:root {
  --ink: #073844;
  --teal: #075b6d;
  --green: #00ad4d;
  --sky: #dff5f6;
  --paper: #fffdf7;
  --yellow: #fff238;
  --content: min(1240px, calc(100vw - 64px));
  --display: Futura, "Avenir Next Condensed", "Avenir Next", Avenir, "PingFang TC", "Microsoft JhengHei", sans-serif;
  --sans: "Avenir Next", Avenir, "PingFang TC", "Microsoft JhengHei", sans-serif;
}

html { scroll-padding-top: 88px; }

body {
  min-width: 320px;
  overflow-x: hidden;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  line-height: 1.65;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body.is-loading { overflow: hidden; }
button, a { -webkit-font-smoothing: antialiased; }
a { text-decoration: none; }
button { cursor: pointer; }
.content-width { width: var(--content); margin-inline: auto; }

.skip-link {
  position: fixed;
  z-index: 200;
  top: -60px;
  left: 20px;
  padding: 9px 13px;
  color: white;
  background: var(--ink);
}
.skip-link:focus { top: 20px; }
:focus-visible { outline: 3px solid var(--yellow); outline-offset: 4px; }

/* Loading: a short, quiet fade lets the first scene arrive without competing with it. */
.loading-screen {
  position: fixed;
  z-index: 300;
  inset: 0;
  display: grid;
  place-items: center;
  overflow: hidden;
  color: var(--ink);
  background: var(--sky);
  transition: visibility 1ms linear 420ms, opacity 420ms ease;
}
.loading-screen.is-leaving { visibility: hidden; opacity: 0; }
.loading-background { position: absolute; pointer-events: none; }
.loading-background { inset: 0; width: 100%; height: 100%; object-fit: cover; object-position: center 22%; opacity: .92; }

/* Header */
.site-header {
  position: absolute;
  z-index: 20;
  top: 0;
  left: 50%;
  width: var(--content);
  min-height: 94px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  transform: translateX(-50%);
}
.brand { display: inline-flex; width: fit-content; }
.brand img { width: 184px; height: auto; display: block; }
.site-nav { display: flex; gap: 25px; padding: 10px 20px; border: 1px solid rgb(7 56 68 / 20%); border-radius: 999px; background: rgb(255 255 255 / 53%); backdrop-filter: blur(14px); font-size: 12px; font-weight: 800; letter-spacing: .1em; }
.site-nav a { position: relative; }
.site-nav a::after { position: absolute; right: 0; bottom: -5px; left: 0; height: 1px; content: ""; background: currentColor; transform: scaleX(0); transform-origin: right; transition: transform .22s ease; }
.site-nav a:hover::after, .site-nav a:focus-visible::after { transform: scaleX(1); transform-origin: left; }
.social-links { justify-self: end; display: flex; gap: 9px; }
.social-links a { width: 39px; height: 39px; display: grid; place-items: center; border: 1px solid rgb(7 56 68 / 20%); border-radius: 50%; background: rgb(255 255 255 / 55%); backdrop-filter: blur(12px); transition: transform .22s ease, background .22s ease; }
.social-links a:hover { background: white; transform: translateY(-3px); }
.social-links img { width: 24px; height: 24px; }

/* Hero: a full campaign stage, not a contained card. */
.birthday-hero {
  position: relative;
  isolation: isolate;
  min-height: max(780px, 100svh);
  padding: 150px max(5vw, 54px) 80px;
  display: grid;
  grid-template-columns: minmax(330px, .82fr) minmax(500px, 1.18fr);
  align-items: center;
  gap: clamp(25px, 4vw, 82px);
  overflow: hidden;
  background: var(--sky);
}
.hero-atmosphere, .hero-atmosphere img { position: absolute; pointer-events: none; }
.hero-atmosphere { z-index: -1; inset: 0; }
.hero-poster-background { width: 100%; height: 100%; top: 0; left: 0; object-fit: cover; object-position: center 22%; }
