/* ==========================================================================
   DownloaderFree.com - Design System & Master Stylesheet
   Modern, Accessible, High-Utility Platform Architecture
   ========================================================================== */

:root {
  /* Brand Color Tokens */
  --color-primary: #2563EB;
  --color-primary-hover: #1D4ED8;
  --color-primary-active: #1E40AF;
  --color-primary-light: #EFF6FF;
  --color-primary-border: #BFDBFE;

  --color-surface-bg: #F8FAFC;
  --color-surface-card: #FFFFFF;
  --color-surface-card-hover: #F1F5F9;
  --color-surface-elevated: #FFFFFF;

  --color-text-main: #0F172A;
  --color-text-muted: #475569;
  --color-text-subtle: #64748B;
  --color-text-inverse: #FFFFFF;

  --color-border: #E2E8F0;
  --color-border-hover: #CBD5E1;
  --color-border-focus: #3B82F6;

  /* Semantic Feedback Tokens */
  --color-success: #059669;
  --color-success-bg: #ECFDF5;
  --color-success-border: #A7F3D0;

  --color-warning: #D97706;
  --color-warning-bg: #FFFBEB;
  --color-warning-border: #FDE68A;

  --color-danger: #DC2626;
  --color-danger-bg: #FEF2F2;
  --color-danger-border: #FECACA;

  --color-info: #0284C7;
  --color-info-bg: #F0F9FF;
  --color-info-border: #BAE6FD;

  /* Typography Scale */
  --font-display: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

  /* Radius & Shadows */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  --shadow-xs: 0 1px 2px 0 rgba(15, 23, 42, 0.05);
  --shadow-sm: 0 1px 3px 0 rgba(15, 23, 42, 0.08), 0 1px 2px -1px rgba(15, 23, 42, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(15, 23, 42, 0.07), 0 2px 4px -2px rgba(15, 23, 42, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(15, 23, 42, 0.08), 0 4px 6px -4px rgba(15, 23, 42, 0.04);
  --shadow-xl: 0 20px 25px -5px rgba(15, 23, 42, 0.1), 0 8px 10px -6px rgba(15, 23, 42, 0.04);
  --shadow-glow: 0 0 0 3px rgba(37, 99, 235, 0.2);

  /* Layout Constraints */
  --max-w-content: 1240px;
  --header-height: 72px;
}

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

html {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.5;
  color: var(--color-text-main);
  background-color: var(--color-surface-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

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

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

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.15s ease;
}

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

button, input, textarea, select {
  font: inherit;
  color: inherit;
}

/* Layout Utilities */
.container {
  width: 100%;
  max-width: var(--max-w-content);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

.container-narrow {
  max-width: 860px;
}

/* Header & Navigation */
.site-header {
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  gap: 0.75rem;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.03em;
  color: var(--color-text-main);
  text-decoration: none;
  flex-shrink: 0;
  white-space: nowrap;
}

.brand-icon {
  width: 32px;
  height: 32px;
  background: var(--color-primary);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  flex-shrink: 0;
  box-shadow: 0 2px 4px rgba(37, 99, 235, 0.25);
}

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

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  flex-wrap: nowrap;
}

.nav-desktop a,
.nav-link {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text-muted);
  padding: 0.45rem 0.65rem;
  border-radius: var(--radius-sm);
  transition: all 0.15s ease;
  white-space: nowrap;
  line-height: 1.2;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
}

.nav-desktop a:hover,
.nav-desktop a.active,
.nav-link:hover,
.nav-link.active {
  color: var(--color-primary);
  background: var(--color-primary-light);
  text-decoration: none;
}

.header-cta-group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-shrink: 0;
}

.btn-header-cta {
  font-size: 0.85rem;
  font-weight: 600;
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-md);
  background: var(--color-primary);
  color: white;
  border: none;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  white-space: nowrap;
  line-height: 1;
  transition: all 0.15s ease;
}

.btn-header-cta svg {
  flex-shrink: 0;
}

.btn-header-cta:hover {
  background: var(--color-primary-hover);
  color: white;
  transform: translateY(-1px);
}

