/* ============================================================
   MPC-BE Official Website - Main Stylesheet
   Style: Flat, Modern, Professional (Dark Premium)
   Domain: www.mpcbe.cn
   ============================================================ */

/* -------- CSS Variables -------- */
:root {
  /* Brand colors - derived from MPC-BE "Black Edition" logo */
  --bg-primary: #0d0f12;
  --bg-secondary: #14171c;
  --bg-tertiary: #1a1e25;
  --bg-card: #1c2128;
  --bg-elevated: #222831;

  --border-color: #2a2f38;
  --border-light: #353b47;

  --text-primary: #f5f7fa;
  --text-secondary: #c9d1d9;
  --text-muted: #9ca3af;
  --text-dim: #6b7280;

  /* Accent - "play button" energy */
  --accent: #FF6B35;
  --accent-hover: #ff8556;
  --accent-soft: rgba(255, 107, 53, 0.12);
  --accent-glow: rgba(255, 107, 53, 0.35);

  /* Secondary accent - trust/tech blue */
  --accent-2: #2EA9DF;
  --accent-2-soft: rgba(46, 169, 223, 0.12);

  --success: #3FB950;
  --warning: #D29922;
  --danger: #F85149;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Roboto,
               "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;

  /* Spacing scale */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2.5rem;
  --space-2xl: 4rem;
  --space-3xl: 6rem;

  /* Layout */
  --container-width: 1200px;
  --container-narrow: 860px;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.6);
  --shadow-glow: 0 0 24px var(--accent-glow);

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-base: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}
button { outline: none } 
/* -------- Reset & Base -------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-secondary);
  line-height: 1.7;
  font-size: 1rem;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  min-height: 100vh;
}

/* Background ambient glow */
body::before {
  content: "";
  position: fixed;
  top: -200px;
  left: 50%;
  transform: translateX(-50%);
  width: 1200px;
  height: 600px;
  background: radial-gradient(ellipse at center, var(--accent-soft) 0%, transparent 60%);
  pointer-events: none;
  z-index: 0;
}

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

a {
  color: var(--accent-2);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}

/* -------- Typography -------- */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2.25rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.75rem, 3.5vw, 2.5rem); }
h3 { font-size: clamp(1.35rem, 2.5vw, 1.75rem); }
h4 { font-size: 1.2rem; }

p {
  margin-bottom: 1rem;
}

p:last-child {
  margin-bottom: 0;
}

.lead {
  font-size: 1.15rem;
  color: var(--text-muted);
  line-height: 1.7;
}

code {
  font-family: var(--font-mono);
  background: var(--bg-tertiary);
  padding: 0.15em 0.4em;
  border-radius: var(--radius-sm);
  font-size: 0.9em;
  color: var(--accent);
}

.text-accent {
  color: var(--accent);
}

.text-gradient {
  background: linear-gradient(135deg, var(--accent) 0%, #FFB088 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* -------- Layout Helpers -------- */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--space-xl);
  position: relative;
  z-index: 1;
}

.container-narrow {
  max-width: var(--container-narrow);
}

.section {
  padding: var(--space-3xl) 0;
  position: relative;
}

.section-sm {
  padding: var(--space-2xl) 0;
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto var(--space-2xl);
}

.section-eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent);
  padding: 0.3rem 0.8rem;
  border: 1px solid var(--accent);
  border-radius: var(--radius-full);
  margin-bottom: var(--space-md);
  background: var(--accent-soft);
}

.section-title {
  margin-bottom: var(--space-md);
}

.section-subtitle {
  color: var(--text-muted);
  font-size: 1.1rem;
}

/* -------- Buttons -------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.8rem 1.6rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
  cursor: pointer;
  border: 1px solid transparent;
  white-space: nowrap;
  text-decoration: none;
  font-family: inherit;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 4px 14px var(--accent-glow);
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 8px 22px var(--accent-glow);
}

.btn-secondary {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: var(--border-color);
}

.btn-secondary:hover {
  background: var(--bg-elevated);
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-2px);
}

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

.btn-ghost:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: var(--accent);
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.1rem;
}

.btn-block {
  display: flex;
  width: 100%;
}

.btn .icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

/* -------- Header / Navigation -------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(13, 15, 18, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border-color);
  transition: all var(--transition-base);
}

.site-header.scrolled {
  background: rgba(13, 15, 18, 0.95);
  box-shadow: 0 2px 16px rgba(0, 0, 0, 0.4);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  padding: 0 var(--space-xl);
  max-width: var(--container-width);
  margin: 0 auto;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--text-primary);
}

