/* ============================================
   SHARED DESIGN SYSTEM
   Sites: ai-services, trading-signals, portfolio
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
  /* Colors */
  --color-bg:           #0a0a0f;
  --color-bg-alt:       #12121a;
  --color-bg-card:      #16161f;
  --color-bg-elevated:  #1c1c28;
  --color-border:       #2a2a3a;
  --color-border-light: #3a3a4a;

  --color-text:         #e8e8ef;
  --color-text-muted:   #9a9ab0;
  --color-text-dim:     #6a6a80;

  --color-primary:      #6366f1;
  --color-primary-light:#818cf8;
  --color-primary-dark: #4f46e5;

  --color-accent:       #a855f7;
  --color-accent-light: #c084fc;

  --color-success:      #22c55e;
  --color-warning:      #f59e0b;
  --color-danger:       #ef4444;

  /* Gradients */
  --gradient-primary:   linear-gradient(135deg, #6366f1, #a855f7);
  --gradient-hero:      linear-gradient(135deg, #6366f1 0%, #a855f7 50%, #ec4899 100%);
  --gradient-card:      linear-gradient(135deg, rgba(99,102,241,0.1), rgba(168,85,247,0.1));
  --gradient-glow:      radial-gradient(600px circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(99,102,241,0.08), transparent 40%);

  /* Typography */
  --font-body:    'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-heading: 'Space Grotesk', 'Inter', sans-serif;
  --font-mono:    'JetBrains Mono', 'Fira Code', monospace;

  --text-xs:   0.75rem;
  --text-sm:   0.875rem;
  --text-base: 1rem;
  --text-lg:   1.125rem;
  --text-xl:   1.25rem;
  --text-2xl:  1.5rem;
  --text-3xl:  1.875rem;
  --text-4xl:  2.25rem;
  --text-5xl:  3rem;
  --text-6xl:  3.75rem;

  --leading-tight:  1.2;
  --leading-normal: 1.6;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Layout */
  --max-width:   1200px;
  --max-width-sm: 640px;
  --max-width-md: 768px;
  --max-width-lg: 1024px;

  /* Borders */
  --radius-sm:  0.375rem;
  --radius-md:  0.5rem;
  --radius-lg:  0.75rem;
  --radius-xl:  1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm:  0 1px 2px rgba(0,0,0,0.3);
  --shadow-md:  0 4px 6px rgba(0,0,0,0.3);
  --shadow-lg:  0 10px 15px rgba(0,0,0,0.4);
  --shadow-xl:  0 20px 25px rgba(0,0,0,0.5);
  --shadow-glow: 0 0 40px rgba(99,102,241,0.3);

  /* Transitions */
  --transition-fast:   150ms ease;
  --transition-base:   250ms ease;
  --transition-slow:   400ms ease;
  --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);
}


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

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

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

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

a {
  color: var(--color-primary-light);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

ul, ol {
  list-style: none;
}

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


/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: var(--leading-tight);
  color: var(--color-text);
}

h1 { font-size: var(--text-5xl); }
h2 { font-size: var(--text-4xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }

@media (max-width: 768px) {
  h1 { font-size: var(--text-4xl); }
  h2 { font-size: var(--text-3xl); }
  h3 { font-size: var(--text-xl); }
}

.text-gradient {
  background: var(--gradient-hero);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

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

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


/* --- Layout --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.section {
  padding: var(--space-20) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-16);
}

.section-header h2 {
  margin-bottom: var(--space-4);
}

.section-header p {
  color: var(--color-text-muted);
  font-size: var(--text-lg);
  max-width: 600px;
  margin: 0 auto;
}

.grid {
  display: grid;
  gap: var(--space-6);
}

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

@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  .grid-2,
  .grid-3,
  .grid-4 { grid-template-columns: 1fr; }
}


/* --- Navigation --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: var(--space-4) 0;
  background: rgba(10, 10, 15, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid transparent;
  transition: all var(--transition-base);
}

.nav.scrolled {
  border-bottom-color: var(--color-border);
  background: rgba(10, 10, 15, 0.95);
}

