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

:root {
  /* Color Palette - Minimal & Professional */
  --color-white: #ffffff;
  --color-gray-50: #fafafa;
  --color-gray-100: #f5f5f5;
  --color-gray-200: #e5e5e5;
  --color-gray-300: #d4d4d4;
  --color-gray-400: #a3a3a3;
  --color-gray-500: #737373;
  --color-gray-600: #525252;
  --color-gray-700: #404040;
  --color-gray-800: #262626;
  --color-gray-900: #171717;
  
  /* Accent Color - Subtle Blue */
  --color-primary: #3b82f6;
  --color-primary-hover: #2563eb;
  --color-primary-light: #dbeafe;
  
  /* Functional Colors */
  --color-success: #10b981;
  --color-error: #ef4444;
  --color-warning: #f59e0b;
  
  /* Spacing System */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  
  /* 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), 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);
  
  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, 'Courier New', monospace;
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  line-height: 1.6;
  color: var(--color-gray-700);
  background-color: var(--color-gray-50);
  min-height: 100vh;
}

/* ==========================================
   LAYOUT
   ========================================== */
.app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.main {
  flex: 1;
  padding: var(--space-xl) var(--space-md);
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
}

/* ==========================================
   HEADER
   ========================================== */
.header {
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-gray-200);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.header__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-md) var(--space-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
}

.brand {
  display: flex;
  align-items: center;
  text-decoration: none;
  transition: opacity var(--transition-fast);
}

.brand:hover {
  opacity: 0.8;
}

.brand__logo {
  height: 32px;
  width: auto;
  display: block;
}

.header__right {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* ==========================================
   HERO SECTION
   ========================================== */
.hero__title {
  font-size: 2.25rem;
  font-weight: 700;
  color: var(--color-gray-900);
  letter-spacing: -0.025em;
  line-height: 1.2;
  margin-bottom: var(--space-md);
  text-align: center;
}

.hero__subtitle {
  font-size: 1.125rem;
  color: var(--color-gray-600);
  text-align: center;
  margin-bottom: var(--space-2xl);
  font-weight: 400;
}

/* ==========================================
   PANEL
   ========================================== */
.panel {
  background-color: var(--color-white);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--color-gray-200);
  overflow: hidden;
  max-width: 720px;
  margin: 0 auto;
  transition: opacity var(--transition-base), transform var(--transition-base);
}

.panel[data-hidden="1"] {
  opacity: 0;
  transform: translateY(8px);
  pointer-events: none;
}

.panel__head {
  padding: var(--space-xl) var(--space-xl) var(--space-lg);
  border-bottom: 1px solid var(--color-gray-200);
  background-color: var(--color-gray-50);
}

.panel__title {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--color-gray-900);
  margin-bottom: var(--space-xs);
  letter-spacing: -0.015em;
}

.panel__desc {
  font-size: 0.875rem;
  color: var(--color-gray-600);
  font-weight: 400;
}

.panel__body {
  padding: var(--space-xl);
}

/* ==========================================
   BUTTONS
   ========================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.625rem 1.25rem;
  font-size: 0.9375rem;
  font-weight: 500;
  line-height: 1.5;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-sans);
  text-decoration: none;
  white-space: nowrap;
}

.btn:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

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

.btn--primary {
  background-color: var(--color-gray-900);
  color: var(--color-white);
  border-color: var(--color-gray-900);
}

.btn--primary:hover:not(:disabled) {
  background-color: var(--color-gray-800);
  border-color: var(--color-gray-800);
}

.btn--primary:active:not(:disabled) {
  transform: scale(0.98);
}

.btn--ghost {
  background-color: transparent;
  color: var(--color-gray-700);
  border-color: var(--color-gray-300);
}

.btn--ghost:hover:not(:disabled) {
  background-color: var(--color-gray-100);
  border-color: var(--color-gray-400);
}

/* ==========================================
   DROPZONE
   ========================================== */
.dropzone {
  border: 2px dashed var(--color-gray-300);
  border-radius: var(--radius-lg);
  padding: var(--space-3xl) var(--space-xl);
  text-align: center;
  cursor: pointer;
  transition: all var(--transition-base);
  background-color: var(--color-gray-50);
}

.dropzone:hover {
  border-color: var(--color-gray-400);
  background-color: var(--color-white);
}

.dropzone:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-color: var(--color-primary);
}

.dropzone.is-dragover {
  border-color: var(--color-primary);
  background-color: var(--color-primary-light);
}

.dropzone__icon {
  width: 48px;
  height: 48px;
  margin: 0 auto var(--space-lg);
  color: var(--color-gray-400);
}

.dropzone:hover .dropzone__icon {
  color: var(--color-gray-600);
}

.icon {
  width: 100%;
  height: 100%;
  display: block;
}

.dropzone__text {
  margin-bottom: var(--space-sm);
}

.dropzone__title {
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-gray-900);
  margin-bottom: var(--space-xs);
}

