:root {
  /* Easing curves */
  --ease-out: cubic-bezier(0.23, 1, 0.32, 1);
  --ease-in-out: cubic-bezier(0.77, 0, 0.175, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);

  /* Colors */
  --bg: #0a0a0f;
  --surface: #14141b;
  --surface-hover: #1c1c26;
  --text-primary: #f0f0f5;
  --text-secondary: #8a8a9a;
  --danger: #ff4455;
  --danger-soft: rgba(255, 68, 85, 0.15);
  --success: #00dd88;
  --success-soft: rgba(0, 221, 136, 0.15);

  /* Dimensions */
  --track-height: 56px;
  --thumb-size: 44px;
  --thumb-gap: 6px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  -webkit-font-smoothing: antialiased;
}

.container {
  width: 100%;
  max-width: 480px;
  animation: containerEnter 600ms var(--ease-out) forwards;
  opacity: 0;
  transform: translateY(12px);
}

@keyframes containerEnter {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.header {
  text-align: center;
  margin-bottom: 48px;
  animation: headerEnter 500ms var(--ease-out) 100ms forwards;
  opacity: 0;
  transform: translateY(8px);
}

@keyframes headerEnter {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.title {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 8px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  font-size: 15px;
  color: var(--text-secondary);
  font-weight: 400;
}

.sliders {
  display: flex;
  flex-direction: column;
  gap: 32px;
  margin-bottom: 40px;
}

.slider-card {
  background: var(--surface);
  border-radius: 20px;
  padding: 24px;
  border: 1px solid rgba(255, 255, 255, 0.04);
  animation: cardEnter 500ms var(--ease-out) forwards;
  opacity: 0;
  transform: translateY(12px);
}

.slider-card:nth-child(1) {
  animation-delay: 200ms;
}

.slider-card:nth-child(2) {
  animation-delay: 280ms;
}

@keyframes cardEnter {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.slider-labels {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
  padding: 0 4px;
}

.label {
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  transition: color 200ms var(--ease-out);
  user-select: none;
}

.label-left {
  color: var(--danger);
}

.label-right {
  color: var(--text-secondary);
}

.slider-card[data-active="true"] .label-left {
  color: var(--text-secondary);
}

.slider-card[data-active="true"] .label-right {
  color: var(--success);
}

.slider-track {
  position: relative;
  width: 100%;
  height: var(--track-height);
  background: var(--danger-soft);
  border-radius: calc(var(--track-height) / 2);
  border: none;
  cursor: pointer;
  padding: 0;
  overflow: hidden;
  transition: transform 160ms var(--ease-out), background 250ms var(--ease-out);
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

.slider-track:hover {
  background: rgba(255, 68, 85, 0.22);
}

.slider-track:active {
  transform: scale(0.98);
}

.slider-card[data-active="true"] .slider-track {
  background: var(--success-soft);
}

.slider-card[data-active="true"] .slider-track:hover {
  background: rgba(0, 221, 136, 0.22);
}

.slider-fill {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  width: 100%;
  background: linear-gradient(90deg, var(--danger) 0%, #ff6677 100%);
  border-radius: calc(var(--track-height) / 2);
  transform: translateX(-100%);
  transition: transform 350ms var(--ease-spring), background 300ms var(--ease-out);
  opacity: 0.9;
}

.slider-card[data-active="true"] .slider-fill {
  transform: translateX(0);
  background: linear-gradient(90deg, #00cc7a 0%, var(--success) 100%);
}

.slider-thumb {
  position: absolute;
  top: var(--thumb-gap);
  left: var(--thumb-gap);
  width: var(--thumb-size);
  height: var(--thumb-size);
  background: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.25), 0 1px 3px rgba(0, 0, 0, 0.15);
  transform: translateX(0);
  transition: transform 350ms var(--ease-spring), box-shadow 200ms var(--ease-out);
  z-index: 2;
}

.slider-card[data-active="true"] .slider-thumb {
  transform: translateX(var(--slide-distance, 0px));
  box-shadow: 0 2px 16px rgba(0, 221, 136, 0.3), 0 1px 3px rgba(0, 0, 0, 0.15);
}

.thumb-icon {
  position: relative;
  width: 20px;
  height: 20px;
}

.thumb-icon svg {
  position: absolute;
  top: 0;
  left: 0;
  width: 20px;
  height: 20px;
  transition: opacity 200ms var(--ease-out), transform 200ms var(--ease-out);
}

.icon-left {
  color: var(--danger);
  opacity: 1;
  transform: scale(1) rotate(0deg);
}

.icon-right {
  color: var(--success);
  opacity: 0;
  transform: scale(0.8) rotate(-45deg);
}

.slider-card[data-active="true"] .icon-left {
  opacity: 0;
  transform: scale(0.8) rotate(45deg);
}

.slider-card[data-active="true"] .icon-right {
  opacity: 1;
  transform: scale(1) rotate(0deg);
}

.status {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  font-size: 14px;
  color: var(--text-secondary);
  animation: statusEnter 500ms var(--ease-out) 360ms forwards;
  opacity: 0;
  transform: translateY(8px);
}

@keyframes statusEnter {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--text-secondary);
  transition: background 200ms var(--ease-out), box-shadow 200ms var(--ease-out);
}

.status[data-state="danger"] .status-dot {
  background: var(--danger);
  box-shadow: 0 0 8px rgba(255, 68, 85, 0.4);
}

.status[data-state="success"] .status-dot {
  background: var(--success);
  box-shadow: 0 0 8px rgba(0, 221, 136, 0.4);
}

.status-text {
  font-weight: 500;
  transition: color 200ms var(--ease-out);
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  .container,
  .header,
  .slider-card,
  .status {
    animation: none;
    opacity: 1;
    transform: none;
  }

  .slider-fill,
  .slider-thumb {
    transition-duration: 50ms;
  }
}

/* Touch device hover fix */
@media (hover: hover) and (pointer: fine) {
  .slider-track:hover {
    transform: scale(1.01);
  }

  .slider-track:active {
    transform: scale(0.98);
  }
}