:root {
  --sky: rgb(186, 233, 255);
  --sky-night: rgb(9, 24, 56);
  --glass-bg: rgba(255, 255, 255, 0.3);
  --glass-border: rgba(255, 255, 255, 0.45);
  --text: rgb(34, 53, 74);
  --shadow: rgba(71, 122, 156, 0.18);
  --safe-top: env(safe-area-inset-top, 0px);
  --safe-right: env(safe-area-inset-right, 0px);
  --safe-bottom: env(safe-area-inset-bottom, 0px);
  --safe-left: env(safe-area-inset-left, 0px);
}

* {
  box-sizing: border-box;
}

html,
body {
  width: 100%;
  min-height: 100%;
  overflow-x: hidden;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  position: relative;
  isolation: isolate;
  margin: 0;
  min-height: 100vh;
  min-height: 100dvh;
  overflow: hidden;
  overscroll-behavior: none;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color: var(--text);
  background: none;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  background:
    radial-gradient(circle at top, rgba(255, 255, 255, 0.45), transparent 35%),
    var(--sky);
}

.night-mode body::before {
  background:
    radial-gradient(circle at top, rgba(152, 195, 255, 0.12), transparent 30%),
    linear-gradient(180deg, rgb(12, 30, 68), var(--sky-night));
}

.info-trigger {
  position: fixed;
  top: calc(var(--safe-top) + 64px);
  right: calc(var(--safe-right) + 16px);
  z-index: 3;
  width: 40px;
  height: 40px;
  border: 2px solid #000;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.86);
  color: #000;
  font: 700 1.1rem/1 "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  cursor: pointer;
}

.theme-switch {
  position: fixed;
  top: calc(var(--safe-top) + 16px);
  right: calc(var(--safe-right) + 16px);
  z-index: 3;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border: 2px solid #000;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.86);
  color: #000;
  font: 600 0.92rem/1 "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  cursor: pointer;
  user-select: none;
}

.theme-switch-label {
  white-space: nowrap;
}

.theme-switch-control {
  position: relative;
  display: inline-flex;
  width: 42px;
  height: 24px;
}

.theme-switch-control input {
  position: absolute;
  inset: 0;
  opacity: 0;
  margin: 0;
}

.theme-switch-slider {
  position: absolute;
  inset: 0;
  border: 2px solid #000;
  border-radius: 999px;
  background: rgb(202, 225, 239);
  transition: background 180ms ease;
}

.theme-switch-slider::after {
  content: "";
  position: absolute;
  top: 1px;
  left: 1px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: #fff;
  border: 2px solid #000;
  transition: transform 180ms ease;
}

.theme-switch-control input:checked + .theme-switch-slider {
  background: rgb(26, 48, 96);
}

.theme-switch-control input:checked + .theme-switch-slider::after {
  transform: translateX(18px);
}

.info-popup {
  position: fixed;
  top: calc(var(--safe-top) + 112px);
  right: calc(var(--safe-right) + 16px);
  z-index: 3;
  width: min(320px, calc(100vw - 32px));
  padding: 14px 16px;
  border: 2px solid #000;
  border-radius: 18px;
  background: white;
  box-shadow: 0 16px 30px rgba(0, 0, 0, 0.12);
}

.info-popup p {
  margin: 0;
  line-height: 1.5;
}

.duck-rain {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: auto;
  overflow: hidden;
  contain: layout paint;
  transform: translateZ(0);
  will-change: transform;
}

.duck-drag-layer {
  position: fixed;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  overflow: hidden;
  contain: layout paint;
}

.duck {
  position: absolute;
  top: var(--start-top);
  left: var(--start-left);
  width: calc(var(--size) * 1px);
  opacity: 1;
  filter: drop-shadow(0 7px 12px rgba(255, 255, 255, 0.28));
  animation-name: duck-fall;
  animation-timing-function: linear;
  animation-iteration-count: 1;
  animation-fill-mode: both;
  animation-duration: calc(var(--duration) * 1s);
  animation-delay: calc(var(--delay) * 1s);
  pointer-events: auto;
  touch-action: none;
  user-select: none;
  -webkit-user-drag: none;
  -webkit-touch-callout: none;
  cursor: grab;
  will-change: transform;
  backface-visibility: hidden;
  transform-origin: center;
  transform: translateZ(0);
}

