/**
 * Opers Academy - Main CSS
 * Global styles and utility classes
 */

/* ============================================
   CSS VARIABLES
   ============================================ */

:root {
  /* Colors */
  --color-primary: #3b82f6;
  --color-primary-dark: #2563eb;
  --color-secondary: #8b5cf6;
  --color-secondary-dark: #7c3aed;
  --color-accent: #06b6d4;
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
  --gradient-secondary: linear-gradient(135deg, #8b5cf6 0%, #ec4899 100%);
  --gradient-blue: linear-gradient(135deg, #3b82f6 0%, #06b6d4 100%);
  --gradient-purple: linear-gradient(135deg, #8b5cf6 0%, #ec4899 100%);
  --gradient-orange: linear-gradient(135deg, #f97316 0%, #ef4444 100%);
  --gradient-green: linear-gradient(135deg, #10b981 0%, #059669 100%);
  --gradient-yellow: linear-gradient(135deg, #f59e0b 0%, #f97316 100%);
  --gradient-gold: linear-gradient(135deg, #fcd34d 0%, #f59e0b 100%);

  /* Background */
  --bg-primary: #000000;
  --bg-secondary: #0f0f0f;
  --bg-tertiary: #1a1a1a;
  --bg-card: rgba(255, 255, 255, 0.05);
  --bg-card-hover: rgba(255, 255, 255, 0.1);

  /* Text */
  --text-primary: #ffffff;
  --text-secondary: #a1a1aa;
  --text-tertiary: #71717a;

  /* Border */
  --border-color: rgba(255, 255, 255, 0.1);
  --border-color-light: rgba(255, 255, 255, 0.05);

  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;

  /* Border Radius */
  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-2xl: 2rem;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --shadow-glow-blue: 0 0 30px rgba(59, 130, 246, 0.3);
  --shadow-glow-purple: 0 0 30px rgba(139, 92, 246, 0.3);
  --shadow-glow-cyan: 0 0 30px rgba(6, 182, 212, 0.3);

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 300ms ease-in-out;
  --transition-slow: 500ms ease-in-out;

  /* Z-index */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Oxygen, Ubuntu, Cantarell, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-primary);
  overflow-x: hidden;
}

/* Selection */
::selection {
  background: var(--color-primary);
  color: white;
}

::-moz-selection {
  background: var(--color-primary);
  color: white;
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 10px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--bg-tertiary);
  border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.2);
}

/* ============================================
   TYPOGRAPHY
   ============================================ */

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

h1 {
  font-size: clamp(2rem, 5vw, 4rem);
}
h2 {
  font-size: clamp(1.75rem, 4vw, 3rem);
}
h3 {
  font-size: clamp(1.5rem, 3vw, 2.25rem);
}
h4 {
  font-size: clamp(1.25rem, 2.5vw, 1.75rem);
}
h5 {
  font-size: 1.25rem;
}
h6 {
  font-size: 1rem;
}

p {
  margin-bottom: 1rem;
  color: var(--text-secondary);
}

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

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

strong {
  font-weight: 600;
  color: var(--text-primary);
}

/* ============================================
   LAYOUT
   ============================================ */

.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.container-sm {
  max-width: 768px;
}

.container-lg {
  max-width: 1536px;
}

section {
  padding: 5rem 0;
  position: relative;
}

@media (max-width: 768px) {
  section {
    padding: 3rem 0;
  }
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1;
  text-align: center;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
  white-space: nowrap;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* Button Sizes */
.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

.btn-block {
  width: 100%;
}

/* Button Variants */
.btn-primary {
  background: var(--gradient-primary);
  color: white;
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow-blue);
  color: white;
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  color: white;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.2);
}

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

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-primary);
}

.btn-success {
  background: var(--color-success);
  color: white;
}

.btn-success:hover {
  background: #059669;
}

.btn-danger {
  background: var(--color-error);
  color: white;
}

.btn-danger:hover {
  background: #dc2626;
}

/* ============================================
   CARDS
   ============================================ */

.card {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 1.5rem;
  transition: all var(--transition-base);
}

.card:hover {
  background: var(--bg-card-hover);
  transform: translateY(-4px);
}

/* ============================================
   GRADIENTS
   ============================================ */

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

.gradient-blue {
  background: var(--gradient-blue);
}

.gradient-purple {
  background: var(--gradient-purple);
}

.gradient-orange {
  background: var(--gradient-orange);
}

.gradient-green {
  background: var(--gradient-green);
}

.gradient-yellow {
  background: var(--gradient-yellow);
}

.gradient-gold {
  background: var(--gradient-gold);
}

/* ============================================
   UTILITIES
   ============================================ */

/* Text Colors */
.text-primary {
  color: var(--text-primary);
}
.text-secondary {
  color: var(--text-secondary);
}
.text-tertiary {
  color: var(--text-tertiary);
}
.text-cyan {
  color: var(--color-accent);
}
.text-success {
  color: var(--color-success);
}
.text-warning {
  color: var(--color-warning);
}
.text-error {
  color: var(--color-error);
}

