/* ============================================
   VIDEO DOWNLOADER - CSS MODERNO E RESPONSIVO
   ============================================ */

/* ============================================
   CSS CUSTOM PROPERTIES (VARIÁVEIS)
   ============================================ */
:root {
  /* Cores principais */
  --color-primary: #6366f1;
  --color-primary-dark: #4f46e5;
  --color-primary-light: #818cf8;
  --color-secondary: #10b981;
  --color-secondary-dark: #059669;
  
  /* Cores neutras */
  --color-white: #ffffff;
  --color-gray-50: #f9fafb;
  --color-gray-100: #f3f4f6;
  --color-gray-200: #e5e7eb;
  --color-gray-300: #d1d5db;
  --color-gray-400: #9ca3af;
  --color-gray-500: #6b7280;
  --color-gray-600: #4b5563;
  --color-gray-700: #374151;
  --color-gray-800: #1f2937;
  --color-gray-900: #111827;
  
  /* Cores de estado */
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;
  --color-info: #3b82f6;
  
  /* Tipografia */
  --font-family-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  --font-family-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, 'Courier New', monospace;
  
  /* Tamanhos de fonte */
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  
  /* Pesos de fonte */
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  /* Espaçamento */
  --spacing-1: 0.25rem;
  --spacing-2: 0.5rem;
  --spacing-3: 0.75rem;
  --spacing-4: 1rem;
  --spacing-5: 1.25rem;
  --spacing-6: 1.5rem;
  --spacing-8: 2rem;
  --spacing-10: 2.5rem;
  --spacing-12: 3rem;
  --spacing-16: 4rem;
  --spacing-20: 5rem;
  
  /* Bordas */
  --border-radius-sm: 0.25rem;
  --border-radius-md: 0.375rem;
  --border-radius-lg: 0.5rem;
  --border-radius-xl: 0.75rem;
  --border-radius-2xl: 1rem;
  --border-radius-full: 9999px;
  
  /* Sombras */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  
  /* Transições */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;
  
  /* Layout */
  --container-max-width: 1200px;
  --container-padding: var(--spacing-4);
  
  /* Z-index */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
}

/* ============================================
   DARK MODE SUPPORT
   ============================================ */
@media (prefers-color-scheme: dark) {
  :root {
    --color-white: #0f172a;
    --color-gray-50: #1e293b;
    --color-gray-100: #334155;
    --color-gray-200: #475569;
    --color-gray-300: #64748b;
    --color-gray-400: #94a3b8;
    --color-gray-500: #cbd5e1;
    --color-gray-600: #e2e8f0;
    --color-gray-700: #f1f5f9;
    --color-gray-800: #f8fafc;
    --color-gray-900: #ffffff;
    
    --color-primary: #818cf8;
    --color-primary-dark: #6366f1;
    --color-primary-light: #a5b4fc;
  }
}

/* ============================================
   RESET E BASE
   ============================================ */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  line-height: 1.5;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family-primary);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  color: var(--color-gray-800);
  background-color: var(--color-gray-50);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

.hidden {
  display: none !important;
}

/* ============================================
   LAYOUT
   ============================================ */
.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: var(--container-padding);
  flex: 1;
  display: flex;
  flex-direction: column;
}

/* ============================================
   HEADER
   ============================================ */
.header {
  padding: var(--spacing-8) 0 var(--spacing-6);
  text-align: center;
  animation: fadeInDown 0.6s ease-out;
}

.header__content {
  max-width: 600px;
  margin: 0 auto;
}

.header__logo {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-3);
  margin-bottom: var(--spacing-4);
}

.header__icon {
  width: 3rem;
  height: 3rem;
  color: var(--color-primary);
}

.header__title {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-gray-900);
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header__subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-gray-600);
  font-weight: var(--font-weight-medium);
}

/* ============================================
   MAIN CONTENT
   ============================================ */
.main {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-8);
}