.duck.is-dragged {
  animation: none;
  filter: drop-shadow(0 10px 18px rgba(255, 255, 255, 0.34));
  cursor: grabbing;
  z-index: 999;
}

.page-shell {
  position: fixed;
  inset: 0;
  z-index: 5;
  width: 100%;
  min-height: 100vh;
  min-height: 100dvh;
  display: grid;
  justify-items: center;
  align-content: start;
  overflow-x: hidden;
  overflow-y: auto;
  overscroll-behavior-y: contain;
  -webkit-overflow-scrolling: touch;
  padding:
    calc(var(--safe-top) + 32px)
    calc(var(--safe-right) + 24px)
    calc(var(--safe-bottom) + 32px)
    calc(var(--safe-left) + 24px);
  pointer-events: none;
}

.panel-stack {
  position: relative;
  width: min(1136px, 100%);
  padding-right: 56px;
  pointer-events: none;
}

.glass-card {
  width: 100%;
  padding: 40px;
  border: 1px solid var(--glass-border);
  border-radius: 28px;
  background: var(--glass-bg);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  box-shadow: 0 24px 60px var(--shadow);
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
  gap: 28px;
  transform-origin: center right;
  transition:
    opacity 180ms ease,
    transform 220ms ease,
    filter 220ms ease;
  pointer-events: auto;
  overflow: visible;
  touch-action: pan-y;
}

@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .glass-card {
    background: rgba(255, 255, 255, 0.88);
  }

  .control-group {
    background: rgba(255, 255, 255, 0.62);
  }
}

.card-copy {
  align-self: start;
  min-width: 0;
  touch-action: pan-y;
}

.eyebrow {
  margin: 0 0 12px;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: rgba(34, 53, 74, 0.72);
}

.glass-card h1 {
  margin: 0 0 14px;
  font-size: clamp(2rem, 4vw, 2.8rem);
}

.intro {
  margin: 0;
  font-size: 1.05rem;
  line-height: 1.6;
}

.control-panel {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  align-self: start;
  min-width: 0;
  overflow: visible;
  touch-action: pan-y;
}

.control-group {
  padding: 18px;
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.3);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.18);
  touch-action: pan-y;
}

.control-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 8px;
  font-weight: 600;
}

.control-heading + input {
  margin-bottom: 16px;
}

.control-group label {
  font-size: 0.95rem;
}

.control-group input[type="range"] {
  width: 100%;
  margin: 0;
  accent-color: rgb(34, 53, 74);
}

.value-input {
  width: 96px;
  min-height: 40px;
  padding: 8px 10px;
  border: 1px solid rgba(255, 255, 255, 0.45);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.55);
  color: var(--text);
  font: inherit;
  font-size: 16px;
  text-align: right;
}

.value-input:focus {
  outline: 2px solid rgba(34, 53, 74, 0.22);
  outline-offset: 2px;
}

.collapse-hint {
  grid-column: 1 / -1;
  margin: -6px 0 0;
  text-align: center;
  font-size: 0.92rem;
  color: rgba(34, 53, 74, 0.78);
  touch-action: pan-y;
}

.panel-toggle {
  position: absolute;
  top: 50%;
  right: 0;
  border: 0;
  padding: 0;
  background: transparent;
  cursor: pointer;
  line-height: 1;
  transform: translateY(-50%);
  transition: right 220ms ease;
  pointer-events: auto;
}

.panel-toggle-icon {
  display: inline-block;
  min-width: 44px;
  padding: 10px 6px 12px;
  color: white;
  font-size: 2.35rem;
  font-weight: 700;
  animation: panel-toggle-bounce-right 1.8s ease-in-out infinite;
  text-shadow:
    -2px -2px 0 #000,
    0 -2px 0 #000,
    2px -2px 0 #000,
    -2px 0 0 #000,
    2px 0 0 #000,
    -2px 2px 0 #000,
    0 2px 0 #000,
    2px 2px 0 #000,
    0 3px 12px rgba(0, 0, 0, 0.28);
}

.panel-collapsed .glass-card {
  opacity: 0;
  transform: translateX(64px) scale(0.985);
  filter: blur(3px);
  pointer-events: none;
}

.panel-collapsed .collapse-hint {
  opacity: 0;
}

.panel-collapsed .panel-toggle-icon {
  animation-name: panel-toggle-bounce-left;
}