.hero-stars { width: 340px; right: 3%; bottom: -8%; opacity: .68; animation: twinkle 5s ease-in-out infinite alternate; }
.hero-copy { position: relative; z-index: 5; align-self: end; padding-bottom: clamp(22px, 6vh, 72px); animation: rise-in .9s .4s both; }
.hero-kicker, .section-index { margin-bottom: 21px; font-size: 11px; font-weight: 800; letter-spacing: .22em; }
.hero-copy h1 { margin: 0; overflow: visible; color: var(--teal); font-family: var(--display); font-size: clamp(76px, 9.3vw, 168px); font-weight: 800; letter-spacing: -.085em; line-height: .94; }
.hero-copy h1 span { display: block; width: auto; padding-block: .1em; margin-block: -.05em; overflow: visible; white-space: nowrap; opacity: 0; transform: translateY(.12em); }
.hero-copy h1 span:last-child { margin-left: clamp(18px, 4vw, 74px); color: var(--green); }
body:not(.is-loading) .hero-copy h1 span:first-child { animation: reveal-title .68s cubic-bezier(.2,.72,0,1) .1s forwards; }
body:not(.is-loading) .hero-copy h1 span:last-child { animation: reveal-title .86s cubic-bezier(.2,.72,0,1) .42s forwards; }
.hero-tagline { margin-top: clamp(28px, 4.5vh, 54px); font-size: clamp(20px, 2vw, 31px); font-weight: 800; letter-spacing: .04em; line-height: 1.46; }
.hero-period { margin-top: 24px; display: flex; width: min(100%, 520px); align-items: center; color: var(--teal); line-height: 1; }
.poster-year { margin-right: 5px; font-size: 11px; font-weight: 800; letter-spacing: .08em; writing-mode: vertical-rl; }
.poster-date strong { font-family: var(--display); font-size: clamp(44px, 4.55vw, 72px); font-weight: 800; letter-spacing: -.09em; line-height: .72; }
.poster-date > i { margin: 0 8px; font-family: var(--sans); font-size: 19px; font-style: normal; font-weight: 500; }
.poster-date small { align-self: flex-end; margin: 0 8px 2px 3px; font-size: 14px; font-weight: 800; letter-spacing: .04em; }
.poster-date-line { height: 1px; flex: 1; min-width: 36px; background: currentColor; opacity: .65; }
.hero-eligibility-note { margin: 13px 0 0; color: var(--teal); font-size: 13px; font-weight: 800; letter-spacing: .05em; }
.hero-scroll-link { width: fit-content; margin-top: 32px; display: flex; align-items: center; gap: 16px; font-size: 13px; font-weight: 800; letter-spacing: .08em; }
.hero-scroll-link span { width: 37px; height: 37px; display: grid; place-items: center; border: 1px solid currentColor; border-radius: 50%; transition: transform .22s ease, background .22s ease, color .22s ease; }
.hero-scroll-link:hover span { color: white; background: var(--teal); transform: translateY(4px); }
.hero-stage { position: relative; z-index: 3; width: min(100%, 820px); justify-self: end; min-height: 550px; animation: rise-in 1s .18s both; }
.hero-postcard { position: absolute; z-index: 3; right: 0; bottom: 4%; width: min(94%, 760px); padding: 14px; overflow: hidden; border: 1px solid rgb(7 56 68 / 17%); border-radius: 30px; background: rgb(255 255 255 / 82%); box-shadow: 0 34px 82px rgb(0 74 91 / 22%), inset 0 1px 0 white; backdrop-filter: blur(16px); touch-action: pan-y; transform: rotate(1.6deg); }
.postcard-slide { position: absolute; inset: 12px 12px 55px; overflow: hidden; border-radius: 17px; opacity: 0; transform: scale(1.04); transition: opacity .72s ease, transform 4.8s ease; }
.postcard-slide.is-active { position: relative; inset: auto; aspect-ratio: 720 / 491; opacity: 1; transform: scale(1); }
.postcard-slide img { width: 100%; height: 100%; object-fit: cover; }
.postcard-controls { min-height: 47px; padding: 10px 4px 0; display: grid; grid-template-columns: 1fr auto; align-items: center; }