/* Text Alignment */
.text-left {
  text-align: left;
}
.text-center {
  text-align: center;
}
.text-right {
  text-align: right;
}

/* Font Weights */
.font-light {
  font-weight: 300;
}
.font-normal {
  font-weight: 400;
}
.font-medium {
  font-weight: 500;
}
.font-semibold {
  font-weight: 600;
}
.font-bold {
  font-weight: 700;
}
.font-extrabold {
  font-weight: 800;
}

/* Display */
.block {
  display: block;
}
.inline-block {
  display: inline-block;
}
.flex {
  display: flex;
}
.inline-flex {
  display: inline-flex;
}
.grid {
  display: grid;
}
.hidden {
  display: none;
}

/* Flex */
.flex-row {
  flex-direction: row;
}
.flex-col {
  flex-direction: column;
}
.items-center {
  align-items: center;
}
.items-start {
  align-items: flex-start;
}
.items-end {
  align-items: flex-end;
}
.justify-center {
  justify-content: center;
}
.justify-between {
  justify-content: space-between;
}
.justify-around {
  justify-content: space-around;
}
.flex-wrap {
  flex-wrap: wrap;
}
.gap-1 {
  gap: 0.25rem;
}
.gap-2 {
  gap: 0.5rem;
}
.gap-3 {
  gap: 0.75rem;
}
.gap-4 {
  gap: 1rem;
}
.gap-6 {
  gap: 1.5rem;
}
.gap-8 {
  gap: 2rem;
}

/* Spacing */
.m-0 {
  margin: 0;
}
.mt-1 {
  margin-top: 0.25rem;
}
.mt-2 {
  margin-top: 0.5rem;
}
.mt-4 {
  margin-top: 1rem;
}
.mt-8 {
  margin-top: 2rem;
}
.mb-1 {
  margin-bottom: 0.25rem;
}
.mb-2 {
  margin-bottom: 0.5rem;
}
.mb-4 {
  margin-bottom: 1rem;
}
.mb-8 {
  margin-bottom: 2rem;
}
.mx-auto {
  margin-left: auto;
  margin-right: auto;
}

.p-0 {
  padding: 0;
}
.p-2 {
  padding: 0.5rem;
}
.p-4 {
  padding: 1rem;
}
.p-6 {
  padding: 1.5rem;
}
.p-8 {
  padding: 2rem;
}

/* Width */
.w-full {
  width: 100%;
}
.w-auto {
  width: auto;
}
.max-w-full {
  max-width: 100%;
}

/* Position */
.relative {
  position: relative;
}
.absolute {
  position: absolute;
}
.fixed {
  position: fixed;
}
.sticky {
  position: sticky;
}

/* Overflow */
.overflow-hidden {
  overflow: hidden;
}
.overflow-auto {
  overflow: auto;
}

/* Opacity */
.opacity-0 {
  opacity: 0;
}
.opacity-50 {
  opacity: 0.5;
}
.opacity-100 {
  opacity: 1;
}

/* Transitions */
.transition {
  transition: all var(--transition-base);
}
.transition-fast {
  transition: all var(--transition-fast);
}
.transition-slow {
  transition: all var(--transition-slow);
}

/* Shadows */
.shadow-sm {
  box-shadow: var(--shadow-sm);
}
.shadow-md {
  box-shadow: var(--shadow-md);
}
.shadow-lg {
  box-shadow: var(--shadow-lg);
}
.shadow-xl {
  box-shadow: var(--shadow-xl);
}

/* Border Radius */
.rounded {
  border-radius: var(--radius-md);
}
.rounded-lg {
  border-radius: var(--radius-lg);
}
.rounded-xl {
  border-radius: var(--radius-xl);
}
.rounded-2xl {
  border-radius: var(--radius-2xl);
}
.rounded-full {
  border-radius: 9999px;
}

/* Backdrop Filter */
.backdrop-blur {
  backdrop-filter: blur(10px);
}

/* Highlights */
.highlight-cyan {
  color: var(--color-accent);
  font-weight: 600;
}

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

@keyframes slideIn {
  from {
    transform: translateX(-100%);
  }
  to {
    transform: translateX(0);
  }
}

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

@keyframes spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

@keyframes float {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-20px);
  }
}

/* Animation Classes */
.animate-fade-in {
  animation: fadeIn 0.8s ease-out forwards;
}

.animate-fade-in-delay-1 {
  animation: fadeIn 0.8s ease-out 0.2s forwards;
  opacity: 0;
}