/* ============================================
   CARDS
   ============================================ */
.card {
  background: var(--color-white);
  border-radius: var(--border-radius-xl);
  box-shadow: var(--shadow-lg);
  padding: var(--spacing-8);
  animation: fadeInUp 0.6s ease-out;
  transition: transform var(--transition-normal);
}

.card:hover {
  transform: translateY(-2px);
}

.card__title {
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  margin-bottom: var(--spacing-2);
}

.card__description {
  color: var(--color-gray-600);
  margin-bottom: var(--spacing-6);
}

.card--info {
  background: linear-gradient(135deg, var(--color-gray-50) 0%, var(--color-white) 100%);
  border: 1px solid var(--color-gray-200);
}

/* ============================================
   FORMS
   ============================================ */
.download-form {
  margin-bottom: var(--spacing-6);
}

.form-group {
  margin-bottom: var(--spacing-6);
}

.form-label {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-700);
  margin-bottom: var(--spacing-2);
}

.input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.form-input {
  width: 100%;
  padding: var(--spacing-4) var(--spacing-12) var(--spacing-4) var(--spacing-4);
  font-size: var(--font-size-base);
  font-family: var(--font-family-primary);
  color: var(--color-gray-900);
  background: var(--color-white);
  border: 2px solid var(--color-gray-300);
  border-radius: var(--border-radius-lg);
  transition: all var(--transition-fast);
}

.form-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.form-input::placeholder {
  color: var(--color-gray-400);
}

.form-input:invalid {
  border-color: var(--color-error);
}

.form-help {
  display: block;
  font-size: var(--font-size-xs);
  color: var(--color-gray-500);
  margin-top: var(--spacing-2);
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-2);
  padding: var(--spacing-3) var(--spacing-6);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  font-family: var(--font-family-primary);
  color: var(--color-white);
  background: var(--color-primary);
  border: none;
  border-radius: var(--border-radius-lg);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
  user-select: none;
}

.btn:hover {
  background: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.3);
}

.btn:active {
  transform: translateY(0);
}

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

.btn--primary:hover {
  background: var(--color-primary-dark);
}

.btn--large {
  padding: var(--spacing-4) var(--spacing-8);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
}

.btn--icon {
  padding: var(--spacing-2);
  background: transparent;
  color: var(--color-gray-500);
  position: absolute;
  right: var(--spacing-2);
  top: 50%;
  transform: translateY(-50%);
}

.btn--icon:hover {
  background: var(--color-gray-100);
  color: var(--color-gray-700);
  transform: translateY(-50%);
}

.btn--clear {
  border-radius: var(--border-radius-full);
}

.btn--ghost {
  background: transparent;
  color: var(--color-gray-500);
  position: static;
  transform: none;
}

.btn--ghost:hover {
  background: var(--color-gray-100);
  color: var(--color-gray-700);
  transform: none;
}

.btn__text {
  order: 1;
}

.btn__icon {
  width: 1.25rem;
  height: 1.25rem;
  order: 2;
}

.form-actions {
  display: flex;
  justify-content: center;
  margin-top: var(--spacing-8);
}

/* ============================================
   PREVIEW SECTION
   ============================================ */
.preview-section {
  margin-top: var(--spacing-8);
  padding-top: var(--spacing-8);
  border-top: 1px solid var(--color-gray-200);
  animation: fadeIn 0.3s ease-out;
}

.preview__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--spacing-4);
}

.preview__title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
}

.preview__content {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-4);
}

.preview__video {
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-md);
}

.preview__info {
  padding: var(--spacing-4);
  background: var(--color-gray-50);
  border-radius: var(--border-radius-md);
  font-size: var(--font-size-sm);
  color: var(--color-gray-600);
}

/* ============================================
   PROGRESS SECTION
   ============================================ */
.progress-section {
  margin-top: var(--spacing-8);
  padding: var(--spacing-6);
  background: var(--color-gray-50);
  border-radius: var(--border-radius-lg);
  animation: fadeIn 0.3s ease-out;
}