.postcard-dots { display: flex; align-items: center; gap: 10px; }
.postcard-dots button { width: 16px; height: 16px; position: relative; padding: 0; border: 0; border-radius: 50%; background: transparent; }
.postcard-dots button::before { position: absolute; inset: 3px; content: ""; border: 1.5px solid currentColor; border-radius: 50%; transition: background .2s ease, transform .2s ease; }
.postcard-dots button.is-active::before { background: currentColor; transform: scale(1.08); }
.postcard-arrows { display: flex; gap: 7px; }
.postcard-prev, .postcard-next { width: 35px; height: 35px; border: 1px solid rgb(7 56 68 / 28%); border-radius: 50%; color: var(--ink); background: transparent; font-size: 17px; line-height: 1; transition: color .2s ease, background .2s ease, transform .2s ease; }
.postcard-prev:hover, .postcard-next:hover { color: white; background: var(--teal); transform: translateY(-2px); }
.hero-side-note { position: absolute; z-index: 4; right: 34px; bottom: 30px; margin: 0; padding: 11px 15px; border: 1px solid rgb(7 56 68 / 28%); border-radius: 999px; background: rgb(255 255 255 / 65%); backdrop-filter: blur(12px); font-size: 15px; font-weight: 800; letter-spacing: .06em; }

/* BukaFrog mounts a fixed-coordinate SVG rig in each container. The page only
   controls the container's placement; the runtime owns joints and movement. */
.buka-rig { position: absolute; z-index: 6; width: 330px; aspect-ratio: 1 / 1; pointer-events: none; filter: drop-shadow(0 22px 16px rgb(0 66 44 / 17%)); }
.buka-rig .buka-frog-svg { width: 100%; height: 100%; overflow: visible; }
.buka-rig--loading { z-index: 1; right: max(7vw, 38px); bottom: 6%; width: min(210px, 42vw); animation: loading-fade .36s ease both; }
.buka-rig--hero { bottom: -8%; left: -5%; width: min(47%, 365px); }
.buka-rig--intro { left: -130px; bottom: -36px; width: 300px; }
.buka-rig--how-to { right: -3%; bottom: -24%; width: min(410px, 42vw); filter: drop-shadow(0 24px 20px rgb(0 0 0 / 20%)); transform: rotate(9deg); }

/* The scene continues through the introduction and partner list. */
.intro-scene {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  background:
    radial-gradient(95% 82% at -18% 52%, rgb(183 226 235 / 78%) 0%, rgb(218 240 241 / 57%) 48%, transparent 78%),
    radial-gradient(54% 76% at 50% 16%, rgb(226 247 246 / 72%) 0%, transparent 73%),
    linear-gradient(112deg, #e1f3f4 0%, #f3f7f3 52%, #fffdf7 100%);
}
.intro-scene::after { position: absolute; z-index: -1; right: -8vw; bottom: -19vw; width: 54vw; min-width: 700px; aspect-ratio: 1; content: ""; border-radius: 50%; background: radial-gradient(circle at 34% 31%, rgb(255 242 56 / 38%), rgb(218 244 224 / 20%) 54%, transparent 70%); }
/* The source texture has a visible hard edge when cropped; the composed
   gradients above retain its atmosphere without turning into a vertical seam. */
.intro-light { display: none; }
.intro { position: relative; z-index: 1; padding: 78px 0 70px; }
.intro-layout { min-height: 370px; position: relative; display: grid; grid-template-columns: minmax(0, 1.03fr) minmax(430px, .97fr); gap: clamp(34px, 5.5vw, 88px); align-items: center; }
.intro-title-column { min-width: 0; align-self: start; padding-top: 15px; }
.intro-title-column::after { width: min(245px, 40%); height: 1px; margin-top: 38px; display: block; content: ""; background: linear-gradient(90deg, currentColor, transparent); opacity: .3; }
.intro h2, .section-heading h2, .how-to-heading h2 { margin: 0; font-family: var(--display); font-weight: 800; letter-spacing: -.06em; line-height: .96; }
.intro h2 { font-size: clamp(46px, 4.2vw, 70px); }
