px solid var(--border-mars);
  border-radius: var(--radius-md);
  padding: 1.1rem 1.25rem;
  margin-bottom: 1.6rem;
  font-size: 0.94rem;
}

.article-tldr strong {
  color: var(--solar-amber);
}

.article-sidebar {
  display: grid;
  gap: 1.25rem;
  position: sticky;
  top: calc(var(--header-h) + 20px);
}

.sidebar-box {
  background: var(--bg-surface-strong);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.3rem;
}

.sidebar-box h3 {
  margin: 0 0 0.85rem;
  font-size: 1rem;
  color: var(--titanium-100);
}

.sidebar-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.65rem;
  font-size: 0.88rem;
}

.sidebar-links a {
  color: var(--titanium-200);
}

.sidebar-links a:hover {
  color: var(--solar-amber);
}

.article-pager {
  margin-top: 2.2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-subtle);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

@media (max-width: 620px) {
  .article-pager {
    grid-template-columns: 1fr;
  }
}

.pager-link {
  display: block;
  padding: 1rem 1.1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  background: rgba(255, 255, 255, 0.02);
}

.pager-link:hover {
  border-color: var(--border-mars);
  background: rgba(249, 115, 22, 0.08);
}

.pager-dir {
  display: block;
  font-size: 0.76rem;
  color: var(--titanium-400);
  margin-bottom: 0.25rem;
}

.pager-title {
  display: block;
  font-weight: 700;
  color: var(--titanium-100);
  font-size: 0.92rem;
}

/* ==========================================================================
   Mobile Navigation Collapse (Pure CSS Checkbox Hack)
   ========================================================================== */
@media (max-width: 960px) {
  .nav-toggle-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
  }

  .site-nav {
    display: none;
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    padding: 0.85rem 1rem 1.15rem;
    background: rgba(13, 11, 10, 0.97);
    border-bottom: 1px solid var(--border-mars);
    box-shadow: 0 22px 44px rgba(0, 0, 0, 0.8);
  }

  .nav-toggle:checked ~ .site-nav {
    display: flex;
  }

  .site-nav a {
    padding: 0.68rem 0.85rem;
  }

  .header-actions .btn-secondary {
    display: none;
  }
}