:root {
  color-scheme: dark;
  --board-ink: #0d1d17;
  --board-deep: #12251d;
  --board: #172d23;
  --board-lift: #1d3428;
  --chalk: #e8e4d4;
  --chalk-muted: #c8c7b8;
  --door-light: #fff2c2;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  min-width: 100%;
  min-height: 100%;
  background: var(--board-ink);
  font-family: "Segoe UI", Arial, sans-serif;
}

body {
  min-width: 100%;
  min-height: 100vh;
  margin: 0;
  background: var(--board-ink);
  color: var(--chalk);
}

.site-main {
  min-height: 100vh;
}

body:not(.landing-page) .site-main {
  width: min(100% - 3rem, 68rem);
  margin-inline: auto;
  padding-block: clamp(3rem, 9vw, 7rem);
  line-height: 1.65;
}

body:not(.landing-page) h1,
body:not(.landing-page) h2,
body:not(.landing-page) h3 {
  color: var(--chalk);
  line-height: 1.15;
}

body:not(.landing-page) a {
  color: #f0d89b;
}

.landing-page {
  overflow: hidden;
}

.blackboard {
  position: relative;
  isolation: isolate;
  width: 100%;
  min-height: 100vh;
  min-height: 100svh;
  height: 100vh;
  height: 100dvh;
  overflow: hidden;
  background:
    radial-gradient(ellipse 86% 48% at 41% -5%, rgba(95, 116, 96, 0.11), rgba(36, 58, 46, 0.025) 48%, transparent 76%),
    radial-gradient(ellipse 42% 72% at -8% 43%, rgba(59, 83, 67, 0.085), transparent 72%),
    radial-gradient(ellipse 54% 82% at 108% 49%, rgba(3, 14, 10, 0.24), transparent 77%),
    radial-gradient(ellipse 66% 28% at 48% 102%, rgba(2, 13, 9, 0.23), transparent 73%),
    linear-gradient(176deg, var(--board-lift) 0%, #193027 26%, var(--board) 55%, var(--board-deep) 82%, #102119 100%);
}

.blackboard::after {
  position: absolute;
  z-index: 12;
  inset: 0;
  content: "";
  pointer-events: none;
  background:
    radial-gradient(ellipse 46% 58% at -7% -9%, rgba(0, 5, 3, 0.32), transparent 69%),
    radial-gradient(ellipse 42% 61% at 108% 1%, rgba(0, 5, 3, 0.28), transparent 71%),
    radial-gradient(ellipse 58% 43% at 94% 111%, rgba(0, 3, 2, 0.36), transparent 72%),
    linear-gradient(90deg, rgba(0, 4, 2, 0.21), transparent 10%, transparent 88%, rgba(0, 4, 2, 0.24)),
    linear-gradient(180deg, rgba(0, 3, 2, 0.08), transparent 14%, transparent 79%, rgba(0, 3, 2, 0.26));
  box-shadow:
    inset 0 0 clamp(4rem, 9vw, 10rem) rgba(0, 4, 2, 0.22),
    inset 0 -2rem 5rem rgba(0, 3, 2, 0.12);
}

.blackboard__surface,
.blackboard__residue,
.blackboard__wipes,
.blackboard__scratches {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.blackboard__surface {
  z-index: 0;
  opacity: 0.42;
  background-image: url("../images/blackboard-grain.svg");
  background-position: 7% 13%;
  background-size: 743px 587px;
  mix-blend-mode: soft-light;
}

.blackboard__surface::before,
.blackboard__surface::after {
  position: absolute;
  content: "";
  pointer-events: none;
}

.blackboard__surface::before {
  inset: -7%;
  opacity: 0.66;
  background:
    radial-gradient(ellipse 31% 18% at 16% 22%, rgba(156, 168, 145, 0.08), transparent 72%),
    radial-gradient(ellipse 43% 13% at 67% 11%, rgba(146, 160, 138, 0.064), transparent 74%),
    radial-gradient(ellipse 36% 22% at 82% 49%, rgba(126, 143, 122, 0.047), transparent 73%),
    radial-gradient(ellipse 48% 18% at 23% 69%, rgba(138, 151, 130, 0.05), transparent 75%),
    radial-gradient(ellipse 32% 24% at 63% 89%, rgba(4, 14, 10, 0.14), transparent 75%);
  filter: blur(14px);
  transform: rotate(-0.35deg);
}