.intro-message { min-height: 330px; position: relative; isolation: isolate; display: flex; align-items: center; }
.intro-message::before { position: absolute; z-index: -2; inset: 8px -26px 8px -42px; content: ""; border: 1px solid rgb(7 56 68 / 9%); border-radius: 48% 28% 31% 46% / 45% 39% 42% 52%; background: linear-gradient(125deg, rgb(255 255 255 / 36%), rgb(255 253 247 / 82%)); box-shadow: 0 28px 70px rgb(7 56 68 / 8%), inset 0 1px 0 rgb(255 255 255 / 86%); transform: rotate(-1.5deg); }
.intro-message::after { position: absolute; z-index: -1; inset: 34px 18px 22px -82px; content: ""; border: 1px dashed rgb(0 173 77 / 25%); border-radius: 50%; transform: rotate(8deg); }
.intro-copy { position: relative; z-index: 3; max-width: 500px; margin-left: 74px; padding: 48px 34px 48px 102px; font-size: 17px; font-weight: 600; }
.intro-copy p + p { margin-top: 16px; }

.gifts { position: relative; isolation: isolate; overflow: hidden; padding: 118px 0 146px; background: #dff5f6; }
.gifts::before { position: absolute; z-index: -1; inset: 0; content: ""; background-image: url("../images/hero/iridescent.webp"); background-position: 90% 10%; background-size: 680px auto; background-repeat: no-repeat; opacity: .82; mix-blend-mode: screen; }
.gifts-blobs { position: absolute; z-index: -1; top: -230px; right: -570px; width: 1260px; max-width: none; opacity: .76; transform: rotate(16deg); }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 30px; margin-bottom: 48px; }
.section-heading h2 { font-size: clamp(46px, 4.3vw, 70px); }
.how-to-heading h2 { font-size: clamp(53px, 6.2vw, 92px); }
.section-heading > p { margin: 0 6% 11px 0; font-size: 16px; font-weight: 700; line-height: 1.55; }
.brand-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 28px 24px; }
.brand-list > li:nth-child(even) { transform: translateY(62px); }
.brand-card { position: relative; min-height: 306px; width: 100%; padding: 18px; display: grid; grid-template-columns: minmax(165px, 37%) 1fr; gap: 20px; overflow: hidden; border: 2px solid var(--ink); border-radius: 28px; color: var(--ink); background: rgb(255 255 255 / 87%); box-shadow: 0 14px 0 rgb(7 56 68 / 8%); text-align: left; transition: transform .26s ease, box-shadow .26s ease; }
.brand-card::before { position: absolute; top: 0; right: 0; width: 86px; height: 86px; content: ""; background: var(--card-accent); clip-path: polygon(100% 0, 0 0, 100% 100%); opacity: .92; }
.brand-card:hover, .brand-card:focus-visible { box-shadow: 0 22px 0 var(--card-accent); transform: translateY(-7px) rotate(-.4deg); outline: none; }
.brand-list > li:nth-child(even) .brand-card:hover, .brand-list > li:nth-child(even) .brand-card:focus-visible { transform: translateY(-7px) rotate(.4deg); }
.brand-card.is-pending { opacity: .72; filter: saturate(.67); }
.brand-card-media { position: relative; width: 100%; min-width: 0; height: 100%; overflow: hidden; border-radius: 19px; background: var(--card-soft); }
.brand-card-media > img:first-child { width: 100%; height: 100%; object-fit: cover; transition: transform .5s ease; }
.brand-card:hover .brand-card-media > img:first-child { transform: scale(1.06); }
.brand-card-media.is-logo-cover { background: #012c59; }
.brand-card-media.is-logo-cover > img:first-child { object-fit: contain; background: #012c59; }
.brand-card:hover .brand-card-media.is-logo-cover > img:first-child { transform: none; }
.brand-card-logo { position: absolute; right: 0; bottom: 0; left: 0; min-height: 82px; padding: 10px 14px; display: grid; place-items: center; border-radius: 0; background: #fff; box-shadow: 0 -8px 18px rgb(7 56 68 / 10%); }
