/* ==========================================================================
   flashcard-hika — Landing Page Stylesheet
   Minimal, Ultra-Fast, Responsive, Accessible
   ========================================================================== */

:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #3b82f6;
  --primary-subtle: #eff6ff;
  --accent: #0ea5e9;
  --text-main: #0f172a;
  --text-muted: #475569;
  --text-light: #94a3b8;
  --bg-page: #f8fafc;
  --bg-card: #ffffff;
  --border: #e2e8f0;
  --border-focus: #93c5fd;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 32px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 12px 28px -6px rgba(37, 99, 235, 0.12), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
  --shadow-mockup: 0 25px 50px -12px rgba(15, 23, 42, 0.25);
  --max-w: 1160px;
}

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

html {
  scroll-behavior: smooth;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  color: var(--text-main);
  background-color: var(--bg-page);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

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

a:hover {
  color: var(--primary-dark);
}

.container {
  width: 100%;
  max-width: var(--max-w);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* ==========================================================================
   Navigation Bar
   ========================================================================== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: all 0.2s ease;
}

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

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text-main);
  text-decoration: none;
}

.brand-logo {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  box-shadow: var(--shadow-sm);
}

.brand-name {
  background: linear-gradient(135deg, #1e40af 0%, #2563eb 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-muted);
  transition: color 0.2s ease;
}

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

.nav-btn {
  padding: 8px 18px;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
}

/* Mobile Nav Toggle */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--text-main);
}

/* ==========================================================================
   Buttons & CTAs
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  font-weight: 600;
  font-size: 1rem;
  padding: 14px 26px;
  border-radius: var(--radius-md);
  transition: all 0.2s ease;
  cursor: pointer;
  text-align: center;
  border: 1px solid transparent;
  line-height: 1.2;
}

.btn-primary {
  background-color: var(--primary);
  color: #ffffff;
  box-shadow: 0 4px 14px 0 rgba(37, 99, 235, 0.35);
}

.btn-primary:hover {
  background-color: var(--primary-dark);
  color: #ffffff;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px 0 rgba(37, 99, 235, 0.45);
}

.btn-secondary {
  background-color: #ffffff;
  color: var(--text-main);
  border-color: var(--border);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background-color: var(--primary-subtle);
  border-color: var(--border-focus);
  color: var(--primary);
  transform: translateY(-2px);
}

.btn-large {
  padding: 18px 36px;
  font-size: 1.1rem;
  border-radius: var(--radius-md);
}

.btn-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero {
  position: relative;
  padding: 64px 0 80px;
  background: linear-gradient(180deg, #eff6ff 0%, #f8fafc 100%);
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  align-items: center;
  gap: 48px;
}

.hero-content {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.release-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background-color: #ffffff;
  border: 1px solid #bfdbfe;
  border-radius: 9999px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary-dark);
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
}

.badge-dot {
  width: 8px;
  height: 8px;
  background-color: #10b981;
  border-radius: 50%;
}

.headline {
  font-size: 3.25rem;
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  color: var(--text-main);
  margin-bottom: 20px;
}

.headline .highlight {
  background: linear-gradient(135deg, #1e40af 0%, #2563eb 50%, #0ea5e9 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.subheadline {
  font-size: 1.18rem;
  line-height: 1.6;
  color: var(--text-muted);
  margin-bottom: 36px;
  max-width: 540px;
}

.cta-group {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 32px;
}

.trust-badges {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 20px;
  padding-top: 12px;
  border-top: 1px solid #e2e8f0;
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-muted);
}

.trust-check {
  color: #10b981;
  width: 16px;
  height: 16px;
}

/* ==========================================================================
   Hero App Mockup (Pure CSS / Lightweight SVG)
   ========================================================================== */
.mockup-wrapper {
  position: relative;
  display: flex;
  justify-content: center;
  perspective: 1000px;
}

.mockup-glow {
  position: absolute;
  width: 280px;
  height: 280px;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.28) 0%, rgba(37, 99, 235, 0) 70%);
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 0;
  filter: blur(24px);
}

