/* VibeArena opening: the mark assembles, the arena "builds", an iris opens.
 *
 * Built from the logo itself: the crimson V drops in, the silver A rises to
 * meet it, they lock with a flash, the star glints, and a one-line terminal
 * under the mark types while the page really loads (js/page-transition.js
 * flips it to "ready"). The reveal is an iris that opens from the mark's
 * centre while the mark swells and fades, as if you fly through it.
 *
 * States set by the script:
 *   is-outgoing  login → Arena: the iris closes on the old page, mark builds
 *   is-covered   page loading: mark built, terminal typing
 *   is-incoming  page ready: iris opens onto the page
 */
@property --va-iris {
  syntax: "<length>";
  inherits: true;
  initial-value: 0px;
}

:root {
  --va-wine-0: #160008;
  --va-wine-1: #2a000e;
  --va-wine-2: #520013;
  --va-crimson: #ff0a5a;
  --va-crimson-soft: #ff8fb2;
  --va-silver: #f2edf0;
  --va-mark-size: clamp(9.5rem, 24vw, 15rem);
}

.va-page-transition {
  position: fixed;
  inset: 0;
  z-index: 2147483647;
  overflow: hidden;
  visibility: hidden;
  pointer-events: none;
  isolation: isolate;
  font-family: "JetBrains Mono", ui-monospace, Menlo, Consolas, monospace;
  --va-iris: 0px;
}

.va-page-transition *,
.va-page-transition *::before,
.va-page-transition *::after { box-sizing: border-box; }

.va-page-transition.is-outgoing,
.va-page-transition.is-covered,
.va-page-transition.is-incoming {
  visibility: visible;
  pointer-events: auto;
}

/* The curtain: wine, a faint code grid and a glow behind the mark. It is cut
   by a circular hole of radius --va-iris, which is how the iris opens. */
.va-transition-curtain {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 50% 46%, rgb(255 10 90 / .30), transparent 34%),
    radial-gradient(circle at 50% 46%, rgb(255 10 90 / .10), transparent 60%),
    repeating-linear-gradient(90deg, rgb(255 255 255 / .025) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(0deg, rgb(255 255 255 / .025) 0 1px, transparent 1px 64px),
    linear-gradient(150deg, var(--va-wine-2), var(--va-wine-1) 45%, var(--va-wine-0));
  -webkit-mask: radial-gradient(circle at 50% 46%, transparent var(--va-iris), #000 calc(var(--va-iris) + 1px));
          mask: radial-gradient(circle at 50% 46%, transparent var(--va-iris), #000 calc(var(--va-iris) + 1px));
}

/* A crimson ring rides the edge of the iris as it opens. */
.va-transition-ring {
  position: absolute;
  left: 50%;
  top: 46%;
  width: calc(var(--va-iris) * 2);     /* the hole's diameter */
  aspect-ratio: 1;
  border-radius: 50%;
  transform: translate(-50%, -50%);
  border: 2px solid rgb(255 10 90 / .9);
  box-shadow: 0 0 22px rgb(255 10 90 / .7), inset 0 0 22px rgb(255 10 90 / .5);
  opacity: 0;
}

.va-transition-stage {
  position: absolute;
  left: 50%;
  top: 46%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.4rem;
  transform: translate(-50%, -50%);
}

.va-transition-mark {
  position: relative;
  width: var(--va-mark-size);
  aspect-ratio: 1;
}

.va-transition-mark img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  opacity: 0;
  filter: drop-shadow(0 18px 26px rgb(0 0 0 / .55));
  will-change: transform, opacity, filter;
}

/* The V is the left of the logo, the A the right; the cut follows the A's
   left leg so each piece carries its own letter. */
.va-transition-v { clip-path: polygon(0 0, 63% 0, 47% 100%, 0 100%); }
.va-transition-a { clip-path: polygon(63% 0, 100% 0, 100% 100%, 47% 100%); }

/* The flash where the two letters lock. */
.va-transition-flash {
  position: absolute;
  left: 55%;
  top: 50%;
  width: 4px;
  height: 92%;
  transform: translate(-50%, -50%) rotate(16deg) scaleY(0);
  background: linear-gradient(to bottom, transparent, #fff 30%, var(--va-crimson) 60%, transparent);
  box-shadow: 0 0 14px var(--va-crimson), 0 0 40px rgb(255 10 90 / .8);
  opacity: 0;
}