.brand-card-logo img { width: 100%; height: 62px; object-fit: contain; }
.brand-card-copy { position: relative; z-index: 1; display: flex; flex-direction: column; align-items: flex-start; padding: 4px 6px 0 0; }
.brand-card-copy small { max-width: 82%; font-size: 10px; font-weight: 800; letter-spacing: .06em; opacity: .72; }
.brand-card-copy h3 { margin: 15px 0 9px; font-family: var(--display); font-size: clamp(25px, 2.5vw, 37px); font-weight: 800; letter-spacing: -.045em; line-height: 1.04; }
.brand-card-copy p { max-width: 290px; font-size: 14px; font-weight: 700; line-height: 1.55; }
.brand-card-copy span { margin-top: auto; padding-top: 19px; font-size: 12px; font-weight: 800; letter-spacing: .06em; }

.how-to-scene { position: relative; min-height: 655px; padding: 118px 0 106px; overflow: hidden; color: var(--paper); background: var(--ink); }
.how-to-yushan { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; opacity: .22; filter: saturate(.75); }
.how-to-scene::before { position: absolute; inset: 0; content: ""; background: rgb(7 56 68 / 78%); }
.how-to { position: relative; z-index: 1; }
.how-to-heading { display: grid; grid-template-columns: 1.15fr .85fr; gap: 70px; align-items: end; }
.how-to-heading p { max-width: 410px; margin: 0 0 10px; font-size: 16px; font-weight: 600; }
.how-to ol { margin-top: 66px; display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.how-to li { position: relative; display: flex; gap: 17px; padding-top: 18px; border-top: 1px solid rgb(255 255 255 / 44%); }
.how-to li:not(:last-child)::after { position: absolute; top: 36px; right: -14px; width: 1px; height: 48px; content: ""; background: rgb(255 255 255 / 34%); }
.how-to b { width: 40px; height: 40px; flex: 0 0 40px; display: grid; place-items: center; border: 1px solid currentColor; border-radius: 50%; color: var(--yellow); font-family: var(--display); font-size: 18px; }
.how-to strong, .how-to span { display: block; }
.how-to strong { margin-top: 4px; font-size: 17px; }
.how-to span { margin-top: 6px; font-size: 14px; line-height: 1.55; opacity: .84; }
footer { position: relative; overflow: hidden; color: white; background: #032a35; }
.footer-inner { min-height: 210px; padding: 40px 0 24px; display: grid; grid-template-columns: 170px minmax(0, 1fr); gap: 30px 38px; align-items: center; }
.footer-brand-scene { position: relative; width: 158px; overflow: hidden; }
.footer-logo { width: 158px; height: auto; display: block; }
.footer-inner p { max-width: 520px; margin: 0; font-size: 12px; line-height: 1.65; opacity: .78; }
.footer-inner p + p { margin-top: 8px; }
.footer-inner > .footer-copyright { grid-column: 1 / -1; width: 100%; max-width: none; margin: 0; padding-top: 19px; border-top: 1px solid rgb(255 255 255 / 14%); text-align: center; white-space: normal; }

/* Brand detail: a clear portal over the scene, not a dense document dump. */
.brand-dialog { width: min(1020px, calc(100vw - 30px)); max-height: min(880px, calc(100dvh - 30px)); padding: 0; overflow: auto; border: 0; border-radius: 28px; color: var(--ink); background: var(--paper); }
.brand-dialog::backdrop { background: rgb(0 35 44 / 76%); backdrop-filter: blur(5px); }
.dialog-close { position: sticky; z-index: 6; top: 16px; float: right; width: 45px; height: 45px; margin: 16px 16px -61px 0; display: grid; place-items: center; border: 1px solid rgb(255 255 255 / 45%); border-radius: 50%; color: white; background: var(--ink); font-size: 28px; line-height: 1; }
.detail-head { position: relative; min-height: 280px; padding: 62px clamp(25px, 6vw, 74px) 42px; overflow: hidden; color: var(--detail-ink); background: var(--detail-soft); }