.phone-frame {
  position: relative;
  z-index: 1;
  width: 320px;
  height: 620px;
  background: #0f172a;
  border-radius: 46px;
  padding: 12px;
  box-shadow: var(--shadow-mockup);
  border: 4px solid #334155;
  display: flex;
  flex-direction: column;
}

.phone-notch {
  position: absolute;
  top: 18px;
  left: 50%;
  transform: translateX(-50%);
  width: 96px;
  height: 20px;
  background-color: #0f172a;
  border-radius: 12px;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.notch-camera {
  width: 10px;
  height: 10px;
  background: #1e293b;
  border-radius: 50%;
  border: 1.5px solid #0f172a;
}

.phone-screen {
  width: 100%;
  height: 100%;
  background: #f1f5f9;
  border-radius: 36px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.app-header {
  background: #ffffff;
  padding: 38px 16px 12px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border);
}

.app-title-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
}

.app-mini-icon {
  width: 22px;
  height: 22px;
  border-radius: 6px;
}

.app-title {
  font-size: 0.88rem;
  font-weight: 800;
  color: var(--primary);
}

.app-mode-badge {
  font-size: 0.72rem;
  font-weight: 700;
  color: #1e40af;
  background: #dbeafe;
  padding: 3px 8px;
  border-radius: 6px;
}

.app-body {
  flex: 1;
  padding: 14px 12px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.app-nav-tabs {
  display: flex;
  background: #e2e8f0;
  padding: 3px;
  border-radius: 10px;
  width: 100%;
  gap: 4px;
}

.app-tab {
  flex: 1;
  text-align: center;
  padding: 6px 0;
  font-size: 0.76rem;
  font-weight: 700;
  color: var(--text-muted);
  border-radius: 8px;
}

.app-tab.active {
  background: #ffffff;
  color: var(--primary);
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.flashcard-box {
  width: 100%;
  background: #ffffff;
  border-radius: 20px;
  padding: 22px 14px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  box-shadow: 0 10px 25px -5px rgba(37, 99, 235, 0.15);
  border: 2px solid #bfdbfe;
  position: relative;
  margin: 6px 0;
}

.card-kana-char {
  font-size: 4.75rem;
  font-weight: 900;
  color: var(--primary);
  line-height: 1;
  margin-bottom: 6px;
  font-family: "Hiragino Kaku Gothic Pro", "Meiryo", sans-serif;
}

.card-romaji {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  background: #f8fafc;
  padding: 3px 14px;
  border-radius: 9999px;
  border: 1px solid var(--border);
}

.audio-play-btn {
  margin-top: 12px;
  display: flex;
  align-items: center;
  gap: 6px;
  background: #eff6ff;
  border: 1px solid #bfdbfe;
  padding: 6px 14px;
  border-radius: 9999px;
  color: var(--primary);
  font-size: 0.75rem;
  font-weight: 700;
  cursor: pointer;
}

.app-controls {
  width: 100%;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 6px;
}

.app-ctrl-btn {
  background: #ffffff;
  border: 1px solid var(--border);
  padding: 8px 6px;
  border-radius: 10px;
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--text-main);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  white-space: nowrap;
  cursor: pointer;
  width: 100%;
}

.app-ctrl-btn.primary {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

.app-card-counter {
  font-size: 0.74rem;
  font-weight: 800;
  color: var(--text-muted);
  white-space: nowrap;
  padding: 0 4px;
  text-align: center;
}

/* ==========================================================================
   Section: Fitur (Features Grid)
   ========================================================================== */
.section {
  padding: 90px 0;
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 56px;
}

.section-tag {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--primary);
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.35rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text-main);
  margin-bottom: 16px;
}

.section-desc {
  font-size: 1.1rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 28px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  transition: all 0.25s ease;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-sm);
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-focus);
  box-shadow: var(--shadow-lg);
}

.feature-icon-box {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: var(--primary-subtle);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.feature-icon {
  width: 26px;
  height: 26px;
}