.panel-collapsed .panel-toggle {
  position: fixed;
  top: 50vh;
  right: 14px;
}

@keyframes duck-fall {
  0% {
    transform:
      translate3d(var(--drift-start), 0, 0)
      rotate(var(--rotate-start))
      scale(var(--scale-start));
  }

  50% {
    transform:
      translate3d(var(--drift-mid), var(--fall-mid), 0)
      rotate(var(--rotate-mid))
      scale(var(--scale-mid));
  }

  100% {
    transform:
      translate3d(var(--drift-end), var(--fall-end), 0)
      rotate(var(--rotate-end))
      scale(var(--scale-end));
  }
}

@keyframes panel-toggle-bounce-right {
  0%,
  100% {
    transform: translate3d(0, 0, 0) scale(1);
  }

  18% {
    transform: translate3d(4px, 0, 0) scale(1.04);
  }

  34% {
    transform: translate3d(0, 0, 0) scale(0.98);
  }

  52% {
    transform: translate3d(9px, 0, 0) scale(1.08);
  }

  70% {
    transform: translate3d(0, 0, 0) scale(0.99);
  }
}

@keyframes panel-toggle-bounce-left {
  0%,
  100% {
    transform: translate3d(0, 0, 0) scale(1);
  }

  18% {
    transform: translate3d(-4px, 0, 0) scale(1.04);
  }

  34% {
    transform: translate3d(0, 0, 0) scale(0.98);
  }

  52% {
    transform: translate3d(-9px, 0, 0) scale(1.08);
  }

  70% {
    transform: translate3d(0, 0, 0) scale(0.99);
  }
}

@media (max-width: 920px) {
  .glass-card {
    grid-template-columns: 1fr;
  }

  .control-panel {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  .panel-toggle-icon {
    animation: none;
  }

  .glass-card,
  .panel-toggle,
  .theme-switch-slider,
  .theme-switch-slider::after {
    transition-duration: 0.01ms;
  }
}

@media (max-width: 640px) {
  .info-trigger {
    top: calc(var(--safe-top) + 56px);
    right: calc(var(--safe-right) + 12px);
    width: 36px;
    height: 36px;
  }

  .info-popup {
    top: calc(var(--safe-top) + 104px);
    right: calc(var(--safe-right) + 12px);
    width: min(300px, calc(100vw - var(--safe-left) - var(--safe-right) - 24px));
  }

  .theme-switch {
    top: calc(var(--safe-top) + 12px);
    right: calc(var(--safe-right) + 12px);
    gap: 8px;
    padding: 7px 10px;
    font-size: 0.84rem;
    max-width: min(220px, calc(100vw - var(--safe-left) - var(--safe-right) - 24px));
  }

  .page-shell {
    padding:
      calc(var(--safe-top) + 112px)
      calc(var(--safe-right) + 18px)
      calc(var(--safe-bottom) + 22px)
      calc(var(--safe-left) + 18px);
  }

  .glass-card,
  .card-copy,
  .control-panel,
  .control-group,
  .collapse-hint {
    touch-action: pan-y;
  }

  .panel-stack {
    width: 100%;
    max-width: 100%;
    padding-right: 42px;
  }

  .glass-card {
    width: 100%;
    max-width: 100%;
    padding: 24px;
    gap: 22px;
    display: flex;
    flex-direction: column;
  }

  .card-copy {
    flex-shrink: 0;
  }

  .control-panel {
    flex: 0 0 auto;
  }

  .collapse-hint {
    margin-top: 12px;
    flex-shrink: 0;
  }

  .panel-toggle-icon {
    min-width: 34px;
    font-size: 1.95rem;
  }

  .panel-toggle {
    position: fixed;
    top: 50vh;
    left: auto;
    right: calc(var(--safe-right) + 10px);
    transform: translateY(-50%);
  }
}

@media (max-width: 420px) {
  .theme-switch {
    gap: 6px;
    padding: 6px 9px;
  }

  .theme-switch-label {
    font-size: 0.79rem;
  }

  .glass-card {
    padding: 20px;
    border-radius: 24px;
  }

  .control-group {
    padding: 15px;
    border-radius: 18px;
  }

  .control-heading {
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
  }

  .value-input {
    width: 100%;
    text-align: left;
  }

  .panel-stack {
    padding-right: 38px;
  }
}