.nav-brand:hover {
  color: var(--text-primary);
}

.nav-brand img {
  height: 32px;
  width: auto;
}

.nav-brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.nav-brand-text small {
  font-size: 0.7rem;
  color: var(--text-muted);
  font-weight: 500;
  letter-spacing: 0.05em;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  padding: 0.5rem 0.95rem;
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.nav-link:hover {
  color: var(--text-primary);
  background: var(--bg-tertiary);
}

.nav-link.active {
  color: var(--accent);
  background: var(--accent-soft);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-left: 0.5rem;
}

.nav-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  align-items: center;
  justify-content: center;
}

.nav-toggle:hover {
  border-color: var(--accent);
}

.nav-toggle .icon {
  width: 20px;
  height: 20px;
  color: var(--text-primary);
}

/* -------- Hero Section -------- */
.hero {
  position: relative;
  padding: 8rem 0 5rem;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: var(--space-2xl);
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.9rem;
  background: var(--accent-soft);
  border: 1px solid var(--accent);
  border-radius: var(--radius-full);
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: var(--space-lg);
}

.hero-title {
  margin-bottom: var(--space-lg);
  line-height: 1.1;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-muted);
  margin-bottom: var(--space-xl);
  max-width: 540px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xl);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--border-color);
}

.hero-meta-item {
  display: flex;
  flex-direction: column;
}

.hero-meta-num {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 0.25rem;
}

.hero-meta-label {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* Hero visual */
.hero-visual {
  position: relative;
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: var(--space-md);
  box-shadow: var(--shadow-lg);
}

.hero-player {
  border-radius: var(--radius-md);
  background: #000;
  /*aspect-ratio: 16 / 10;*/
  height: 330px;
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-player::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f0f1a 100%);
}

.hero-player-controls {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-md);
}

.hero-play-btn {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 40px var(--accent-glow);
  animation: pulse 2.5s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { transform: scale(1); box-shadow: 0 0 40px var(--accent-glow); }
  50% { transform: scale(1.05); box-shadow: 0 0 60px var(--accent-glow); }
}

.hero-play-btn svg {
  width: 32px;
  height: 32px;
  color: #fff;
  margin-left: 4px;
}

.hero-player-bar {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: linear-gradient(transparent, rgba(0, 0, 0, 0.8));
  padding: var(--space-md);
  z-index: 2;
}

.hero-player-progress {
  height: 4px;
  background: rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: 0.5rem;
}

.hero-player-progress-fill {
  height: 100%;
  width: 42%;
  background: var(--accent);
  border-radius: var(--radius-full);
}

.hero-player-info {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.7);
}

.hero-player-chips {
  position: absolute;
  top: var(--space-md);
  left: var(--space-md);
  display: flex;
  gap: 0.4rem;
  z-index: 2;
}

.hero-chip {
  padding: 0.25rem 0.6rem;
  background: rgba(0, 0, 0, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-sm);
  font-size: 0.7rem;
  color: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(4px);
}

.hero-chip.accent {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

/* -------- Card Grid -------- */
.card-grid {
  display: grid;
  gap: var(--space-lg);
}

.card-grid-2 { grid-template-columns: repeat(2, 1fr); }
.card-grid-3 { grid-template-columns: repeat(3, 1fr); }
.card-grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-xl);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

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

.card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: var(--accent-soft);
  color: var(--accent);
  margin-bottom: var(--space-md);
}

.card-icon svg {
  width: 26px;
  height: 26px;
}

.card-icon.alt {
  background: var(--accent-2-soft);
  color: var(--accent-2);
}

.card-title {
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.card-text {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* -------- Usage Scenarios -------- */
.scenarios {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-lg);
}

.scenario {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  display: flex;
  gap: var(--space-lg);
  transition: all var(--transition-base);
}

.scenario:hover {
  border-color: var(--accent);
  background: var(--bg-elevated);
}

.scenario-visual {
  flex-shrink: 0;
  width: 64px;
  height: 64px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--accent-soft), transparent);
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
}

.scenario-visual svg {
  width: 30px;
  height: 30px;
}

.scenario-content h3 {
  font-size: 1.15rem;
  margin-bottom: 0.4rem;
}

.scenario-content p {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
}

.scenario-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.scenario-tag {
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  color: var(--text-muted);
}

/* -------- Testimonials -------- */
.testimonials {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
}

.testimonial {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  position: relative;
}

.testimonial::before {
  content: "\201C";
  position: absolute;
  top: 1rem;
  right: 1.5rem;
  font-size: 4rem;
  font-family: Georgia, serif;
  color: var(--accent);
  opacity: 0.25;
  line-height: 1;
}