.blackboard__surface::after {
  inset: -9%;
  opacity: 0.28;
  background-image: url("../images/blackboard-grain.svg");
  background-position: 61% 37%;
  background-size: 977px 719px;
  mix-blend-mode: overlay;
  transform: rotate(0.21deg) scale(1.03);
}

.blackboard__residue {
  z-index: 1;
  opacity: 0.72;
  background:
    radial-gradient(ellipse 39% 7% at 19% 15%, rgba(224, 225, 207, 0.052), transparent 74%),
    radial-gradient(ellipse 52% 10% at 64% 8%, rgba(214, 218, 198, 0.04), transparent 75%),
    radial-gradient(ellipse 37% 8% at 81% 27%, rgba(213, 218, 198, 0.035), transparent 77%),
    radial-gradient(ellipse 44% 11% at 14% 43%, rgba(219, 220, 202, 0.04), transparent 75%),
    radial-gradient(ellipse 48% 9% at 73% 56%, rgba(211, 216, 196, 0.033), transparent 74%),
    radial-gradient(ellipse 36% 12% at 31% 72%, rgba(224, 223, 205, 0.044), transparent 75%),
    radial-gradient(ellipse 42% 8% at 77% 82%, rgba(207, 214, 194, 0.033), transparent 74%),
    radial-gradient(ellipse 30% 11% at 22% 94%, rgba(3, 13, 9, 0.12), transparent 75%);
  filter: blur(5px);
}

.blackboard__wipes {
  z-index: 1;
  inset: 1.5% 1%;
  opacity: 0.2;
  background:
    linear-gradient(179deg, transparent 38%, rgba(226, 229, 210, 0.16) 48%, rgba(202, 210, 191, 0.06) 53%, transparent 63%) 6% 12% / 31% 3.5% no-repeat,
    linear-gradient(177.8deg, transparent 40%, rgba(218, 223, 203, 0.13) 48%, transparent 60%) 58% 19% / 35% 3% no-repeat,
    linear-gradient(180.6deg, transparent 39%, rgba(211, 218, 198, 0.12) 49%, transparent 61%) 17% 60% / 28% 2.8% no-repeat,
    linear-gradient(178.4deg, transparent 40%, rgba(222, 225, 207, 0.11) 49%, transparent 60%) 67% 69% / 24% 2.3% no-repeat,
    linear-gradient(176.9deg, transparent 41%, rgba(208, 215, 196, 0.1) 49%, transparent 59%) 36% 90% / 38% 2.5% no-repeat;
  filter: blur(0.65px);
  transform: rotate(-0.11deg);
}

.blackboard__scratches {
  z-index: 1;
  inset: 2.5% 2%;
  opacity: 0.13;
  background:
    linear-gradient(178.5deg, transparent 46%, rgba(232, 232, 214, 0.3) 49%, transparent 53%) 11% 25% / 18% 1.3% no-repeat,
    linear-gradient(181.2deg, transparent 45%, rgba(220, 225, 205, 0.26) 49%, transparent 54%) 46% 16% / 27% 1.1% no-repeat,
    linear-gradient(177.1deg, transparent 45%, rgba(229, 230, 211, 0.22) 49%, transparent 54%) 72% 43% / 14% 1.2% no-repeat,
    linear-gradient(179.6deg, transparent 45%, rgba(213, 220, 201, 0.25) 49%, transparent 54%) 20% 79% / 20% 1.1% no-repeat,
    linear-gradient(176.8deg, transparent 46%, rgba(222, 226, 207, 0.2) 49%, transparent 53%) 61% 87% / 23% 1.2% no-repeat;
  filter: blur(0.25px);
}

.chalk-haze {
  position: absolute;
  pointer-events: none;
  will-change: transform, opacity;
}