.nav-toggle-btn {
  display: none;
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 0.45rem;
  cursor: pointer;
  color: var(--color-text-main);
  flex-shrink: 0;
}

/* Mobile Nav Drawer */
.mobile-nav-drawer {
  position: fixed;
  top: var(--header-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: white;
  border-bottom: 1px solid var(--color-border);
  padding: 1.5rem;
  overflow-y: auto;
  display: none;
  flex-direction: column;
  gap: 1rem;
  z-index: 99;
}

.mobile-nav-drawer.open {
  display: flex;
}

.mobile-nav-link {
  font-size: 1.05rem;
  font-weight: 600;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-md);
  color: var(--color-text-main);
  background: var(--color-surface-bg);
}

.mobile-nav-link:hover,
.mobile-nav-link.active {
  background: var(--color-primary-light);
  color: var(--color-primary);
}

/* Hero Section */
.hero-section {
  padding: 3.5rem 0 2rem;
  text-align: center;
  position: relative;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.85rem;
  background: var(--color-primary-light);
  border: 1px solid var(--color-primary-border);
  border-radius: var(--radius-full);
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 1.25rem;
}

.hero-title {
  font-family: var(--font-display);
  font-size: 2.75rem;
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.035em;
  color: var(--color-text-main);
  margin-bottom: 1rem;
  max-width: 820px;
  margin-left: auto;
  margin-right: auto;
}

.hero-subtitle {
  font-size: 1.15rem;
  line-height: 1.6;
  color: var(--color-text-muted);
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 2rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--font-body);
  font-size: 0.9375rem;
  font-weight: 600;
  line-height: 1.2;
  padding: 0.75rem 1.35rem;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.15s ease;
  border: 1px solid transparent;
  text-decoration: none;
}

.btn-primary {
  background: var(--color-primary);
  color: white;
  box-shadow: 0 1px 3px rgba(37, 99, 235, 0.2);
}

.btn-primary:hover {
  background: var(--color-primary-hover);
  color: white;
  box-shadow: 0 4px 10px rgba(37, 99, 235, 0.3);
  transform: translateY(-1px);
}

.btn-secondary {
  background: white;
  color: var(--color-text-main);
  border-color: var(--color-border);
  box-shadow: var(--shadow-xs);
}

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

.btn-sm {
  padding: 0.45rem 0.85rem;
  font-size: 0.8125rem;
  border-radius: var(--radius-sm);
}

.btn-lg {
  padding: 0.95rem 1.75rem;
  font-size: 1.05rem;
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
}

.btn-outline:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: var(--color-primary-light);
}

/* Cards & Grid */
.grid-tools {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
}

.tool-card {
  background: var(--color-surface-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  box-shadow: var(--shadow-xs);
}

.tool-card:hover {
  border-color: var(--color-primary-border);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.tool-card-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--color-primary-light);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.15rem;
  font-size: 1.25rem;
  flex-shrink: 0;
}

.tool-card-title {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-text-main);
  margin-bottom: 0.5rem;
  letter-spacing: -0.015em;
}

.tool-card-desc {
  font-size: 0.925rem;
  color: var(--color-text-muted);
  line-height: 1.55;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.tool-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid var(--color-border);
}

.tool-card-meta {
  font-size: 0.8125rem;
  color: var(--color-text-subtle);
  font-weight: 500;
}

.tool-card-action {
  font-weight: 600;
  font-size: 0.875rem;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  color: var(--color-primary);
}

.tool-card:hover .tool-card-action {
  color: var(--color-primary-hover);
  text-decoration: underline;
}

/* Category Grid */
.grid-categories {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.25rem;
}

.category-card {
  background: white;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.35rem;
  text-decoration: none;
  transition: all 0.15s ease;
  display: flex;
  flex-direction: column;
}

.category-card:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-sm);
  transform: translateY(-2px);
}

.category-card-head {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.5rem;
}

.category-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: var(--color-surface-bg);
  border: 1px solid var(--color-border);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
}

.category-title {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-text-main);
}