.testimonial-rating {
  display: flex;
  gap: 0.15rem;
  color: var(--accent);
}

.testimonial-rating svg {
  width: 16px;
  height: 16px;
}

.testimonial-text {
  color: var(--text-secondary);
  font-size: 0.98rem;
  line-height: 1.7;
  flex: 1;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding-top: var(--space-md);
  border-top: 1px solid var(--border-color);
}

.testimonial-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #fff;
  font-size: 1rem;
  flex-shrink: 0;
}

.testimonial-author-info {
  display: flex;
  flex-direction: column;
}

.testimonial-author-name {
  font-weight: 600;
  color: var(--text-primary);
  font-size: 0.95rem;
}

.testimonial-author-role {
  color: var(--text-muted);
  font-size: 0.8rem;
}

/* -------- Stats Band -------- */
.stats-band {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
  padding: var(--space-2xl) 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
  text-align: center;
}

.stat-num {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 800;
  background: linear-gradient(135deg, var(--accent) 0%, #FFB088 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
  margin-bottom: 0.5rem;
}

.stat-label {
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* -------- Page Hero (inner pages) -------- */
.page-hero {
  padding: 8rem 0 3rem;
  text-align: center;
  position: relative;
}

.page-hero h1 {
  margin-bottom: var(--space-md);
}

.page-hero .lead {
  max-width: 720px;
  margin: 0 auto;
}

.breadcrumb {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: var(--space-md);
}

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

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

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

/* -------- Feature List (detailed) -------- */
.feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2xl);
  align-items: center;
  margin-bottom: var(--space-3xl);
}

.feature-row:nth-child(even) .feature-content {
  order: 2;
}

.feature-content h3 {
  font-size: 1.6rem;
  margin-bottom: var(--space-md);
}

.feature-content p {
  color: var(--text-muted);
  margin-bottom: var(--space-md);
}

.feature-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.feature-list li {
  display: flex;
  gap: 0.75rem;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.feature-list li::before {
  content: "";
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--accent-soft);
  border: 1.5px solid var(--accent);
  margin-top: 0.25rem;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23FF6B35' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'/%3E%3C/svg%3E");
  background-size: 12px;
  background-repeat: no-repeat;
  background-position: center;
}

.feature-visual {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  min-height: 320px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

.feature-visual-content {
  text-align: center;
  position: relative;
  z-index: 2;
}

.feature-visual-content .icon-big {
  width: 96px;
  height: 96px;
  margin: 0 auto var(--space-md);
  color: var(--accent);
  opacity: 0.85;
}

.feature-visual-content h4 {
  font-size: 1.1rem;
  color: var(--text-primary);
}

.feature-visual-content p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 0.5rem;
}

/* -------- Download Page -------- */
.download-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: var(--space-xl);
  align-items: start;
}

.download-main {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-2xl);
}

.download-aside {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.version-card {
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  background: var(--bg-tertiary);
  margin-bottom: var(--space-lg);
}

.version-card:last-child {
  margin-bottom: 0;
}

.version-card.featured {
  border-color: var(--accent);
  background: linear-gradient(135deg, var(--accent-soft), transparent);
}

.version-card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-md);
}

.version-name {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.version-badge {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.25rem 0.6rem;
  border-radius: var(--radius-full);
  background: var(--accent);
  color: #fff;
}

.version-badge.recommended {
  background: var(--success);
}

.version-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: var(--space-md);
}

.version-meta-item {
  font-size: 0.85rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.version-meta-item svg {
  width: 14px;
  height: 14px;
}

.version-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.info-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
}

.info-card h4 {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.05rem;
  margin-bottom: var(--space-md);
  color: var(--text-primary);
}

.info-card h4 svg {
  width: 18px;
  height: 18px;
  color: var(--accent);
}

.info-card ul {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.info-card li {
  display: flex;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
  padding-bottom: 0.5rem;
  border-bottom: 1px dashed var(--border-color);
}

.info-card li:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.info-card li strong {
  color: var(--text-primary);
  min-width: 110px;
  display: inline-block;
}

/* Changelog */
.changelog {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-2xl);
  margin-top: var(--space-xl);
}

.changelog h2 {
  margin-bottom: var(--space-xl);
}

.changelog-item {
  margin-bottom: var(--space-xl);
  padding-bottom: var(--space-xl);
  border-bottom: 1px solid var(--border-color);
}

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

.changelog-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: var(--space-md);
}

.changelog-version {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--accent);
}

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

.changelog-section h5 {
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin: var(--space-md) 0 0.5rem;
}