.animate-fade-in-delay-2 {
  animation: fadeIn 0.8s ease-out 0.4s forwards;
  opacity: 0;
}

.animate-fade-in-delay-3 {
  animation: fadeIn 0.8s ease-out 0.6s forwards;
  opacity: 0;
}

.animate-fade-in-delay-4 {
  animation: fadeIn 0.8s ease-out 0.8s forwards;
  opacity: 0;
}

.animate-pulse {
  animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

.animate-spin {
  animation: spin 1s linear infinite;
}

.animate-float {
  animation: float 3s ease-in-out infinite;
}

/* ============================================
   FORMS
   ============================================ */

.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--text-primary);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  line-height: 1.5;
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  transition: var(--transition-base);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  outline: none;
  border-color: var(--color-primary);
  background: rgba(255, 255, 255, 0.08);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

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

.form-error {
  color: var(--color-error);
  font-size: 0.875rem;
  margin-top: 0.25rem;
}

.form-help {
  color: var(--text-tertiary);
  font-size: 0.875rem;
  margin-top: 0.25rem;
}

/* ============================================
   ALERTS
   ============================================ */

.alert {
  padding: 1rem 1.5rem;
  border-radius: var(--radius-md);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.alert-success {
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid var(--color-success);
  color: var(--color-success);
}

.alert-error {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid var(--color-error);
  color: var(--color-error);
}

.alert-warning {
  background: rgba(245, 158, 11, 0.1);
  border: 1px solid var(--color-warning);
  color: var(--color-warning);
}

.alert-info {
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid var(--color-primary);
  color: var(--color-primary);
}

/* ============================================
   BADGES
   ============================================ */

.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: 9999px;
}

.badge-primary {
  background: rgba(59, 130, 246, 0.2);
  color: var(--color-primary);
}

.badge-success {
  background: rgba(16, 185, 129, 0.2);
  color: var(--color-success);
}

.badge-warning {
  background: rgba(245, 158, 11, 0.2);
  color: var(--color-warning);
}

.badge-error {
  background: rgba(239, 68, 68, 0.2);
  color: var(--color-error);
}

/* ============================================
   LOADER
   ============================================ */

.loader {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 0.6s linear infinite;
}

.loader-lg {
  width: 40px;
  height: 40px;
  border-width: 4px;
}

/* Loading overlay */
.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.8);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal);
}

/* ============================================
   MODAL
   ============================================ */

.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: var(--z-modal);
}

.modal.active {
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.8);
  backdrop-filter: blur(4px);
}

.modal-content {
  position: relative;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  max-width: 600px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
  z-index: calc(var(--z-modal) + 1);
}

.modal-close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: rgba(255, 255, 255, 0.1);
  border: none;
  border-radius: 50%;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition-base);
  color: var(--text-secondary);
}

.modal-close:hover {
  background: rgba(255, 255, 255, 0.2);
  color: var(--text-primary);
}

.modal-body {
  padding: 2rem;
}

/* ============================================
   RESPONSIVE
   ============================================ */

@media (max-width: 1024px) {
  .container {
    padding: 0 1rem;
  }

  h1 {
    font-size: 2.5rem;
  }
  h2 {
    font-size: 2rem;
  }
  h3 {
    font-size: 1.75rem;
  }
}

@media (max-width: 768px) {
  body {
    font-size: 14px;
  }

  .btn {
    padding: 0.625rem 1.25rem;
  }

  .btn-lg {
    padding: 0.875rem 1.75rem;
    font-size: 1rem;
  }

  section {
    padding: 2.5rem 0;
  }

  .modal-content {
    width: 95%;
    max-height: 85vh;
  }

  .modal-body {
    padding: 1.5rem;
  }
}

@media (max-width: 640px) {
  .container {
    padding: 0 0.75rem;
  }

  h1 {
    font-size: 2rem;
  }
  h2 {
    font-size: 1.75rem;
  }
  h3 {
    font-size: 1.5rem;
  }

  .btn {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
  }
}

/* ============================================
   ACCESSIBILITY
   ============================================ */

/* Focus visible for keyboard navigation */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Skip to main content link */
.skip-to-main {
  position: absolute;
  left: -9999px;
  z-index: 999;
  padding: 1em;
  background-color: var(--color-primary);
  color: white;
  text-decoration: none;
}

.skip-to-main:focus {
  left: 50%;
  transform: translateX(-50%);
  top: 1rem;
}

/* Screen reader only */
.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;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ============================================
   PRINT STYLES
   ============================================ */

@media print {
  body {
    background: white;
    color: black;
  }

  .navbar,
  .footer,
  .modal,
  .btn {
    display: none !important;
  }

  a {
    text-decoration: underline;
  }

  .container {
    max-width: 100%;
  }
}