.chalk-haze span {
  position: absolute;
  display: block;
  border-radius: 50%;
  background: radial-gradient(ellipse at center, rgba(226, 228, 211, 0.23), rgba(200, 211, 191, 0.07) 48%, transparent 76%);
}

.chalk-haze--far {
  z-index: 2;
  inset: -16%;
  opacity: 0.16;
  filter: blur(clamp(32px, 4vw, 58px));
  animation: chalk-haze-far 53s ease-in-out -17s infinite alternate;
}

.chalk-haze--far span:nth-child(1) {
  top: 14%;
  left: -2%;
  width: 64%;
  height: 23%;
  transform: rotate(-7deg);
}

.chalk-haze--far span:nth-child(2) {
  top: 48%;
  right: -7%;
  width: 57%;
  height: 29%;
  opacity: 0.7;
  transform: rotate(11deg);
}

.chalk-haze--far span:nth-child(3) {
  bottom: 5%;
  left: 23%;
  width: 49%;
  height: 18%;
  opacity: 0.58;
  transform: rotate(-3deg);
}

.door-scene {
  --door-light-x: 70.5%;
  --door-light-y: 54.5%;
  --beam-angle: 25deg;
  --interaction: 0;
  --light-flicker: 1;
  position: absolute;
  z-index: 4;
  top: 44%;
  left: 50%;
  width: min(46vw, 60rem, 145vh);
  max-width: calc(100vw - 2rem);
  aspect-ratio: 2079 / 756;
  transform: translate(-50%, -50%);
}

.wordmark {
  position: relative;
  z-index: 4;
  width: 100%;
  height: 100%;
  margin: 0;
  line-height: 0;
  user-select: none;
}

.door-logo {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  pointer-events: none;
  user-select: none;
}

.door-beams {
  position: absolute;
  z-index: 1;
  top: var(--door-light-y);
  left: var(--door-light-x);
  width: clamp(18rem, 38vw, 46rem);
  height: clamp(8rem, 20vw, 24rem);
  opacity: calc(0.92 + (var(--interaction) * 0.06));
  pointer-events: none;
  filter: brightness(calc(var(--light-flicker) + (var(--interaction) * 0.05)));
  transform: translate(-1.5%, -50%) rotate(var(--beam-angle));
  transform-origin: 0 50%;
  transition: opacity 850ms ease-out, filter 1100ms ease-in-out;
}

.door-beam,
.door-beam__illuminated-haze {
  position: absolute;
  top: 50%;
  left: 0;
  width: 100%;
  pointer-events: none;
  transform: translateY(-50%);
  transform-origin: 0 50%;
}

.door-beam {
  border-radius: 50%;
  mix-blend-mode: screen;
  -webkit-mask-image: linear-gradient(90deg, #000 0%, rgba(0, 0, 0, 0.91) 17%, rgba(0, 0, 0, 0.48) 60%, transparent 96%);
  mask-image: linear-gradient(90deg, #000 0%, rgba(0, 0, 0, 0.91) 17%, rgba(0, 0, 0, 0.48) 60%, transparent 96%);
}

.door-beam--haze {
  height: 94%;
  opacity: 0.27;
  background:
    radial-gradient(ellipse 18% 24% at 5% 49%, rgba(255, 247, 215, 0.24), rgba(242, 239, 211, 0.075) 54%, transparent 78%),
    radial-gradient(ellipse 38% 33% at 27% 52%, rgba(250, 242, 207, 0.18), rgba(232, 233, 207, 0.058) 58%, transparent 81%),
    radial-gradient(ellipse 54% 43% at 61% 56%, rgba(242, 238, 208, 0.12), rgba(224, 229, 204, 0.04) 59%, transparent 82%),
    radial-gradient(ellipse 38% 31% at 88% 48%, rgba(233, 233, 207, 0.05), transparent 78%);
  filter: blur(clamp(24px, 3vw, 42px));
  animation: door-beam-haze-breathe 10.7s ease-in-out infinite;
}