.detail-head::after { position: absolute; top: -67%; right: -11%; width: 480px; height: 480px; content: ""; border-radius: 50%; background: var(--detail-ink); opacity: .08; }
.detail-head small { position: relative; z-index: 1; font-size: 11px; font-weight: 800; letter-spacing: .15em; }
.detail-head h2 { position: relative; z-index: 1; max-width: 780px; margin: 10px 0 8px; font-family: var(--display); font-size: clamp(39px, 5vw, 68px); font-weight: 800; letter-spacing: -.055em; line-height: 1; }
.detail-head strong, .detail-head p { position: relative; z-index: 1; }
.detail-head .detail-tagline { max-width: 700px; margin: 0 0 16px; font-size: clamp(16px, 1.7vw, 22px); font-weight: 700; line-height: 1.35; }
.detail-head strong { display: block; font-size: 18px; }
.detail-head p { max-width: 700px; margin-top: 13px; }
.detail-meta { font-size: 13px; font-weight: 800; }
.detail-body { padding: 42px clamp(25px, 6vw, 74px) 68px; }
.detail-gallery-wrap { position: relative; }
.detail-gallery { display: grid; grid-auto-flow: column; grid-auto-columns: minmax(80%, 1fr); gap: 13px; overflow-x: auto; overscroll-behavior-inline: contain; scroll-behavior: smooth; scroll-snap-type: x mandatory; scrollbar-width: none; }
.detail-gallery::-webkit-scrollbar { display: none; }
.detail-gallery img { width: 100%; aspect-ratio: 850 / 478; object-fit: cover; border-radius: 17px; scroll-snap-align: start; }
.detail-gallery img.is-logo-cover { object-fit: contain; background: #012c59; }
.detail-gallery-controls { position: absolute; right: 14px; bottom: 14px; display: flex; gap: 8px; }
.detail-gallery-controls button { width: 42px; height: 42px; display: grid; place-items: center; border: 1px solid rgb(255 255 255 / 72%); border-radius: 50%; color: white; background: rgb(7 56 68 / 84%); box-shadow: 0 6px 18px rgb(0 0 0 / 18%); font-size: 18px; line-height: 1; transition: transform .2s ease, background .2s ease; }
.detail-gallery-controls button:hover { background: var(--detail-ink); transform: translateY(-2px); }
.detail-content { margin-top: 40px; display: grid; grid-template-columns: minmax(0, 1fr) 278px; gap: 50px; }
.detail-content h3 { margin-bottom: 13px; font-family: var(--display); font-size: 25px; letter-spacing: -.03em; }
.detail-content p + p { margin-top: 15px; }
.detail-list { margin: 14px 0 35px; padding: 0; list-style: none; }
.detail-list li { display: grid; grid-template-columns: 10px minmax(0, 1fr); gap: 12px; align-items: start; }
.detail-list li::before { content: "•"; color: var(--detail-ink); font-size: 18px; font-weight: 800; line-height: 1.25; }
.detail-list li + li { margin-top: 10px; }
.detail-step-copy, .detail-step-note { display: block; }
.detail-step-note { margin-top: 5px; color: var(--detail-ink); font-size: .82em; line-height: 1.55; opacity: .76; }
.detail-content-main { min-width: 0; }
.detail-section { margin: 0; padding: 0; }
.detail-section > h3 { margin-left: 0; }
.detail-section > .detail-list { margin-left: 0; }
.detail-offer { align-self: start; padding: 23px; border-radius: 17px; background: var(--detail-soft); }
.detail-offer dl { margin: 19px 0; font-size: 14px; }
.detail-offer dt { margin-top: 13px; font-weight: 800; }
.detail-offer dd { margin: 3px 0 0; }
.detail-offer a { display: flex; justify-content: space-between; margin-top: 10px; padding: 13px; border-radius: 10px; color: white; background: var(--detail-ink); font-size: 13px; font-weight: 800; }
.detail-offer a.secondary { border: 1px solid currentColor; color: var(--detail-ink); background: transparent; }
.detail-qr { width: min(182px, 100%); margin: 20px auto; }