/* The star in the logo's top right gets a glint of its own: a four point
   sparkle sitting exactly on it. */
.va-transition-glint {
  position: absolute;
  left: 80%;
  top: 27%;
  width: 34%;
  aspect-ratio: 1;
  transform: translate(-50%, -50%) scale(0) rotate(-30deg);
  background:
    radial-gradient(circle, #fff 0 5%, rgb(255 255 255 / .55) 9%, transparent 22%),
    linear-gradient(90deg, transparent 47%, rgb(255 255 255 / .95) 50%, transparent 53%),
    linear-gradient(0deg, transparent 47%, rgb(255 255 255 / .95) 50%, transparent 53%);
  -webkit-mask: radial-gradient(circle, #000 0 18%, transparent 50%);
          mask: radial-gradient(circle, #000 0 18%, transparent 50%);
  opacity: 0;
}

/* The one-line terminal under the mark. */
.va-transition-term {
  min-width: 16ch;
  color: var(--va-crimson-soft);
  font-size: clamp(.95rem, 1.5vw, 1.15rem);
  letter-spacing: .02em;
  white-space: nowrap;
  opacity: 0;
}
.va-transition-term .va-term-text {
  display: inline-block;
  overflow: hidden;
  vertical-align: bottom;
  width: 0;
}
.va-transition-term .va-term-caret {
  display: inline-block;
  width: .55em;
  height: 1.05em;
  margin-left: 2px;
  vertical-align: -.15em;
  background: var(--va-crimson);
  animation: va-caret 900ms steps(1) infinite;
}
.va-transition-term.is-ready { color: #dfff00; }
.va-transition-term.is-ready .va-term-caret { display: none; }

/* ── assembling: shared by is-outgoing (after the iris closes) and
      is-covered (a fresh page) ──────────────────────────────────── */
.va-page-transition.is-covered .va-transition-v,
.va-page-transition.is-outgoing .va-transition-v {
  animation: va-v-in 620ms cubic-bezier(.2, .9, .25, 1.12) var(--va-build-at, 60ms) both;
}
.va-page-transition.is-covered .va-transition-a,
.va-page-transition.is-outgoing .va-transition-a {
  animation: va-a-in 620ms cubic-bezier(.2, .9, .25, 1.12) calc(var(--va-build-at, 60ms) + 140ms) both;
}
.va-page-transition.is-covered .va-transition-flash,
.va-page-transition.is-outgoing .va-transition-flash {
  animation: va-flash 520ms ease-out calc(var(--va-build-at, 60ms) + 560ms) both;
}
.va-page-transition.is-covered .va-transition-glint,
.va-page-transition.is-outgoing .va-transition-glint {
  animation: va-glint 700ms ease-out calc(var(--va-build-at, 60ms) + 680ms) both;
}
.va-page-transition.is-covered .va-transition-term,
.va-page-transition.is-outgoing .va-transition-term {
  animation: va-fade-in 260ms ease calc(var(--va-build-at, 60ms) + 620ms) both;
}
.va-page-transition.is-covered .va-term-text,
.va-page-transition.is-outgoing .va-term-text {
  animation: va-type 900ms steps(20, end) calc(var(--va-build-at, 60ms) + 700ms) both;
}
/* While waiting on the page, the mark breathes. */
.va-page-transition.is-covered .va-transition-mark {
  animation: va-breathe 2.2s ease-in-out 1.4s infinite;
}

/* login → Arena: the iris first closes over the login page. */
.va-page-transition.is-outgoing { --va-build-at: 420ms; }
.va-page-transition.is-outgoing .va-transition-curtain {
  animation: va-iris-close 560ms cubic-bezier(.65, 0, .35, 1) both;
}

/* Picking up where the last page left off (after login, or a second visit
   in the same session): the mark is already built, nothing replays. */
.va-page-transition.is-continued .va-transition-v,
.va-page-transition.is-continued .va-transition-a,
.va-page-transition.is-continued .va-transition-term { animation: none; opacity: 1; }
.va-page-transition.is-continued .va-transition-flash,
.va-page-transition.is-continued .va-transition-glint { animation: none; opacity: 0; }
.va-page-transition.is-continued .va-term-text { animation: none; width: 20ch; }