.door-beam--soft {
  height: 62%;
  opacity: 0.33;
  background:
    radial-gradient(ellipse 17% 27% at 5% 49%, rgba(255, 249, 219, 0.43), rgba(255, 240, 193, 0.12) 54%, transparent 78%),
    radial-gradient(ellipse 39% 37% at 28% 51%, rgba(255, 245, 209, 0.3), rgba(244, 237, 199, 0.085) 58%, transparent 81%),
    radial-gradient(ellipse 51% 47% at 61% 55%, rgba(247, 239, 203, 0.18), rgba(230, 231, 202, 0.045) 61%, transparent 82%),
    radial-gradient(ellipse 34% 34% at 88% 50%, rgba(235, 233, 205, 0.068), transparent 78%);
  filter: blur(clamp(14px, 1.75vw, 25px));
  animation: door-beam-soft-breathe 9.8s ease-in-out -2.6s infinite;
}

.door-beam--core {
  height: 31%;
  opacity: 0.38;
  background:
    radial-gradient(ellipse 15% 30% at 4% 50%, rgba(255, 252, 230, 0.68), rgba(255, 239, 189, 0.19) 55%, transparent 79%),
    radial-gradient(ellipse 38% 40% at 27% 51%, rgba(255, 249, 220, 0.44), rgba(255, 239, 193, 0.11) 59%, transparent 81%),
    radial-gradient(ellipse 50% 49% at 61% 54%, rgba(255, 242, 202, 0.21), rgba(239, 234, 199, 0.045) 61%, transparent 82%),
    radial-gradient(ellipse 31% 38% at 87% 50%, rgba(239, 235, 205, 0.068), transparent 78%);
  filter: blur(clamp(6px, 0.7vw, 11px));
  -webkit-mask-image: linear-gradient(90deg, #000 0%, rgba(0, 0, 0, 0.88) 12%, rgba(0, 0, 0, 0.3) 56%, transparent 89%);
  mask-image: linear-gradient(90deg, #000 0%, rgba(0, 0, 0, 0.88) 12%, rgba(0, 0, 0, 0.3) 56%, transparent 89%);
  animation: door-beam-core-breathe 8.9s ease-in-out -1.3s infinite;
}

.door-beam__illuminated-haze {
  z-index: 2;
  height: 72%;
  opacity: 0.21;
  border-radius: 50%;
  background:
    radial-gradient(ellipse 10% 24% at 9% 43%, rgba(255, 251, 225, 0.62), transparent 72%),
    radial-gradient(ellipse 15% 29% at 27% 56%, rgba(248, 244, 219, 0.39), transparent 73%),
    radial-gradient(ellipse 19% 33% at 49% 46%, rgba(238, 238, 215, 0.27), transparent 75%),
    radial-gradient(ellipse 22% 36% at 72% 61%, rgba(229, 232, 209, 0.17), transparent 76%);
  filter: blur(clamp(9px, 1.2vw, 18px));
  -webkit-mask-image: linear-gradient(90deg, #000 0%, rgba(0, 0, 0, 0.8) 25%, rgba(0, 0, 0, 0.26) 70%, transparent 96%);
  mask-image: linear-gradient(90deg, #000 0%, rgba(0, 0, 0, 0.8) 25%, rgba(0, 0, 0, 0.26) 70%, transparent 96%);
  animation: illuminated-haze-breathe 10.3s ease-in-out -4.1s infinite;
}

.door-beam__cross-fog {
  position: absolute;
  z-index: 3;
  top: 50%;
  left: 31%;
  width: 34%;
  height: 122%;
  border-radius: 50%;
  opacity: 0;
  pointer-events: none;
  background:
    radial-gradient(ellipse 48% 32% at 35% 39%, rgba(242, 241, 222, 0.48), rgba(219, 226, 205, 0.12) 54%, transparent 76%),
    radial-gradient(ellipse 54% 38% at 68% 58%, rgba(235, 237, 217, 0.36), rgba(211, 220, 199, 0.085) 57%, transparent 78%);
  filter: blur(clamp(15px, 1.8vw, 27px));
  mix-blend-mode: screen;
  will-change: transform, opacity;
  animation: cross-beam-chalk-fog 29s ease-in-out -9s infinite;
}

