/* ==========================================================================
   REHAN ASADI DESIGN SYSTEM
   Modern, conversion-focused, minimalist design system for rehanasadi.com
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&family=DM+Mono:ital,wght@0,400;0,500;1,400&family=Caveat:wght@500;600&display=swap');

:root {
  /* Surface & Backgrounds */
  --ds-bg: #FFFFFF;
  --ds-surface: #FFFFFF;
  --ds-surface-subtle: #F8FAFC;
  --ds-surface-muted: #F1F5F9;
  --ds-surface-dark: #0F172A;
  --ds-surface-card: #FFFFFF;
  --ds-surface-green-tint: #F2F8F5;

  /* Borders */
  --ds-border: #E5E7EB;
  --ds-border-subtle: #F3F4F6;
  --ds-border-strong: #CBD5E1;
  --ds-border-green: #D1E7DD;

  /* Typography / Text Colors */
  --ds-text: #0F172A;
  --ds-text-secondary: #475569;
  --ds-text-muted: #64748B;
  --ds-text-light: #94A3B8;
  --ds-text-inverse: #FFFFFF;

  /* Accent Color (Forest / Emerald Green) */
  --ds-accent: #155E49;
  --ds-accent-hover: #0F4736;
  --ds-accent-light: #EBF7F2;
  --ds-accent-border: #A7F3D0;
  --ds-accent-text: #0F5132;
  --ds-accent-tint: rgba(21, 94, 73, 0.08);

  /* Functional Status */
  --ds-success: #16A34A;
  --ds-success-bg: #DCFCE7;
  --ds-success-text: #15803D;

  /* Typography Families */
  --ds-font-sans: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --ds-font-mono: 'DM Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  --ds-font-script: 'Caveat', cursive, sans-serif;

  /* Typography Scale */
  --ds-text-xs: 0.75rem;     /* 12px */
  --ds-text-sm: 0.875rem;    /* 14px */
  --ds-text-base: 1rem;      /* 16px */
  --ds-text-lg: 1.125rem;    /* 18px */
  --ds-text-xl: 1.25rem;     /* 20px */
  --ds-text-2xl: 1.5rem;     /* 24px */
  --ds-text-3xl: 1.875rem;   /* 30px */
  --ds-text-4xl: 2.25rem;    /* 36px */
  --ds-text-5xl: 3rem;       /* 48px */
  --ds-text-6xl: 3.75rem;    /* 60px */

  /* Border Radii */
  --ds-radius-xs: 4px;
  --ds-radius-sm: 8px;
  --ds-radius-md: 12px;
  --ds-radius-lg: 16px;
  --ds-radius-xl: 20px;
  --ds-radius-full: 9999px;

  /* Shadows */
  --ds-shadow-sm: 0 1px 2px 0 rgba(16, 24, 40, 0.04);
  --ds-shadow-card: 0 1px 3px 0 rgba(16, 24, 40, 0.06), 0 1px 2px -1px rgba(16, 24, 40, 0.04);
  --ds-shadow-md: 0 4px 8px -2px rgba(16, 24, 40, 0.06), 0 2px 4px -2px rgba(16, 24, 40, 0.03);
  --ds-shadow-hover: 0 12px 24px -4px rgba(16, 24, 40, 0.08), 0 4px 6px -2px rgba(16, 24, 40, 0.03);
  --ds-shadow-lg: 0 20px 30px -6px rgba(16, 24, 40, 0.1), 0 8px 10px -4px rgba(16, 24, 40, 0.04);

  /* Layout & Widths */
  --ds-max-width: 1200px;
  --ds-container-px: 1.5rem;
  --ds-section-py: 5rem;
  --ds-section-py-sm: 3.5rem;
}

/* ==========================================================================
   CSS RESET & CORE DEFAULTS
   ========================================================================== */

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--ds-bg);
  color: var(--ds-text);
  font-family: var(--ds-font-sans);
  font-size: var(--ds-text-base);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img, svg, picture {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.15s ease;
}

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

/* ==========================================================================
   CONTAINER & SECTION LAYOUT
   ========================================================================== */

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

.ds-section {
  padding-top: var(--ds-section-py);
  padding-bottom: var(--ds-section-py);
  position: relative;
}

