/* ==========================================================================
   一分机场 (yfjichang.my) - 1980 Circulated Aluminum Penny Design System
   Visual Theme: 铝制流通分币：1980 岁月磨损与滚花齿边 (Circulated Aluminum Penny & Scratched Relief)
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Noto+Sans+SC:wght@300;400;500;700;900&family=JetBrains+Mono:wght@400;600&display=swap');

:root {
  --bg-slate: #E2E8F0;
  --bg-slate-light: #F1F5F9;
  --bg-card: #FFFFFF;
  --bg-card-alt: #F8FAFC;
  --text-main: #0F172A;
  --text-muted: #475569;
  --text-light: #64748B;
  --aluminum-silver: #CBD5E1;
  --aluminum-shine: #E2E8F0;
  --aluminum-dark: #334155;
  --border-groove: #CBD5E1;
  --border-dark: #0F172A;
  --accent-blue: #2563EB;
  --accent-green: #10B981;
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.08);
  --shadow-md: 0 4px 12px -2px rgba(15, 23, 42, 0.12);
  --shadow-lg: 0 10px 25px -5px rgba(15, 23, 42, 0.15);
  --shadow-metallic: inset 0 1px 0 rgba(255, 255, 255, 0.9), 0 4px 12px rgba(15, 23, 42, 0.08);
  --font-sans: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-slate);
  color: var(--text-main);
  line-height: 1.6;
  background-image: 
    radial-gradient(circle at 15% 20%, rgba(255, 255, 255, 0.6) 0%, transparent 40%),
    radial-gradient(circle at 85% 80%, rgba(203, 213, 225, 0.4) 0%, transparent 40%),
    linear-gradient(to bottom, #E2E8F0 0%, #E2E8F0 100%);
  background-attachment: fixed;
  overflow-x: hidden;
}

a {
  color: var(--text-main);
  text-decoration: none;
  transition: all 0.2s ease;
}

a:hover {
  color: var(--text-muted);
}

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

/* Micro Metallic Texture Container */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* Header & Navigation */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(226, 232, 240, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-groove);
  box-shadow: 0 2px 10px rgba(15, 23, 42, 0.05);
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 800;
  font-size: 1.35rem;
  letter-spacing: -0.02em;
  color: var(--text-main);
}

.coin-icon-mini {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: linear-gradient(135deg, #F8FAFC 0%, #CBD5E1 50%, #94A3B8 100%);
  border: 1px solid #94A3B8;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  font-weight: 900;
  color: #0F172A;
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.9), 0 2px 4px rgba(0,0,0,0.15);
  position: relative;
}

.coin-icon-mini::after {
  content: '';
  position: absolute;
  inset: 2px;
  border-radius: 50%;
  border: 1px dashed rgba(15, 23, 42, 0.3); /* Micro reeded edge */
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.75rem;
  list-style: none;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-muted);
  padding: 0.4rem 0.6rem;
  border-radius: 4px;
}

.nav-link:hover, .nav-link.active {
  color: var(--text-main);
  background: rgba(255, 255, 255, 0.5);
}

.btn-metallic {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-size: 0.95rem;
  font-weight: 700;
  color: #FFFFFF;
  background: linear-gradient(180deg, #1E293B 0%, #0F172A 100%);
  border: 1px solid #0F172A;
  border-radius: 4px;
  box-shadow: var(--shadow-metallic), 0 4px 10px rgba(15, 23, 42, 0.2);
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
  position: relative;
  overflow: hidden;
}

.btn-metallic::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; height: 50%;
  background: linear-gradient(to bottom, rgba(255, 255, 255, 0.15), rgba(255, 255, 255, 0));
  pointer-events: none;
}

.btn-metallic:hover {
  transform: translateY(-2px);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.9), 0 6px 16px rgba(15, 23, 42, 0.25);
  background: linear-gradient(180deg, #334155 0%, #0F172A 100%);
  color: #FFFFFF;
}

.btn-metallic:active {
  transform: translateY(1px);
  box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.4);
}

.btn-metallic-lg {
  padding: 1rem 2.25rem;
  font-size: 1.1rem;
}

.btn-metallic-outline {
  background: #FFFFFF;
  color: #0F172A;
  border: 1px solid #CBD5E1;
  box-shadow: var(--shadow-metallic);
}

.btn-metallic-outline:hover {
  background: #F8FAFC;
  color: #0F172A;
  border-color: #94A3B8;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: 1px solid var(--border-groove);
  padding: 0.5rem;
  border-radius: 4px;
  cursor: pointer;
}

/* Hero Section */
.hero-section {
  padding: 4rem 0 5rem;
  position: relative;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.badge-aluminum {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.9rem;
  background: #FFFFFF;
  border: 1px solid var(--border-groove);
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-main);
  box-shadow: var(--shadow-sm);
  margin-bottom: 1.25rem;
}

.badge-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--accent-green);
  box-shadow: 0 0 8px var(--accent-green);
}

.hero-title {
  font-size: 2.8rem;
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.03em;
  color: var(--text-main);
  margin-bottom: 1.25rem;
}