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

.nav-logo {
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
}

.nav-logo span {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.nav-links a {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  font-weight: 500;
  transition: color var(--transition-fast);
}

.nav-links a:hover {
  color: var(--color-text);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  transition: all var(--transition-base);
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    bottom: 0;
    flex-direction: column;
    justify-content: flex-start;
    padding-top: var(--space-10);
    gap: var(--space-6);
    background: rgba(10, 10, 15, 0.98);
    backdrop-filter: blur(20px);
    transform: translateX(100%);
    transition: transform var(--transition-base);
  }

  .nav-links.open {
    transform: translateX(0);
  }

  .nav-links a {
    font-size: var(--text-lg);
  }
}


/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: 600;
  border: none;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-base);
  white-space: nowrap;
  text-decoration: none;
}

.btn-primary {
  background: var(--gradient-primary);
  color: #fff;
  box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(99, 102, 241, 0.4);
  color: #fff;
}

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

.btn-secondary:hover {
  border-color: var(--color-primary);
  background: rgba(99, 102, 241, 0.1);
  color: var(--color-text);
}

.btn-lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-base);
  border-radius: var(--radius-xl);
}

.btn-sm {
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-xs);
}


/* --- Cards --- */
.card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition-base);
}

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

.card:hover::before {
  opacity: 1;
}

.card-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-card);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-4);
  font-size: var(--text-2xl);
}

.card h3 {
  margin-bottom: var(--space-3);
}

.card p {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
}


/* --- Pricing Cards --- */
.pricing-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  text-align: center;
  transition: all var(--transition-base);
  position: relative;
}

.pricing-card.featured {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-glow);
}

.pricing-card.featured::before {
  content: 'Most Popular';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translate(-50%, -50%);
  background: var(--gradient-primary);
  color: #fff;
  font-size: var(--text-xs);
  font-weight: 600;
  padding: var(--space-1) var(--space-4);
  border-radius: var(--radius-full);
}

.pricing-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-primary);
}

.pricing-card .price {
  font-family: var(--font-heading);
  font-size: var(--text-5xl);
  font-weight: 700;
  margin: var(--space-4) 0;
}

.pricing-card .price span {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  font-weight: 400;
}

.pricing-card .features {
  text-align: left;
  margin: var(--space-8) 0;
}

.pricing-card .features li {
  padding: var(--space-2) 0;
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.pricing-card .features li::before {
  content: '';
  width: 18px;
  height: 18px;
  min-width: 18px;
  border-radius: 50%;
  background: rgba(34, 197, 94, 0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(34, 197, 94, 0.3);
}


/* --- Forms --- */
.form-group {
  margin-bottom: var(--space-4);
}

.form-group label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 500;
  margin-bottom: var(--space-2);
  color: var(--color-text-muted);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text);
  transition: all var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.form-textarea {
  resize: vertical;
  min-height: 120px;
}

.form-input::placeholder,
.form-textarea::placeholder {
  color: var(--color-text-dim);
}


/* --- Badges / Tags --- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--space-1) var(--space-3);
  font-size: var(--text-xs);
  font-weight: 600;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.badge-primary {
  background: rgba(99, 102, 241, 0.15);
  color: var(--color-primary-light);
  border: 1px solid rgba(99, 102, 241, 0.3);
}

.badge-success {
  background: rgba(34, 197, 94, 0.15);
  color: var(--color-success);
  border: 1px solid rgba(34, 197, 94, 0.3);
}

.badge-warning {
  background: rgba(245, 158, 11, 0.15);
  color: var(--color-warning);
  border: 1px solid rgba(245, 158, 11, 0.3);
}


/* --- Testimonials --- */
.testimonial {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
}

.testimonial-text {
  color: var(--color-text-muted);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  margin-bottom: var(--space-6);
  font-style: italic;
}

.testimonial-text::before {
  content: '"';
  font-size: var(--text-4xl);
  color: var(--color-primary);
  font-family: Georgia, serif;
  line-height: 0;
  vertical-align: -0.4em;
  margin-right: 4px;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.testimonial-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: var(--text-sm);
  color: #fff;
}