.feature-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 12px;
}

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

/* ==========================================================================
   Section: Dokumentasi & Cara Pakai
   ========================================================================== */
.docs-section {
  background: #ffffff;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 32px;
}

.step-card {
  position: relative;
  background: var(--bg-page);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
}

.step-num {
  position: absolute;
  top: -16px;
  left: 24px;
  width: 34px;
  height: 34px;
  background: var(--primary);
  color: #ffffff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.95rem;
  font-weight: 800;
  box-shadow: 0 4px 10px rgba(37, 99, 235, 0.3);
}

.step-title {
  font-size: 1.18rem;
  font-weight: 700;
  margin-top: 6px;
  margin-bottom: 12px;
  color: var(--text-main);
}

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

.step-tip {
  margin-top: 14px;
  padding: 10px 14px;
  background: #ffffff;
  border-left: 3px solid var(--primary);
  border-radius: 4px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ==========================================================================
   Section: Download
   ========================================================================== */
.download-section {
  background: linear-gradient(180deg, var(--bg-page) 0%, #eff6ff 100%);
}

.download-card {
  max-width: 720px;
  margin: 0 auto;
  background: #ffffff;
  border: 1px solid #bfdbfe;
  border-radius: var(--radius-xl);
  padding: 48px 40px;
  text-align: center;
  box-shadow: var(--shadow-lg);
}

.download-app-icon {
  width: 72px;
  height: 72px;
  margin: 0 auto 20px;
  border-radius: 18px;
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.2);
}

.download-app-name {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 8px;
}

.download-tagline {
  font-size: 1rem;
  color: var(--text-muted);
  margin-bottom: 28px;
}

.meta-info-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  background: var(--bg-page);
  padding: 18px;
  border-radius: var(--radius-md);
  margin-bottom: 32px;
  border: 1px solid var(--border);
}

.meta-item-label {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 700;
  color: var(--text-light);
  margin-bottom: 4px;
}

.meta-item-val {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
}

.download-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.download-note {
  font-size: 0.85rem;
  color: var(--text-light);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.footer {
  background: #0f172a;
  color: #94a3b8;
  padding: 60px 0 32px;
  margin-top: auto;
}

.footer-top {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: flex-start;
  gap: 36px;
  padding-bottom: 40px;
  border-bottom: 1px solid #1e293b;
}

.footer-brand-wrap {
  max-width: 340px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 12px;
}

.footer-brand-icon {
  width: 32px;
  height: 32px;
  border-radius: 8px;
}

.footer-desc {
  font-size: 0.9rem;
  line-height: 1.6;
  color: #94a3b8;
}

.footer-nav {
  display: flex;
  gap: 48px;
}

.footer-nav-col {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-nav-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #ffffff;
  margin-bottom: 4px;
}

.footer-link {
  font-size: 0.9rem;
  color: #94a3b8;
  transition: color 0.2s ease;
}

.footer-link:hover {
  color: #ffffff;
}

.footer-bottom {
  padding-top: 32px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  font-size: 0.85rem;
}

/* ==========================================================================
   Responsive Breakpoints
   ========================================================================== */
@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 48px;
  }

  .hero-content {
    align-items: center;
  }

  .subheadline {
    margin-left: auto;
    margin-right: auto;
  }

  .cta-group {
    justify-content: center;
  }

  .trust-badges {
    justify-content: center;
  }

  .headline {
    font-size: 2.6rem;
  }
}

@media (max-width: 640px) {
  .nav-links {
    display: none;
  }

  .menu-toggle {
    display: block;
  }

  .headline {
    font-size: 2.15rem;
  }

  .subheadline {
    font-size: 1.05rem;
  }

  .cta-group {
    flex-direction: column;
    width: 100%;
  }

  .cta-group .btn {
    width: 100%;
  }

  .meta-info-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .phone-frame {
    width: 290px;
    height: 580px;
  }

  .card-kana-char {
    font-size: 4rem;
  }

  .download-card {
    padding: 32px 20px;
  }
}