.changelog-list {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.changelog-list li {
  display: flex;
  gap: 0.6rem;
  font-size: 0.92rem;
  color: var(--text-secondary);
  padding-left: 0;
}

.changelog-list li::before {
  content: "›";
  color: var(--accent);
  font-weight: 700;
  flex-shrink: 0;
}

/* -------- Guide Page -------- */
.guide-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: var(--space-2xl);
  padding: var(--space-md);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
}

.guide-nav a {
  padding: 0.4rem 0.9rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  color: var(--text-secondary);
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
}

.guide-nav a:hover {
  color: var(--accent);
  border-color: var(--accent);
}

.guide-section {
  margin-bottom: var(--space-2xl);
  scroll-margin-top: 80px;
}

.guide-section h2 {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--border-color);
}

.guide-section h2 .num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: var(--accent);
  color: #fff;
  font-size: 1rem;
  font-weight: 700;
}

.shortcut-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.shortcut-table th,
.shortcut-table td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.92rem;
}

.shortcut-table th {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  font-weight: 600;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

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

.shortcut-table tr:hover td {
  background: var(--bg-tertiary);
}

.kbd {
  display: inline-block;
  padding: 0.15rem 0.5rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border-light);
  border-bottom-width: 2px;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-primary);
  min-width: 28px;
  text-align: center;
}

/* FAQ */
.faq-item {
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-md);
  background: var(--bg-card);
  overflow: hidden;
}

.faq-question {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-lg);
  cursor: pointer;
  font-weight: 600;
  color: var(--text-primary);
  user-select: none;
}

.faq-question:hover {
  color: var(--accent);
}

.faq-question .toggle {
  width: 20px;
  height: 20px;
  color: var(--accent);
  flex-shrink: 0;
  transition: transform var(--transition-base);
}

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

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-base), padding var(--transition-base);
  padding: 0 var(--space-lg);
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

.faq-item.open .faq-answer {
  max-height: 500px;
  padding: 0 var(--space-lg) var(--space-lg);
}

/* -------- About Page -------- */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2xl);
  align-items: center;
  margin-bottom: var(--space-2xl);
}

.about-text h2 {
  margin-bottom: var(--space-md);
}

.about-text p {
  color: var(--text-muted);
  margin-bottom: var(--space-md);
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-md);
  margin-top: var(--space-lg);
}

.about-stat {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  text-align: center;
}

.about-stat-num {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--accent);
}

.about-stat-label {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.timeline {
  position: relative;
  padding-left: 2rem;
  margin-top: var(--space-2xl);
}

.timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border-color);
}

.timeline-item {
  position: relative;
  margin-bottom: var(--space-xl);
  padding-bottom: var(--space-xl);
}

.timeline-item:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
}

.timeline-dot {
  position: absolute;
  left: -2rem;
  top: 0.4rem;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--bg-primary);
  border: 3px solid var(--accent);
}

.timeline-date {
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 0.3rem;
}

.timeline-title {
  font-size: 1.1rem;
  color: var(--text-primary);
  margin-bottom: 0.3rem;
}

.timeline-text {
  color: var(--text-muted);
  font-size: 0.92rem;
}

/* Tech badges */
.tech-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: var(--space-md);
}

.tech-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.4rem 0.8rem;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  color: var(--text-secondary);
}

.tech-badge svg {
  width: 14px;
  height: 14px;
  color: var(--accent);
}

/* -------- CTA Band -------- */
.cta-band {
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-2xl);
  text-align: center;
  margin: var(--space-2xl) 0;
  position: relative;
  overflow: hidden;
}

.cta-band::before {
  content: "";
  position: absolute;
  top: -50%;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--accent-soft) 0%, transparent 60%);
  pointer-events: none;
}

.cta-band > * {
  position: relative;
  z-index: 1;
}

.cta-band h2 {
  margin-bottom: var(--space-md);
}

.cta-band p {
  color: var(--text-muted);
  max-width: 540px;
  margin: 0 auto var(--space-xl);
}

.cta-band-actions {
  display: flex;
  justify-content: center;
  gap: var(--space-md);
  flex-wrap: wrap;
}

/* -------- Footer -------- */
.site-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: var(--space-2xl) 0 var(--space-lg);
  margin-top: var(--space-3xl);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: var(--space-xl);
  margin-bottom: var(--space-xl);
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: var(--space-md);
  max-width: 320px;
}

.footer-col h5 {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-md);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-col a {
  color: var(--text-muted);
  font-size: 0.9rem;
}