.chalk-haze--mid {
  z-index: 2;
  inset: -125% -82%;
  opacity: 0.12;
  filter: blur(clamp(25px, 3vw, 42px));
  animation: chalk-haze-mid 37s ease-in-out -11s infinite alternate;
}

.chalk-haze--mid span:nth-child(1) {
  top: 19%;
  left: 7%;
  width: 49%;
  height: 21%;
  transform: rotate(7deg);
}

.chalk-haze--mid span:nth-child(2) {
  top: 46%;
  right: 3%;
  width: 58%;
  height: 27%;
  opacity: 0.65;
  transform: rotate(-8deg);
}

.chalk-haze--mid span:nth-child(3) {
  bottom: 7%;
  left: 31%;
  width: 37%;
  height: 19%;
  opacity: 0.55;
}

.door-source {
  position: absolute;
  z-index: 5;
  top: var(--door-light-y);
  left: var(--door-light-x);
  width: clamp(1.5rem, 3.2vw, 3.5rem);
  aspect-ratio: 1;
  opacity: calc(0.78 + (var(--interaction) * 0.12));
  pointer-events: none;
  filter: brightness(calc(var(--light-flicker) + (var(--interaction) * 0.1)));
  transform: translate(-50%, -50%);
  transition: opacity 850ms ease-out, filter 1100ms ease-in-out;
  animation: door-source-breathe 9.4s ease-in-out -2.1s infinite;
}

.door-source span {
  position: absolute;
  display: block;
  border-radius: 50%;
  mix-blend-mode: screen;
}

.door-source__illumination {
  inset: -245%;
  opacity: 0.34;
  background: radial-gradient(circle, rgba(255, 249, 218, 0.33) 0%, rgba(255, 242, 194, 0.12) 24%, rgba(232, 229, 205, 0.035) 49%, transparent 73%);
  filter: blur(clamp(8px, 1vw, 15px));
}

.door-source__halo {
  inset: -78%;
  opacity: 0.76;
  background: radial-gradient(circle, rgba(255, 254, 238, 0.5) 0%, rgba(255, 242, 194, 0.28) 28%, rgba(255, 232, 173, 0.07) 59%, transparent 77%);
  filter: blur(clamp(3px, 0.35vw, 6px));
}

.door-source__core {
  top: 41%;
  left: 41%;
  width: 18%;
  aspect-ratio: 1;
  opacity: 0.88;
  background: #fffdf0;
  filter: blur(0.65px);
  box-shadow: 0 0 0.35rem rgba(255, 244, 206, 0.64);
}

.door-dust {
  position: absolute;
  z-index: 6;
  top: var(--door-light-y);
  left: var(--door-light-x);
  width: clamp(14rem, 34vw, 42rem);
  height: clamp(5rem, 13vw, 15rem);
  opacity: calc(0.66 + (var(--interaction) * 0.08));
  pointer-events: none;
  filter: brightness(calc(var(--light-flicker) + (var(--interaction) * 0.06)));
  transform: translate(-1%, -50%) rotate(var(--beam-angle));
  transform-origin: 0 50%;
  transition: opacity 850ms ease-out, filter 1100ms ease-in-out;
}

.door-dust__particle {
  position: absolute;
  top: var(--particle-y);
  left: var(--particle-x);
  width: var(--particle-size);
  aspect-ratio: 1;
  border-radius: 50%;
  opacity: 0;
  background: rgba(255, 249, 222, 0.88);
  filter: blur(var(--particle-blur));
  box-shadow: 0 0 0.25rem rgba(255, 241, 199, 0.26);
  will-change: transform, opacity;
  animation: chalk-particle-drift var(--particle-duration) linear var(--particle-delay) infinite;
}

.door-dust__particle--fragment {
  border-radius: 44% 56% 62% 38%;
  background: rgba(247, 241, 216, 0.72);
}

.chalk-haze--near {
  z-index: 7;
  inset: -115% -76%;
  opacity: 0.075;
  filter: blur(clamp(18px, 2vw, 29px));
  animation: chalk-haze-near 23s ease-in-out -6s infinite alternate;
}