.dropzone__hint {
  font-size: 0.875rem;
  color: var(--color-gray-500);
}

/* ==========================================
   FILE INFO
   ========================================== */
.fileline {
  margin-top: var(--space-lg);
  padding: var(--space-md) var(--space-lg);
  background-color: var(--color-gray-50);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-gray-200);
}

.fileline__name {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-gray-900);
  margin-bottom: var(--space-xs);
  word-break: break-word;
}

.fileline__sub {
  font-size: 0.8125rem;
  color: var(--color-gray-600);
}

/* ==========================================
   PROGRESS & STATUS
   ========================================== */
.status {
  margin-top: var(--space-lg);
}

.progress {
  height: 8px;
  background-color: var(--color-gray-200);
  border-radius: 999px;
  overflow: hidden;
  margin-bottom: var(--space-md);
}

.progress__bar {
  height: 100%;
  background-color: var(--color-gray-900);
  transition: width var(--transition-base);
  border-radius: 999px;
}

.status__row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-md);
}

.status__label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-gray-700);
}

.status__value {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-gray-900);
  font-variant-numeric: tabular-nums;
}

/* ==========================================
   ALERTS
   ========================================== */
.alert {
  margin-top: var(--space-lg);
  padding: var(--space-md) var(--space-lg);
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  line-height: 1.5;
  border: 1px solid;
}

.alert.alert--error {
  background-color: #fef2f2;
  border-color: #fecaca;
  color: #991b1b;
}

.alert.alert--success {
  background-color: #f0fdf4;
  border-color: #bbf7d0;
  color: #166534;
}

.alert.alert--warning {
  background-color: #fffbeb;
  border-color: #fde68a;
  color: #92400e;
}

/* ==========================================
   RESULT SECTION
   ========================================== */
.result {
  margin-top: var(--space-xl);
  padding: var(--space-lg);
  background-color: var(--color-gray-50);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-gray-200);
}

.result__title {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-gray-900);
  margin-bottom: var(--space-md);
}

.result__row {
  display: flex;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.result__actions {
  display: flex;
  justify-content: flex-end;
  gap: var(--space-sm);
}

/* ==========================================
   INPUT FIELDS
   ========================================== */
.input {
  flex: 1;
  padding: 0.625rem 0.875rem;
  font-size: 0.875rem;
  font-family: var(--font-mono);
  color: var(--color-gray-700);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-300);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.input:focus {
  outline: none;
  border-color: var(--color-gray-900);
  box-shadow: 0 0 0 3px rgba(0, 0, 0, 0.05);
}

.input:read-only {
  background-color: var(--color-gray-50);
  cursor: default;
}

/* ==========================================
   SKELETON LOADING
   ========================================== */
.skeleton {
  max-width: 720px;
  margin: 0 auto;
  padding: var(--space-xl);
  background-color: var(--color-white);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--color-gray-200);
}

.skeleton[hidden] {
  display: none;
}

.skeleton__line,
.skeleton__box {
  background: linear-gradient(
    90deg,
    var(--color-gray-200) 0%,
    var(--color-gray-100) 50%,
    var(--color-gray-200) 100%
  );
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s ease-in-out infinite;
  border-radius: var(--radius-sm);
}

.skeleton__line {
  height: 12px;
  margin-bottom: var(--space-md);
}

.skeleton__line.w60 {
  width: 60%;
}

.skeleton__line.w80 {
  width: 80%;
}

.skeleton__line.w90 {
  width: 90%;
}

.skeleton__box {
  height: 200px;
  margin: var(--space-xl) 0;
  border-radius: var(--radius-lg);
}

@keyframes skeleton-loading {
  0% {
    background-position: 200% 0;
  }
  100% {
    background-position: -200% 0;
  }
}

/* ==========================================
   FOOTER
   ========================================== */
.footer {
  background-color: var(--color-white);
  border-top: 1px solid var(--color-gray-200);
  margin-top: auto;
}

.footer__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-lg);
  text-align: center;
  font-size: 0.875rem;
  color: var(--color-gray-500);
}

/* ==========================================
   UTILITIES
   ========================================== */
[hidden] {
  display: none !important;
}

/* ==========================================
   RESPONSIVE
   ========================================== */
@media (max-width: 640px) {
  .hero__title {
    font-size: 1.75rem;
  }
  
  .hero__subtitle {
    font-size: 1rem;
  }
  
  .panel__head {
    padding: var(--space-lg) var(--space-md);
  }
  
  .panel__body {
    padding: var(--space-lg) var(--space-md);
  }
  
  .panel__title {
    font-size: 1.25rem;
  }
  
  .dropzone {
    padding: var(--space-xl) var(--space-lg);
  }
  
  .dropzone__icon {
    width: 40px;
    height: 40px;
  }
  
  .result__row {
    flex-direction: column;
  }
  
  .result__actions {
    justify-content: stretch;
  }
  
  .btn {
    width: 100%;
  }
}

@media (min-width: 641px) and (max-width: 1024px) {
  .main {
    padding: var(--space-xl) var(--space-lg);
  }
}


/*WATCH VIDEO CSS*/