.ds-section-subtle {
  background-color: var(--ds-surface-subtle);
  border-top: 1px solid var(--ds-border-subtle);
  border-bottom: 1px solid var(--ds-border-subtle);
}

.ds-section-border {
  border-bottom: 1px solid var(--ds-border);
}

/* Section Header Structure */
.ds-section-header {
  margin-bottom: 3rem;
}

.ds-section-header-split {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 2rem;
  margin-bottom: 3rem;
}

.ds-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: var(--ds-text-xs);
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ds-accent);
  margin-bottom: 0.85rem;
}

.ds-eyebrow-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--ds-accent);
}

.ds-title {
  font-size: var(--ds-text-3xl);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.025em;
  color: var(--ds-text);
}

@media (min-width: 768px) {
  .ds-title {
    font-size: var(--ds-text-4xl);
  }
}

.ds-desc {
  font-size: var(--ds-text-base);
  color: var(--ds-text-secondary);
  line-height: 1.7;
  max-width: 600px;
}

.ds-header-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: var(--ds-text-sm);
  font-weight: 600;
  color: var(--ds-text);
  white-space: nowrap;
  transition: color 0.15s ease, transform 0.15s ease;
}

.ds-header-link:hover {
  color: var(--ds-accent);
  transform: translateX(2px);
}

/* ==========================================================================
   BUTTONS
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--ds-font-sans);
  font-size: var(--ds-text-sm);
  font-weight: 600;
  line-height: 1;
  padding: 0.75rem 1.4rem;
  border-radius: var(--ds-radius-full);
  border: 1px solid transparent;
  transition: all 0.18s ease;
  white-space: nowrap;
  text-decoration: none;
}

.btn-primary {
  background-color: var(--ds-accent);
  color: #FFFFFF;
  border-color: var(--ds-accent);
  box-shadow: 0 1px 2px rgba(21, 94, 73, 0.15);
}

.btn-primary:hover {
  background-color: var(--ds-accent-hover);
  border-color: var(--ds-accent-hover);
  color: #FFFFFF;
  box-shadow: 0 4px 12px rgba(21, 94, 73, 0.25);
  transform: translateY(-1px);
}

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

.btn-secondary:hover {
  background-color: var(--ds-surface-subtle);
  border-color: var(--ds-border-strong);
  color: var(--ds-text);
  transform: translateY(-1px);
}

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

.btn-ghost:hover {
  color: var(--ds-text);
  background-color: var(--ds-surface-subtle);
}

.btn-icon-arrow {
  display: inline-block;
  transition: transform 0.18s ease;
}

.btn:hover .btn-icon-arrow {
  transform: translateX(3px);
}

/* ==========================================================================
   CARDS & CONTAINERS
   ========================================================================== */

.ds-card {
  background-color: var(--ds-surface-card);
  border: 1px solid var(--ds-border);
  border-radius: var(--ds-radius-lg);
  padding: 2rem;
  box-shadow: var(--ds-shadow-card);
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
}

.ds-card:hover {
  box-shadow: var(--ds-shadow-hover);
  border-color: var(--ds-border-strong);
  transform: translateY(-2px);
}

.ds-card-subtle {
  background-color: var(--ds-surface-subtle);
  border: 1px solid var(--ds-border);
  border-radius: var(--ds-radius-lg);
  padding: 1.75rem;
}

/* Badges / Tags */
.ds-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: var(--ds-text-xs);
  font-weight: 600;
  padding: 0.3rem 0.75rem;
  border-radius: var(--ds-radius-full);
  line-height: 1.2;
}

.ds-badge-green {
  background-color: var(--ds-accent-light);
  color: var(--ds-accent-text);
  border: 1px solid var(--ds-accent-border);
}

.ds-badge-neutral {
  background-color: var(--ds-surface-muted);
  color: var(--ds-text-secondary);
  border: 1px solid var(--ds-border);
}

/* ==========================================================================
   NAVIGATION (HEADER)
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--ds-border);
}

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

.site-logo {
  font-size: 1.15rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--ds-text);
  display: inline-flex;
  align-items: center;
}