.chalk-haze--near span:nth-child(1) {
  top: 17%;
  right: 8%;
  width: 43%;
  height: 18%;
  transform: rotate(-6deg);
}

.chalk-haze--near span:nth-child(2) {
  top: 52%;
  left: 2%;
  width: 52%;
  height: 21%;
  opacity: 0.62;
  transform: rotate(9deg);
}

.chalk-haze--near span:nth-child(3) {
  right: 27%;
  bottom: 3%;
  width: 34%;
  height: 16%;
  opacity: 0.46;
}

.blackboard__promise {
  position: absolute;
  z-index: 13;
  bottom: max(clamp(2.2rem, 12.5vh, 8rem), env(safe-area-inset-bottom));
  left: max(clamp(2rem, 10vw, 12rem), env(safe-area-inset-left));
  margin: 0;
  color: rgba(235, 231, 216, 0.8);
  font-family: "Segoe Print", "Bradley Hand", "Chalkboard SE", "Comic Sans MS", cursive;
  font-size: clamp(1rem, 1.9vw, 1.6rem);
  font-weight: 400;
  letter-spacing: 0.04em;
  line-height: 1.25;
  text-shadow:
    0.018em 0.014em rgba(255, 255, 241, 0.18),
    0 0 0.1em rgba(224, 225, 207, 0.12);
  transform: rotate(-0.8deg);
}

@keyframes chalk-haze-far {
  0% { opacity: 0.13; transform: translate3d(-1.8%, 0.4%, 0) scale(1.02); }
  34% { opacity: 0.17; transform: translate3d(0.8%, -0.9%, 0) scale(1.035); }
  71% { opacity: 0.14; transform: translate3d(2.6%, 0.7%, 0) scale(1.015); }
  100% { opacity: 0.16; transform: translate3d(0.3%, -0.4%, 0) scale(1.04); }
}

@keyframes chalk-haze-mid {
  0% { opacity: 0.09; transform: translate3d(-2.2%, 1%, 0) scale(1.01); }
  38% { opacity: 0.13; transform: translate3d(1.1%, -1.2%, 0) scale(1.035); }
  76% { opacity: 0.105; transform: translate3d(3.1%, 0.5%, 0) scale(1.02); }
  100% { opacity: 0.12; transform: translate3d(0.5%, -0.8%, 0) scale(1.045); }
}

@keyframes chalk-haze-near {
  0% { opacity: 0.055; transform: translate3d(-3%, 1.4%, 0) scale(1.02); }
  42% { opacity: 0.082; transform: translate3d(1.4%, -1.5%, 0) scale(1.055); }
  79% { opacity: 0.064; transform: translate3d(3.8%, 0.9%, 0) scale(1.025); }
  100% { opacity: 0.075; transform: translate3d(0.7%, -1%, 0) scale(1.045); }
}

@keyframes door-beam-haze-breathe {
  0%, 100% { opacity: 0.37; transform: translateY(-50%) scaleX(0.99) scaleY(0.97); }
  42% { opacity: 0.47; transform: translateY(-50%) scaleX(1.035) scaleY(1.04); }
  73% { opacity: 0.41; transform: translateY(-50%) scaleX(1.01) scaleY(0.99); }
}

@keyframes door-beam-soft-breathe {
  0%, 100% { opacity: 0.42; transform: translateY(-50%) scaleX(1) scaleY(0.98); }
  46% { opacity: 0.52; transform: translateY(-50%) scaleX(1.045) scaleY(1.045); }
  78% { opacity: 0.46; transform: translateY(-50%) scaleX(1.012) scaleY(1.01); }
}

@keyframes door-beam-core-breathe {
  0%, 100% { opacity: 0.44; transform: translateY(-50%) scaleX(0.99) scaleY(0.98); }
  44% { opacity: 0.54; transform: translateY(-50%) scaleX(1.055) scaleY(1.035); }
  77% { opacity: 0.48; transform: translateY(-50%) scaleX(1.02) scaleY(1); }
}