.detail-rules { margin-top: 43px; padding-top: 29px; border-top: 1px solid rgb(7 56 68 / 16%); }
.detail-rules .detail-list { margin-bottom: 0; font-size: 13px; line-height: 1.58; }
.pending-note { margin-top: 22px; padding: 12px; border: 1px dashed currentColor; border-radius: 10px; font-size: 13px; }

@keyframes loading-fade { from { opacity: 0; } to { opacity: 1; } }
@keyframes rise-in { from { opacity: 0; transform: translateY(32px); } to { opacity: 1; transform: translateY(0); } }
@keyframes drift-left { from { transform: translate3d(-1.5%, -1%, 0) rotate(-2deg); } to { transform: translate3d(2%, 1.5%, 0) rotate(1deg); } }
@keyframes drift-right { from { transform: translate3d(2%, -2%, 0) rotate(2deg); } to { transform: translate3d(-2%, 1%, 0) rotate(-1deg); } }
@keyframes drift-bottom { from { transform: translate3d(0, 2%, 0) rotate(-2deg); } to { transform: translate3d(-3%, -1%, 0) rotate(2deg); } }
@keyframes twinkle { from { opacity: .42; transform: scale(.96); } to { opacity: .75; transform: scale(1.03); } }
@keyframes reveal-title { to { opacity: 1; transform: translateY(0); } }
@keyframes mobile-title-in { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

@media (max-width: 920px) {
  .site-header { min-height: 80px; }
  .site-nav { display: none; }
  /* With the centre navigation hidden, retain the third grid column so the
     social buttons stay anchored to the right rather than sliding into centre. */
  .social-links { grid-column: 3; }
  .birthday-hero { min-height: 820px; grid-template-columns: 1fr; padding: 120px max(6vw, 25px) 70px; gap: 0; }
  .hero-copy { align-self: start; padding: 0; }
  .hero-stage { width: min(100%, 690px); min-height: 460px; justify-self: center; margin-top: -18px; }
  .hero-side-note { display: none; }
  .intro { padding: 86px 0 90px; }
  .intro-layout { min-height: 0; grid-template-columns: 1fr; gap: 34px; }
  .intro-message { width: min(690px, 100%); min-height: 310px; margin-left: auto; }
  .intro-copy { max-width: 540px; margin-left: 150px; padding-left: 92px; }
  .buka-rig--intro { left: -12px; bottom: -30px; width: min(290px, 38vw); }
  .brand-list { grid-template-columns: 1fr; gap: 22px; }
  .brand-list > li:nth-child(even) { transform: none; }
  .brand-card { min-height: 286px; grid-template-columns: minmax(220px, 34%) 1fr; }
  .brand-list { gap: 20px; }
  .how-to-heading { gap: 35px; }
  .footer-inner { grid-template-columns: 158px 1fr; }
}

@media (max-width: 640px) {
  :root { --content: min(100% - 36px, 1240px); }
  .loading-background { object-position: center 18%; }
  .buka-rig--loading { right: 4%; bottom: 7%; width: min(190px, 48vw); }
  .site-header { width: var(--content); min-height: 70px; }
  .brand img { width: 154px; }
  .social-links { gap: 6px; }
  .social-links a { width: 34px; height: 34px; }
  .social-links img { width: 21px; height: 21px; }
  .birthday-hero { min-height: 770px; padding: 101px 18px 44px; }
  .hero-poster-background { object-position: center 18%; }
  .hero-stars { width: 190px; right: -14%; bottom: 3%; }
  .hero-copy { width: var(--content); margin: 0 auto; }
  .hero-kicker, .section-index { font-size: 10px; }
  .hero-copy h1 { font-size: clamp(45px, 13.4vw, 66px); letter-spacing: -.07em; line-height: .98; }
  .hero-copy h1 span:last-child { margin-left: clamp(8px, 3vw, 16px); }
  .hero-tagline { margin-top: 28px; font-size: 19px; }
  .hero-period { margin-top: 21px; width: 100%; }
  .hero-eligibility-note { margin-top: 11px; font-size: 12px; }
  .poster-year { margin-right: 3px; font-size: 10px; }
  .poster-date strong { font-size: clamp(45px, 14vw, 61px); }