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

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-lg);
  border-top: 1px solid var(--border-color);
  color: var(--text-dim);
  font-size: 0.85rem;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.footer-social {
  display: flex;
  gap: 0.5rem;
}

.footer-social a {
  width: 36px;
  height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  color: var(--text-muted);
}

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

.footer-social svg {
  width: 18px;
  height: 18px;
}

/* -------- Download Modal -------- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-base), visibility var(--transition-base);
  padding: var(--space-md);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
}

.modal {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  max-width: 600px;
  width: 100%;
  padding: var(--space-2xl);
  position: relative;
  transform: translateY(20px) scale(0.98);
  transition: transform var(--transition-base);
  box-shadow: var(--shadow-lg);
  max-height: 80vh;
  overflow-y: auto;
}

.modal-overlay.active .modal {
  transform: translateY(0) scale(1);
}

.modal-close {
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: var(--bg-tertiary);
  color: var(--text-muted);
  transition: all var(--transition-fast);
}

.modal-close:hover {
  background: var(--bg-elevated);
  color: var(--accent);
}

.modal-close svg {
  width: 18px;
  height: 18px;
}

.modal-header {
  text-align: center;
  margin-bottom: var(--space-xl);
}

.modal-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto var(--space-md);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
}

.modal-icon svg {
  width: 32px;
  height: 32px;
}

.modal-title {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.modal-subtitle {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.qr-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.qr-card {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  text-align: center;
  transition: all var(--transition-fast);
}

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

.qr-card img {
  width: 100%;
  max-width: 180px;
  margin: 0 auto var(--space-sm);
  border-radius: var(--radius-sm);
  background: #fff;
  padding: 8px;
}

.qr-card-title {
  font-weight: 600;
  color: var(--text-primary);
  font-size: 0.95rem;
  margin-bottom: 0.25rem;
}

.qr-card-desc {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.modal-cta {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.modal-footer {
  text-align: center;
  padding-top: var(--space-md);
  border-top: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.85rem;
}

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

/* -------- Toast / Notification -------- */
.toast {
  position: fixed;
  bottom: var(--space-xl);
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: var(--bg-elevated);
  border: 1px solid var(--accent);
  border-radius: var(--radius-md);
  padding: var(--space-md) var(--space-lg);
  color: var(--text-primary);
  font-size: 0.95rem;
  box-shadow: var(--shadow-lg);
  z-index: 1100;
  opacity: 0;
  transition: all var(--transition-base);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.toast.show {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

.toast svg {
  width: 20px;
  height: 20px;
  color: var(--success);
}

/* -------- Animations -------- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  animation: fadeInUp 0.6s ease-out backwards;
}

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* -------- Responsive -------- */
@media (max-width: 980px) {
  .hero-grid,
  .feature-row,
  .download-grid,
  .about-grid {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .feature-row:nth-child(even) .feature-content {
    order: 0;
  }

  .card-grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }

  .scenarios,
  .testimonials {
    grid-template-columns: 1fr;
  }

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

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-xl);
  }
}

@media (max-width: 720px) {
  html {
    font-size: 15px;
  }

  .nav-menu {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    flex-direction: column;
    align-items: stretch;
    padding: var(--space-md);
    gap: 0.25rem;
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-lg);
  }

  .nav-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-link {
    padding: 0.75rem 1rem;
    border-radius: var(--radius-sm);
  }

  .nav-toggle {
    display: inline-flex;
  }

  .nav-actions .btn {
    display: none;
  }

  .container {
    padding: 0 var(--space-md);
  }

  .section {
    padding: var(--space-2xl) 0;
  }

  .hero {
    padding: 6rem 0 3rem;
  }

  .hero-actions .btn {
    flex: 1;
  }

  .card-grid-2,
  .card-grid-3,
  .card-grid-4 {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }

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

  .modal {
    padding: var(--space-lg);
  }

  .scenario {
    flex-direction: column;
  }

  .stats-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
  }

  .version-actions {
    flex-direction: column;
  }

  .version-actions .btn {
    width: 100%;
  }
}

@media (max-width: 420px) {
  .hero-meta {
    gap: var(--space-md);
  }

  .hero-meta-num {
    font-size: 1.3rem;
  }

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

/* -------- Print -------- */
@media print {
  .site-header,
  .site-footer,
  .nav-actions,
  .modal-overlay,
  .cta-band {
    display: none;
  }

  body {
    background: #fff;
    color: #000;
  }
}

/* -------- Accessibility -------- */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.skip-link {
  position: absolute;
  top: -100px;
  left: var(--space-md);
  background: var(--accent);
  color: #fff;
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-sm);
  z-index: 2000;
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: var(--space-md);
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}