.progress__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--spacing-4);
}

.progress__title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-900);
}

.progress__status {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-primary);
}

.progress__bar {
  width: 100%;
  height: 8px;
  background: var(--color-gray-200);
  border-radius: var(--border-radius-full);
  overflow: hidden;
  margin-bottom: var(--spacing-3);
}

.progress__fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  border-radius: var(--border-radius-full);
  transition: width var(--transition-normal);
  width: 0%;
}

.progress__info {
  font-size: var(--font-size-sm);
  color: var(--color-gray-600);
  text-align: center;
}

/* ============================================
   INFO SECTION
   ============================================ */
.info-section {
  animation: fadeInUp 0.8s ease-out;
}

.info-list {
  list-style: none;
  counter-reset: info-counter;
  margin-bottom: var(--spacing-6);
}

.info-item {
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-4);
  margin-bottom: var(--spacing-4);
  counter-increment: info-counter;
}

.info__number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  background: var(--color-primary);
  color: var(--color-white);
  border-radius: var(--border-radius-full);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  flex-shrink: 0;
}

.info__number::before {
  content: counter(info-counter);
}

.info__content {
  flex: 1;
  color: var(--color-gray-700);
}

.info__content strong {
  color: var(--color-gray-900);
}

.info__warning {
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-3);
  padding: var(--spacing-4);
  background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
  border: 1px solid #f59e0b;
  border-radius: var(--border-radius-lg);
  color: #92400e;
}

.info__icon {
  width: 1.5rem;
  height: 1.5rem;
  color: #f59e0b;
  flex-shrink: 0;
}

.info__warning p {
  margin: 0;
  font-size: var(--font-size-sm);
}

.info__warning strong {
  color: #92400e;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  margin-top: auto;
  padding: var(--spacing-8) 0 var(--spacing-4);
  text-align: center;
  color: var(--color-gray-500);
}

.footer__content {
  max-width: 600px;
  margin: 0 auto;
}

.footer__text {
  font-size: var(--font-size-sm);
  margin-bottom: var(--spacing-2);
}

.footer__note {
  font-size: var(--font-size-xs);
  color: var(--color-gray-400);
}

/* ============================================
   ANIMATIONS
   ============================================ */
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

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

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

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

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

/* Mobile First - Default styles above */

/* Tablet (768px and up) */
@media (min-width: 768px) {
  :root {
    --container-padding: var(--spacing-8);
  }
  
  .container {
    padding: var(--spacing-8);
  }
  
  .header {
    padding: var(--spacing-12) 0 var(--spacing-8);
  }
  
  .header__title {
    font-size: var(--font-size-4xl);
  }
  
  .card {
    padding: var(--spacing-12);
  }
  
  .preview__content {
    flex-direction: row;
    align-items: flex-start;
  }
  
  .preview__video {
    flex: 1;
    max-width: 60%;
  }
  
  .preview__info {
    flex: 0 0 35%;
  }
}

/* Desktop (1024px and up) */
@media (min-width: 1024px) {
  .header__title {
    font-size: 3rem;
  }
  
  .main {
    flex-direction: row;
    gap: var(--spacing-12);
  }
  
  .download-section {
    flex: 2;
  }
  
  .info-section {
    flex: 1;
  }
  
  .card {
    padding: var(--spacing-16);
  }
}

/* Large Desktop (1280px and up) */
@media (min-width: 1280px) {
  .container {
    max-width: 1400px;
  }
  
  .header {
    padding: var(--spacing-16) 0 var(--spacing-12);
  }
}

/* ============================================
   HIGH CONTRAST MODE
   ============================================ */
@media (prefers-contrast: high) {
  :root {
    --color-gray-300: #000000;
    --color-gray-600: #000000;
    --color-gray-900: #000000;
  }
  
  .form-input {
    border-width: 3px;
  }
  
  .btn {
    border: 2px solid currentColor;
  }
}

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