@keyframes illuminated-haze-breathe {
  0%, 100% { opacity: 0.26; transform: translateY(-50%) translateX(-1%) scale(0.98); }
  51% { opacity: 0.37; transform: translateY(-50%) translateX(2%) scale(1.045); }
  79% { opacity: 0.31; transform: translateY(-50%) translateX(0.5%) scale(1.01); }
}

@keyframes cross-beam-chalk-fog {
  0%, 100% {
    opacity: 0.06;
    transform: translate3d(-8%, -92%, 0) rotate(-13deg) scale(0.9);
  }
  31% {
    opacity: 0.21;
    transform: translate3d(-2%, -67%, 0) rotate(-10deg) scale(1.02);
  }
  53% {
    opacity: 0.38;
    transform: translate3d(4%, -48%, 0) rotate(-7deg) scale(1.09);
  }
  76% {
    opacity: 0.22;
    transform: translate3d(10%, -29%, 0) rotate(-4deg) scale(1.03);
  }
  92% {
    opacity: 0.09;
    transform: translate3d(14%, -10%, 0) rotate(-2deg) scale(0.94);
  }
}

@keyframes door-source-breathe {
  0%, 100% { transform: translate(-50%, -50%) scale(0.98); }
  43% { transform: translate(-50%, -50%) scale(1.045); }
  74% { transform: translate(-50%, -50%) scale(1.01); }
}

@keyframes chalk-particle-drift {
  0% {
    opacity: 0;
    transform: translate3d(-0.25rem, var(--particle-rise), 0) scale(0.62) rotate(0deg);
  }
  14% {
    opacity: var(--particle-opacity);
  }
  58% {
    opacity: var(--particle-opacity-mid);
  }
  82% {
    opacity: var(--particle-opacity-low);
  }
  100% {
    opacity: 0;
    transform: translate3d(var(--particle-travel), var(--particle-fall), 0) scale(1.14) rotate(var(--particle-turn));
  }
}

@media (max-width: 42rem) {
  .door-scene {
    top: 44.5%;
    width: 86vw;
    --beam-angle: 24deg;
  }

  .door-beams {
    width: 58vw;
    height: 34vw;
  }

  .door-dust {
    width: 59vw;
    height: 25vw;
  }

  .chalk-haze--far {
    opacity: 0.12;
  }

  .chalk-haze--near {
    opacity: 0.055;
  }

  .blackboard__promise {
    bottom: max(7.5vh, env(safe-area-inset-bottom));
    left: max(8.5vw, env(safe-area-inset-left));
    font-size: clamp(0.98rem, 4.5vw, 1.16rem);
    letter-spacing: 0.025em;
  }
}

@media (max-height: 32rem) and (min-width: 42.01rem) {
  .door-scene {
    top: 42%;
    width: min(44vw, 125vh);
  }

  .door-beams {
    width: 34vw;
    height: 17vw;
  }

  .blackboard__promise {
    bottom: max(6vh, env(safe-area-inset-bottom));
    font-size: clamp(0.92rem, 1.7vw, 1.25rem);
  }
}

@media (prefers-reduced-motion: reduce) {
  .chalk-haze,
  .door-beam,
  .door-beam__illuminated-haze,
  .door-beam__cross-fog,
  .door-source,
  .door-dust__particle {
    animation: none;
  }

  .chalk-haze--far { opacity: 0.145; transform: none; }
  .chalk-haze--mid { opacity: 0.105; transform: none; }
  .chalk-haze--near { opacity: 0.06; transform: none; }

  .door-beams,
  .door-source,
  .door-dust {
    transition: none;
  }

  .door-beam--haze { opacity: 0.24; transform: translateY(-50%); }
  .door-beam--soft { opacity: 0.3; transform: translateY(-50%); }
  .door-beam--core { opacity: 0.35; transform: translateY(-50%); }
  .door-beam__illuminated-haze { opacity: 0.18; transform: translateY(-50%); }
  .door-beam__cross-fog { opacity: 0.22; transform: translate3d(3%, -50%, 0) rotate(-7deg); }
  .door-source { transform: translate(-50%, -50%); }

  .door-dust__particle {
    opacity: var(--particle-opacity-static);
    transform: none;
  }
}