.testimonial-name {
  font-weight: 600;
  font-size: var(--text-sm);
}

.testimonial-role {
  font-size: var(--text-xs);
  color: var(--color-text-dim);
}


/* --- Hero Section --- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  padding-top: 80px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 0;
}

.hero-bg::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 30% 40%, rgba(99,102,241,0.08) 0%, transparent 50%),
              radial-gradient(circle at 70% 60%, rgba(168,85,247,0.06) 0%, transparent 50%);
  animation: heroBgFloat 20s ease-in-out infinite;
}

@keyframes heroBgFloat {
  0%, 100% { transform: translate(0, 0); }
  33% { transform: translate(2%, -1%); }
  66% { transform: translate(-1%, 2%); }
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 720px;
}

.hero h1 {
  margin-bottom: var(--space-6);
}

.hero p {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  margin-bottom: var(--space-8);
  max-width: 560px;
}

.hero-actions {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
}

.hero-stats {
  display: flex;
  gap: var(--space-10);
  margin-top: var(--space-12);
  flex-wrap: wrap;
}

.hero-stat {
  text-align: left;
}

.hero-stat .number {
  font-family: var(--font-heading);
  font-size: var(--text-3xl);
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-stat .label {
  font-size: var(--text-sm);
  color: var(--color-text-dim);
  margin-top: var(--space-1);
}


/* --- FAQ / Accordion --- */
.faq-item {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-3);
  overflow: hidden;
}

.faq-question {
  width: 100%;
  padding: var(--space-5) var(--space-6);
  background: var(--color-bg-card);
  border: none;
  color: var(--color-text);
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background var(--transition-fast);
}

.faq-question:hover {
  background: var(--color-bg-elevated);
}

.faq-question::after {
  content: '+';
  font-size: var(--text-xl);
  color: var(--color-primary);
  transition: transform var(--transition-base);
}

.faq-item.open .faq-question::after {
  content: '-';
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow);
}

.faq-answer-inner {
  padding: 0 var(--space-6) var(--space-5);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
}


/* --- Footer --- */
.footer {
  padding: var(--space-16) 0 var(--space-8);
  border-top: 1px solid var(--color-border);
  background: var(--color-bg-alt);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-10);
  margin-bottom: var(--space-10);
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }
}

.footer-brand p {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  margin-top: var(--space-3);
  max-width: 300px;
}

.footer h4 {
  font-size: var(--text-sm);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-dim);
  margin-bottom: var(--space-4);
}

.footer-links li {
  margin-bottom: var(--space-2);
}

.footer-links a {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}

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

.footer-bottom {
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.footer-bottom p {
  color: var(--color-text-dim);
  font-size: var(--text-sm);
}


/* --- Animations --- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.animate-on-scroll.visible {
  opacity: 1;
  transform: translateY(0);
}

.animate-delay-1 { transition-delay: 0.1s; }
.animate-delay-2 { transition-delay: 0.2s; }
.animate-delay-3 { transition-delay: 0.3s; }
.animate-delay-4 { transition-delay: 0.4s; }


/* --- Utility Classes --- */
.text-center { text-align: center; }
.text-left   { text-align: left; }
.text-right  { text-align: right; }

.flex         { display: flex; }
.flex-col     { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: var(--space-2); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

.mt-4  { margin-top: var(--space-4); }
.mt-6  { margin-top: var(--space-6); }
.mt-8  { margin-top: var(--space-8); }
.mt-12 { margin-top: var(--space-12); }
.mb-4  { margin-bottom: var(--space-4); }
.mb-6  { margin-bottom: var(--space-6); }
.mb-8  { margin-bottom: var(--space-8); }

.w-full { width: 100%; }
.relative { position: relative; }
.overflow-hidden { overflow: hidden; }

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}


/* --- Scrollbar --- */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-bg);
}

::-webkit-scrollbar-thumb {
  background: var(--color-border-light);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-dim);
}


/* --- Selection --- */
::selection {
  background: rgba(99, 102, 241, 0.3);
  color: #fff;
}