/* ── reveal: the iris opens and the mark flies at you ─────────── */
.va-page-transition.is-incoming .va-transition-v,
.va-page-transition.is-incoming .va-transition-a { opacity: 1; }
.va-page-transition.is-incoming .va-transition-term { opacity: 1; }
.va-page-transition.is-incoming .va-term-text { width: 20ch; }
.va-page-transition.is-incoming .va-transition-stage {
  animation: va-fly-through 820ms cubic-bezier(.55, 0, .3, 1) both;
}
.va-page-transition.is-incoming .va-transition-curtain {
  animation: va-iris-open 880ms cubic-bezier(.55, 0, .35, 1) 100ms both;
}
.va-page-transition.is-incoming .va-transition-ring {
  animation: va-ring 880ms cubic-bezier(.55, 0, .35, 1) 100ms both;
}

@keyframes va-v-in {
  0%   { opacity: 0; transform: translate(-38%, -34%) rotate(-8deg) scale(.92); filter: blur(8px) drop-shadow(0 18px 26px rgb(0 0 0 / .55)); }
  70%  { opacity: 1; filter: blur(0) drop-shadow(0 18px 26px rgb(0 0 0 / .55)); }
  100% { opacity: 1; transform: none; filter: drop-shadow(0 18px 26px rgb(0 0 0 / .55)); }
}
@keyframes va-a-in {
  0%   { opacity: 0; transform: translate(34%, 36%) rotate(7deg) scale(.92); filter: blur(8px) drop-shadow(0 18px 26px rgb(0 0 0 / .55)); }
  70%  { opacity: 1; filter: blur(0) drop-shadow(0 18px 26px rgb(0 0 0 / .55)); }
  100% { opacity: 1; transform: none; filter: drop-shadow(0 18px 26px rgb(0 0 0 / .55)); }
}
@keyframes va-flash {
  0%   { opacity: 0; transform: translate(-50%, -50%) rotate(16deg) scaleY(0); }
  35%  { opacity: 1; transform: translate(-50%, -50%) rotate(16deg) scaleY(1); }
  100% { opacity: 0; transform: translate(-50%, -50%) rotate(16deg) scaleY(1.1); }
}
@keyframes va-glint {
  0%   { opacity: 0; transform: translate(-50%, -50%) scale(0) rotate(-30deg); }
  40%  { opacity: 1; transform: translate(-50%, -50%) scale(1.1) rotate(0deg); }
  100% { opacity: 0; transform: translate(-50%, -50%) scale(.5) rotate(25deg); }
}
@keyframes va-type { from { width: 0; } to { width: 20ch; } }
@keyframes va-caret { 50% { opacity: 0; } }
@keyframes va-fade-in { from { opacity: 0; } to { opacity: 1; } }
@keyframes va-breathe {
  0%, 100% { transform: scale(1); filter: brightness(1); }
  50%      { transform: scale(1.03); filter: brightness(1.12); }
}
@keyframes va-iris-close { from { --va-iris: 75vmax; } to { --va-iris: 0px; } }
@keyframes va-iris-open  { from { --va-iris: 0px; }   to { --va-iris: 75vmax; } }
@keyframes va-ring {
  0%   { opacity: 0; --va-iris: 0px; }
  15%  { opacity: 1; }
  100% { opacity: 0; --va-iris: 75vmax; }
}
@keyframes va-fly-through {
  0%   { opacity: 1; transform: translate(-50%, -50%) scale(1); }
  100% { opacity: 0; transform: translate(-50%, -50%) scale(2.4); filter: blur(6px); }
}

@media (max-width: 650px) {
  :root { --va-mark-size: clamp(8.5rem, 46vw, 12rem); }
}

/* Reduced motion: no flying parts, just a quick fade in and out. */
@media (prefers-reduced-motion: reduce) {
  .va-page-transition .va-transition-flash,
  .va-page-transition .va-transition-glint,
  .va-page-transition .va-transition-ring { display: none; }
  .va-page-transition .va-transition-mark img,
  .va-page-transition .va-transition-term,
  .va-page-transition .va-term-text,
  .va-page-transition .va-transition-mark,
  .va-page-transition .va-transition-stage,
  .va-page-transition .va-transition-curtain { animation: none !important; }
  .va-page-transition .va-transition-mark img,
  .va-page-transition .va-transition-term { opacity: 1; }
  .va-page-transition .va-term-text { width: 20ch; }
  .va-page-transition.is-outgoing { animation: va-fade-in 120ms ease both; }
  .va-page-transition.is-incoming { animation: va-fade-out 160ms ease both; }
}
@keyframes va-fade-out { from { opacity: 1; } to { opacity: 0; } }