.category-desc {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  line-height: 1.45;
}

/* Section Containers */
.section {
  padding: 3.5rem 0;
}

.section-head {
  margin-bottom: 2rem;
}

.section-head-center {
  text-align: center;
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 2.5rem;
}

.section-tag {
  font-size: 0.8125rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-primary);
  margin-bottom: 0.5rem;
}

.section-title {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  color: var(--color-text-main);
  margin-bottom: 0.75rem;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

/* How It Works Steps */
.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  position: relative;
}

.step-card {
  background: white;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  position: relative;
}

.step-num {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 2rem;
  color: var(--color-primary-border);
  line-height: 1;
  margin-bottom: 1rem;
}

.step-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--color-text-main);
}

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

/* Callout & Alert Boxes */
.alert-box {
  border-radius: var(--radius-md);
  padding: 1.25rem;
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  margin: 1.5rem 0;
  font-size: 0.95rem;
  line-height: 1.55;
}

.alert-info {
  background: var(--color-info-bg);
  border: 1px solid var(--color-info-border);
  color: #0369A1;
}

.alert-warning {
  background: var(--color-warning-bg);
  border: 1px solid var(--color-warning-border);
  color: #B45309;
}

.alert-success {
  background: var(--color-success-bg);
  border: 1px solid var(--color-success-border);
  color: #047857;
}

.alert-danger {
  background: var(--color-danger-bg);
  border: 1px solid var(--color-danger-border);
  color: #B91C1C;
}

/* FAQ Accordion */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 820px;
  margin: 0 auto;
}

.faq-item {
  background: white;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.15s ease;
}

.faq-item:hover {
  border-color: var(--color-border-hover);
}

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

.faq-icon {
  font-size: 1.25rem;
  color: var(--color-text-subtle);
  transition: transform 0.2s ease;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
  color: var(--color-primary);
}

.faq-answer {
  padding: 0 1.5rem 1.25rem;
  color: var(--color-text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
  display: none;
}

.faq-item.active .faq-answer {
  display: block;
}

/* Site Footer */
.site-footer {
  margin-top: auto;
  background: #0B1120;
  color: #94A3B8;
  border-top: 1px solid #1E293B;
  padding: 4.5rem 0 2rem;
  font-size: 0.925rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(4, 1fr);
  gap: 2.5rem;
  margin-bottom: 3.5rem;
}

.footer-brand-desc {
  margin-top: 1rem;
  font-size: 0.925rem;
  line-height: 1.6;
  color: #64748B;
  max-width: 320px;
}

.footer-col-title {
  font-family: var(--font-display);
  font-size: 0.875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #F8FAFC;
  margin-bottom: 1.25rem;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-link {
  color: #94A3B8;
  text-decoration: none;
  transition: color 0.15s ease;
}

.footer-link:hover {
  color: #38BDF8;
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid #1E293B;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.875rem;
  color: #64748B;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-bottom-links {
  display: flex;
  gap: 1.5rem;
}

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.2rem 0.6rem;
  font-size: 0.75rem;
  font-weight: 700;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.badge-live {
  background: #DCFCE7;
  color: #15803D;
  border: 1px solid #86EFAC;
}

.badge-beta {
  background: #FEF3C7;
  color: #B45309;
  border: 1px solid #FCD34D;
}

.badge-planned {
  background: #F1F5F9;
  color: #64748B;
  border: 1px solid #CBD5E1;
}

/* Toast Notification */
.toast-container {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 1000;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  pointer-events: none;
}

.toast {
  pointer-events: auto;
  background: #0F172A;
  color: white;
  padding: 0.85rem 1.25rem;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  box-shadow: var(--shadow-xl);
  border: 1px solid #334155;
  animation: toastIn 0.25s ease-out forwards;
}

@keyframes toastIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Media Queries */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 1080px) {
  :root {
    --header-height: 64px;
  }
  
  .nav-desktop {
    display: none;
  }

  .nav-toggle-btn {
    display: block;
  }
}

@media (max-width: 768px) {

  .hero-title {
    font-size: 2rem;
  }

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

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

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }
}