.hero-title span {
  background: linear-gradient(135deg, #0F172A 0%, #334155 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  position: relative;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
  line-height: 1.7;
}

.hero-ctas {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 2.5rem;
}

.hero-features-strip {
  display: flex;
  gap: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-groove);
}

.strip-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-muted);
}

.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}

.coin-card-wrapper {
  background: #FFFFFF;
  border: 1px solid var(--border-groove);
  border-radius: 12px;
  padding: 1.5rem;
  box-shadow: var(--shadow-lg), inset 0 1px 0 rgba(255,255,255,0.9);
  position: relative;
  transition: transform 0.3s ease;
}

.coin-card-wrapper:hover {
  transform: translateY(-4px);
}

.coin-image-container {
  width: 100%;
  max-width: 440px;
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--border-groove);
  box-shadow: inset 0 2px 4px rgba(0,0,0,0.05);
}

/* Card Styling - 1px Silver Inset Groove */
.card-groove {
  background: var(--bg-card);
  border: 1px solid var(--border-groove);
  border-radius: 8px;
  padding: 2rem;
  box-shadow: var(--shadow-metallic);
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
}

.card-groove:hover {
  border-color: #94A3B8;
  transform: translateY(-3px);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 1), 0 12px 24px -4px rgba(15, 23, 42, 0.12);
}

/* Section Common */
.section {
  padding: 5rem 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 750px;
  margin: 0 auto 3.5rem;
}

.section-tag {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.7);
  padding: 0.25rem 0.75rem;
  border-radius: 4px;
  border: 1px solid var(--border-groove);
  margin-bottom: 0.75rem;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
}

/* Advantage Grid */
.advantages-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.advantage-icon {
  width: 52px;
  height: 52px;
  border-radius: 8px;
  background: linear-gradient(135deg, #F1F5F9 0%, #CBD5E1 100%);
  border: 1px solid #94A3B8;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1.25rem;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

.advantage-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
  color: var(--text-main);
}

.advantage-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* Pricing Section - Referencing User Screenshot */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
  align-items: border-box;
}

.pricing-card {
  background: #FFFFFF;
  border: 1px solid #CBD5E1;
  border-radius: 4px;
  padding: 2.5rem 1.75rem 2rem;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-sm);
  position: relative;
  transition: all 0.2s ease;
}

.pricing-card.popular {
  border: 2px solid #0F172A;
  box-shadow: 0 8px 24px rgba(15, 23, 42, 0.15);
  transform: translateY(-6px);
}

.popular-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: #0F172A;
  color: #FFFFFF;
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.25rem 1rem;
  border-radius: 20px;
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.pricing-sub {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.pricing-traffic {
  font-size: 2.2rem;
  font-weight: 900;
  color: #0F172A;
  line-height: 1.1;
  margin-bottom: 0.75rem;
}

.pricing-price-box {
  display: flex;
  align-items: baseline;
  gap: 0.3rem;
  margin-bottom: 0.5rem;
}

.pricing-amount {
  font-size: 2.8rem;
  font-weight: 900;
  color: #0F172A;
  line-height: 1;
}

.pricing-unit {
  font-size: 0.95rem;
  color: var(--text-muted);
  font-weight: 500;
}

.pricing-cycle-details {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-bottom: 1.75rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px dashed var(--border-groove);
}

.pricing-features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-bottom: 2rem;
  flex-grow: 1;
}

.pricing-features li {
  font-size: 0.92rem;
  color: var(--text-main);
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
}

.pricing-features li span.check {
  font-weight: 900;
  color: var(--text-main);
}

.pricing-cta-btn {
  width: 100%;
  padding: 0.9rem 1rem;
  font-weight: 700;
  font-size: 0.95rem;
  text-align: center;
  background: #0F172A;
  color: #FFFFFF;
  border: none;
  border-radius: 2px;
  cursor: pointer;
  transition: background 0.2s ease;
}

.pricing-cta-btn:hover {
  background: #334155;
  color: #FFFFFF;
}

/* Speedtest Live Simulator Card */
.speedtest-widget-card {
  background: #FFFFFF;
  border: 1px solid var(--border-groove);
  border-radius: 8px;
  padding: 2rem;
  box-shadow: var(--shadow-lg);
}

.speedtest-controls {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border-groove);
}

.node-selector {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.node-btn {
  background: var(--bg-slate-light);
  border: 1px solid var(--border-groove);
  padding: 0.4rem 0.85rem;
  border-radius: 4px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.node-btn.active, .node-btn:hover {
  background: var(--text-main);
  color: #FFFFFF;
  border-color: var(--text-main);
}

.speed-meters-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.25rem;
  margin-bottom: 1.5rem;
}

.meter-box {
  background: var(--bg-card-alt);
  border: 1px solid var(--border-groove);
  padding: 1.25rem;
  border-radius: 6px;
  text-align: center;
}

.meter-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 700;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.meter-val {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--text-main);
}

.meter-unit {
  font-size: 0.75rem;
  color: var(--text-light);
}

/* User Reviews Section */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
}

