/* ===== Reset & Base ===== */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  /* Icon palette — navy interior, red frame, amber folder */
  --navy: #2e2e5e;
  --navy-deep: #222250;
  --navy-light: #3a3a6e;
  --red: #d63031;
  --red-hover: #bf2a2a;
  --red-light: #fceaea;
  --amber: #f0b818;
  --amber-hover: #dba515;
  --amber-light: #fdf6e3;

  --color-bg: #ffffff;
  --color-bg-warm: #faf8f5;
  --color-text: #222240;
  --color-text-secondary: #5e5e78;
  --color-border: #e4e0dc;
  --color-card-bg: #ffffff;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 3px rgba(46, 46, 94, 0.07);
  --shadow-md: 0 4px 16px rgba(46, 46, 94, 0.10);
  --shadow-lg: 0 8px 32px rgba(46, 46, 94, 0.14);

  --font-base: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-base);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  text-decoration: underline;
}

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

/* ===== Layout ===== */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Header ===== */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--navy);
  border-bottom: 3px solid var(--red);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.05rem;
  color: #fff;
  text-decoration: none;
}

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

.nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav a {
  color: rgba(255, 255, 255, 0.72);
  font-size: 0.9rem;
  font-weight: 500;
  text-decoration: none;
  transition: color 0.2s;
}

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

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s;
  cursor: pointer;
  border: none;
}

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

.btn-primary {
  background: var(--red);
  color: #fff;
}

.btn-primary:hover {
  background: var(--red-hover);
  box-shadow: 0 4px 16px rgba(214, 48, 49, 0.3);
}

.btn-secondary {
  background: var(--color-bg);
  color: var(--navy);
  border: 1.5px solid var(--color-border);
}

.btn-secondary:hover {
  border-color: var(--navy-light);
  background: #f4f3f8;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  padding: 80px 0 64px;
  text-align: center;
  background: var(--navy);
  color: #fff;
  overflow: hidden;
}

/* Amber glow at bottom — echoes the folder base */
.hero::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 180px;
  background: radial-gradient(ellipse, rgba(240, 184, 24, 0.12) 0%, transparent 70%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  max-width: 700px;
  margin: 0 auto;
  z-index: 1;
}

.hero-icon {
  margin-bottom: 24px;
}

.hero-icon img {
  width: 80px;
  height: 80px;
  filter: drop-shadow(0 4px 20px rgba(0, 0, 0, 0.35));
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -0.03em;
  margin-bottom: 18px;
  color: #fff;
}

.hero h1 .highlight {
  color: var(--amber);
}

.hero-subtitle {
  font-size: 1.1rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.72);
  margin-bottom: 36px;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 52px;
}

.hero-actions .btn-primary {
  background: var(--red);
  color: #fff;
}

.hero-actions .btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  border: 1.5px solid rgba(255, 255, 255, 0.2);
}

.hero-actions .btn-secondary:hover {
  background: rgba(255, 255, 255, 0.14);
  border-color: rgba(255, 255, 255, 0.35);
}

/* Demo window — red frame like icon */
.demo-window {
  background: var(--color-card-bg);
  border: 3px solid var(--red);
  border-radius: var(--radius-md);
  box-shadow: 0 16px 48px rgba(0, 0, 0, 0.35);
  overflow: hidden;
  max-width: 500px;
  margin: 0 auto;
}

.demo-titlebar {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 10px 14px;
  background: var(--red);
}

.demo-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.35);
}

.demo-content {
  padding: 44px 28px;
  background: #fafafa;
}

.demo-instruction {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  font-size: 1rem;
  color: var(--color-text-secondary);
}

.demo-instruction kbd {
  display: inline-block;
  padding: 6px 16px;
  background: var(--navy);
  color: #fff;
  border-radius: 6px;
  font-family: var(--font-base);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  box-shadow: 0 2px 0 var(--navy-deep);
}

/* ===== Section shared ===== */
.section-title {
  font-size: 1.9rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 8px;
  letter-spacing: -0.02em;
  color: var(--navy);
}

.section-subtitle {
  text-align: center;
  color: var(--color-text-secondary);
  font-size: 1.02rem;
  margin-bottom: 48px;
}

/* ===== Features ===== */
.features {
  padding: 84px 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.feature-card {
  padding: 28px 26px;
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--red);
  border-radius: var(--radius-md);
  background: var(--color-card-bg);
  transition: box-shadow 0.2s, transform 0.2s;
}

.feature-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  background: var(--red-light);
  color: var(--red);
  margin-bottom: 14px;
}