.site-logo span {
  color: var(--ds-accent);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.site-nav a {
  font-size: var(--ds-text-sm);
  font-weight: 500;
  color: var(--ds-text-secondary);
  transition: color 0.15s ease;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--ds-text);
  font-weight: 600;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* Mobile Nav Toggle */
.mobile-nav-toggle {
  display: none;
  padding: 0.5rem;
  color: var(--ds-text);
  border-radius: var(--ds-radius-sm);
}

.mobile-nav-toggle:focus-visible {
  outline: 2px solid var(--ds-accent);
}

.mobile-nav-drawer {
  display: none;
  background: #FFFFFF;
  border-bottom: 1px solid var(--ds-border);
  padding: 1.5rem;
}

.mobile-nav-drawer.is-open {
  display: block;
}

.mobile-nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.mobile-nav-list a {
  font-size: var(--ds-text-base);
  font-weight: 600;
  color: var(--ds-text);
  display: block;
  padding: 0.35rem 0;
}

/* ==========================================================================
   ACCORDION (FAQ)
   ========================================================================== */

.ds-accordion-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 860px;
  margin: 0 auto;
}

.ds-accordion-item {
  background-color: #FFFFFF;
  border: 1px solid var(--ds-border);
  border-radius: var(--ds-radius-md);
  overflow: hidden;
  transition: border-color 0.18s ease, box-shadow 0.18s ease;
}

.ds-accordion-item[open] {
  border-color: var(--ds-border-strong);
  box-shadow: var(--ds-shadow-sm);
}

.ds-accordion-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 1.5rem;
  font-size: var(--ds-text-base);
  font-weight: 700;
  color: var(--ds-text);
  cursor: pointer;
  list-style: none;
  user-select: none;
}

.ds-accordion-summary::-webkit-details-marker {
  display: none;
}

.ds-accordion-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background-color: var(--ds-surface-subtle);
  color: var(--ds-text-secondary);
  font-size: 16px;
  font-weight: 600;
  line-height: 1;
  transition: transform 0.2s ease, background-color 0.2s ease, color 0.2s ease;
}

.ds-accordion-item[open] .ds-accordion-icon {
  transform: rotate(45deg);
  background-color: var(--ds-accent-light);
  color: var(--ds-accent-text);
}

.ds-accordion-body {
  padding: 0 1.5rem 1.5rem;
  font-size: var(--ds-text-sm);
  color: var(--ds-text-secondary);
  line-height: 1.75;
}

/* ==========================================================================
   FOOTER
   ========================================================================== */

.site-footer {
  background-color: #FFFFFF;
  border-top: 1px solid var(--ds-border);
  padding: 4.5rem 0 2.5rem;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1fr 1fr;
  gap: 3.5rem;
  margin-bottom: 3.5rem;
}

.footer-brand p {
  color: var(--ds-text-secondary);
  font-size: var(--ds-text-sm);
  line-height: 1.7;
  margin-top: 0.85rem;
  max-width: 320px;
}

.footer-col h4 {
  font-size: var(--ds-text-xs);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ds-text);
  margin-bottom: 1.25rem;
}

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

.footer-links a {
  font-size: var(--ds-text-sm);
  color: var(--ds-text-secondary);
  transition: color 0.15s ease;
}

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

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 2rem;
  border-top: 1px solid var(--ds-border-subtle);
  font-size: var(--ds-text-xs);
  color: var(--ds-text-muted);
}

.footer-socials {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.footer-socials a {
  color: var(--ds-text-muted);
  font-size: var(--ds-text-xs);
  font-weight: 500;
  transition: color 0.15s ease;
}

.footer-socials a:hover {
  color: var(--ds-text);
}

/* ==========================================================================
   RESPONSIVE UTILITIES & BREAKPOINTS
   ========================================================================== */

@media (max-width: 1024px) {
  :root {
    --ds-section-py: 4rem;
  }
  .footer-top {
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem;
  }
}

@media (max-width: 768px) {
  :root {
    --ds-section-py: 3.5rem;
    --ds-container-px: 1.25rem;
  }
  .site-nav {
    display: none;
  }
  .mobile-nav-toggle {
    display: block;
  }
  .ds-section-header-split {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
  }
  .footer-top {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
}