.review-card {
  background: #FFFFFF;
  border: 1px solid var(--border-groove);
  border-radius: 8px;
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
}

.review-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
}

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

.avatar-coin {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, #E2E8F0 0%, #CBD5E1 100%);
  border: 1px solid #94A3B8;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.9rem;
  color: #0F172A;
}

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

.reviewer-role {
  font-size: 0.8rem;
  color: var(--text-light);
}

.stars {
  color: #F59E0B;
  font-size: 0.9rem;
}

.review-text {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* FAQ Accordion Styling */
.faq-list {
  max-width: 850px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background: #FFFFFF;
  border: 1px solid var(--border-groove);
  border-radius: 6px;
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-question {
  width: 100%;
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: none;
  border: none;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
  text-align: left;
  cursor: pointer;
}

.faq-icon {
  font-size: 1.2rem;
  font-weight: 400;
  transition: transform 0.25s ease;
}

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

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
  padding: 0 1.5rem;
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
  background: #F8FAFC;
}

.faq-item.open .faq-answer {
  max-height: 500px;
  padding: 1rem 1.5rem 1.5rem;
  border-top: 1px solid var(--border-groove);
}

/* Article List Grid */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 1.75rem;
}

.article-card {
  background: #FFFFFF;
  border: 1px solid var(--border-groove);
  border-radius: 8px;
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.article-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.article-tag {
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--text-muted);
  background: var(--bg-slate-light);
  padding: 0.2rem 0.6rem;
  border-radius: 3px;
  display: inline-block;
  margin-bottom: 0.75rem;
}

.article-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.75rem;
  line-height: 1.4;
}

.article-excerpt {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
  line-height: 1.6;
}

.article-meta {
  font-size: 0.8rem;
  color: var(--text-light);
  display: flex;
  justify-content: space-between;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border-groove);
}

/* Content Page & Article Layout */
.content-layout {
  padding: 3.5rem 0 5rem;
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.88rem;
  color: var(--text-light);
  margin-bottom: 2rem;
}

.breadcrumb a {
  color: var(--text-muted);
}

.breadcrumb span.sep {
  color: var(--text-light);
}

.article-body {
  background: #FFFFFF;
  border: 1px solid var(--border-groove);
  border-radius: 8px;
  padding: 3rem 2.5rem;
  box-shadow: var(--shadow-metallic);
  max-width: 900px;
  margin: 0 auto;
}

.article-body h1 {
  font-size: 2.2rem;
  font-weight: 900;
  color: var(--text-main);
  line-height: 1.3;
  margin-bottom: 1rem;
}

.article-header-meta {
  display: flex;
  gap: 1.5rem;
  font-size: 0.88rem;
  color: var(--text-light);
  padding-bottom: 1.5rem;
  margin-bottom: 2rem;
  border-bottom: 1px solid var(--border-groove);
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--text-main);
}

.article-content h2 {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--text-main);
  margin: 2.2rem 0 1rem;
  padding-bottom: 0.4rem;
  border-bottom: 2px solid var(--bg-slate-light);
}

.article-content h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin: 1.8rem 0 0.8rem;
}

.article-content p {
  margin-bottom: 1.4rem;
}

.article-content ul, .article-content ol {
  margin-bottom: 1.4rem;
  padding-left: 1.5rem;
}

.article-content li {
  margin-bottom: 0.5rem;
}

.article-content blockquote {
  background: var(--bg-slate-light);
  border-left: 4px solid var(--text-main);
  padding: 1.25rem;
  margin: 1.5rem 0;
  font-style: italic;
  color: var(--text-muted);
}

/* Callout Box inside Articles */
.article-cta-box {
  background: linear-gradient(135deg, #F8FAFC 0%, #E2E8F0 100%);
  border: 1px solid var(--border-groove);
  border-radius: 8px;
  padding: 2rem;
  margin: 2.5rem 0;
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.article-cta-title {
  font-size: 1.35rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  color: var(--text-main);
}

.article-cta-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

/* Footer Section */
.site-footer {
  background: #0F172A;
  color: #94A3B8;
  padding: 4rem 0 2rem;
  border-top: 1px solid #1E293B;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand .brand-logo {
  color: #FFFFFF;
  margin-bottom: 1rem;
}

.footer-desc {
  font-size: 0.9rem;
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

.footer-title {
  font-size: 0.95rem;
  font-weight: 800;
  color: #FFFFFF;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1.2rem;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.footer-links a {
  color: #94A3B8;
  font-size: 0.9rem;
}

.footer-links a:hover {
  color: #FFFFFF;
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid #1E293B;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.85rem;
}

/* Responsive Rules */
@media (max-width: 992px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  .pricing-grid {
    grid-template-columns: 1fr;
    max-width: 500px;
    margin: 0 auto;
  }
  .pricing-card.popular {
    transform: none;
  }
  .speed-meters-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 2.1rem;
  }
  .nav-links {
    display: none;
  }
  .mobile-menu-btn {
    display: block;
  }
  .article-body {
    padding: 1.75rem 1.25rem;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
}