  .poster-date > i { margin: 0 5px; font-size: 15px; }
  .poster-date small { margin-right: 5px; font-size: 12px; }
  .hero-scroll-link { margin-top: 23px; }
  .hero-stage { width: 100%; min-height: 362px; margin-top: 8px; }
  .hero-postcard { right: -3%; bottom: 0; width: 92%; padding: 8px; border-radius: 17px; }
  .postcard-slide { inset: 8px 8px 45px; border-radius: 11px; }
  .postcard-controls { min-height: 39px; padding-top: 7px; }
  .postcard-prev, .postcard-next { width: 32px; height: 32px; font-size: 14px; }
  .buka-rig--hero { bottom: -8%; left: -13%; width: 52%; }
  .intro-light { top: -13%; left: -55%; width: 145%; }
  .intro-scene { display: block; }
  .intro { padding: 68px 0 72px; }
  .buka-rig--intro {
    left: auto;
    right: -8px;
    top: -28px;
    bottom: auto;
    width: min(230px, 56vw);
  }
  .intro-layout, .how-to-heading { grid-template-columns: 1fr; gap: 25px; }
  .intro h2 { font-size: clamp(40px, 11.5vw, 52px); }
  .intro-title-column::after { margin-top: 27px; }
  .intro-message { min-height: 390px; }
  .intro-message::before { inset: 34px 0 0 10px; border-radius: 34% 18px 18px 18px; }
  .intro-message::after { inset: 58px 16px 28px 0; }
  .intro-copy { max-width: 100%; margin: 112px 0 0; padding: 116px 24px 30px; font-size: 16px; }
  .gifts { padding: 86px 0 102px; }
  .gifts::before { background-size: 430px auto; background-position: 150% 0; }
  .gifts-blobs { top: -90px; right: -525px; opacity: .61; }
  .section-heading { align-items: start; flex-direction: column; gap: 15px; margin-bottom: 34px; }
  .section-heading h2 { font-size: clamp(40px, 11.5vw, 52px); }
  .how-to-heading h2 { font-size: clamp(52px, 17vw, 74px); }
  .section-heading > p { margin: 0; font-size: 14px; }
  .brand-list { grid-template-columns: 1fr; gap: 17px; }
  .brand-list > li:nth-child(even) { transform: none; }
  .brand-card { min-height: 210px; padding: 12px; grid-template-columns: 36% 1fr; gap: 13px; border-radius: 20px; }
  .brand-card::before { width: 64px; height: 64px; }
  .brand-card-media { border-radius: 13px; }
  .brand-card-logo { right: 0; bottom: 0; left: 0; min-height: 58px; padding: 7px 9px; border-radius: 0; }
  .brand-card-logo img { height: 44px; }
  .brand-card-copy { padding-top: 3px; }
  .brand-card-copy small { font-size: 9px; }
  .brand-card-copy h3 { margin: 8px 0 7px; font-size: clamp(24px, 7.2vw, 34px); }
  .brand-card-copy p { font-size: 13px; line-height: 1.45; }
  .brand-card-copy span { padding-top: 10px; font-size: 11px; }
  .how-to-scene { min-height: auto; padding: 86px 0 126px; }
  .how-to-heading p { font-size: 15px; }
  .how-to ol { margin-top: 42px; grid-template-columns: 1fr; gap: 22px; }
  .how-to li { padding-top: 14px; }
  .how-to li:not(:last-child)::after { display: none; }
  .buka-rig--how-to { right: -26%; bottom: -11%; width: 75%; }
  .footer-inner { min-height: 0; padding: 38px 0; grid-template-columns: 1fr; gap: 20px; }
  .footer-brand-scene, .footer-logo { width: 146px; }
  .footer-inner > .footer-copyright { grid-column: auto; }
  .brand-dialog { width: 100%; max-height: 100dvh; margin: auto 0 0; border-radius: 26px 26px 0 0; }
  .detail-head { min-height: 247px; padding: 61px 25px 35px; }
  .detail-body { padding: 28px 25px 56px; }
  .detail-content { grid-template-columns: 1fr; gap: 28px; margin-top: 29px; }
  .detail-gallery { grid-auto-columns: 92%; }
  .detail-gallery-controls { right: 10px; bottom: 10px; }
  .detail-gallery-controls button { width: 38px; height: 38px; }
  .detail-offer { order: -1; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  .hero-copy h1 span { opacity: 1; transform: none; }
}