.feature-card h3 {
  font-size: 1.05rem;
  font-weight: 650;
  margin-bottom: 6px;
  color: var(--navy);
}

.feature-card p {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  line-height: 1.6;
}

.feature-card kbd {
  display: inline-block;
  padding: 2px 7px;
  background: var(--navy);
  color: #fff;
  border-radius: 4px;
  font-family: var(--font-base);
  font-size: 0.78rem;
  font-weight: 600;
}

/* ===== How it works ===== */
.how-it-works {
  padding: 84px 0;
  background: var(--amber-light);
  border-top: 3px solid var(--amber);
}

.steps {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 20px;
}

.step {
  text-align: center;
  max-width: 230px;
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--amber);
  color: var(--navy);
  font-weight: 800;
  font-size: 1.15rem;
  margin-bottom: 14px;
  box-shadow: 0 3px 0 var(--amber-hover);
}

.step h3 {
  font-size: 1.02rem;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--navy);
}

.step p {
  color: var(--color-text-secondary);
  font-size: 0.88rem;
}

.step-arrow {
  display: flex;
  align-items: center;
  margin-top: 12px;
  color: var(--amber-hover);
}

/* ===== Installation ===== */
.installation {
  padding: 84px 0;
}

.install-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  max-width: 780px;
  margin: 0 auto;
}

.install-card {
  padding: 32px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-card-bg);
  position: relative;
}

.install-card-primary {
  border-color: var(--red);
  border-width: 2px;
}

.install-badge {
  position: absolute;
  top: -11px;
  left: 24px;
  padding: 3px 14px;
  background: var(--red);
  color: #fff;
  font-size: 0.72rem;
  font-weight: 700;
  border-radius: 20px;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.install-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--navy);
}

.install-card p {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  margin-bottom: 20px;
}

.code-block {
  background: var(--navy);
  color: #c8cce0;
  padding: 14px 18px;
  border-radius: var(--radius-sm);
  font-family: 'Cascadia Code', 'Fira Code', 'Consolas', monospace;
  font-size: 0.85rem;
  overflow-x: auto;
  border-left: 3px solid var(--amber);
}

/* ===== Requirements ===== */
.requirements {
  padding: 56px 0;
  background: var(--color-bg-warm);
}

.requirements-list {
  display: flex;
  justify-content: center;
  gap: 40px;
  flex-wrap: wrap;
}

.requirement {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--color-text-secondary);
  font-size: 0.95rem;
}

.requirement svg {
  color: var(--red);
  flex-shrink: 0;
}

/* ===== Open Source ===== */
.open-source {
  padding: 80px 0;
  background: var(--navy);
  color: #fff;
  position: relative;
  overflow: hidden;
}

/* Gradient top border — red to amber like the icon's color flow */
.open-source::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--red), var(--amber), var(--red));
}

.open-source-inner {
  text-align: center;
  max-width: 560px;
  margin: 0 auto;
  position: relative;
}

.open-source h2 {
  font-size: 1.9rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: #fff;
}

.open-source p {
  color: rgba(255, 255, 255, 0.68);
  font-size: 0.98rem;
  margin-bottom: 28px;
  line-height: 1.7;
}

.open-source .btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  border: 1.5px solid rgba(255, 255, 255, 0.2);
}

.open-source .btn-secondary:hover {
  background: rgba(255, 255, 255, 0.14);
  border-color: rgba(255, 255, 255, 0.35);
}

/* ===== Footer ===== */
.footer {
  padding: 24px 0;
  background: var(--navy-deep);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.8);
}

.footer-copy {
  font-size: 0.82rem;
  color: rgba(255, 255, 255, 0.4);
}

.footer-copy a {
  color: rgba(255, 255, 255, 0.55);
  text-decoration: underline;
}

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

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 2.1rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

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

  .steps {
    flex-direction: column;
    align-items: center;
  }

  .step-arrow {
    transform: rotate(90deg);
    margin-top: 0;
  }

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

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

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

  .requirements-list {
    flex-direction: column;
    align-items: center;
  }
}

@media (max-width: 480px) {
  .hero {
    padding: 48px 0 40px;
  }

  .hero h1 {
    font-size: 1.75rem;
  }

  .features,
  .how-it-works,
  .installation,
  .open-source {
    padding: 56px 0;
  }

  .nav {
    gap: 16px;
  }

  .nav a {
    font-size: 0.82rem;
  }

  .feature-card {
    border-left-width: 3px;
  }
}