/* 3D world viewer */
html, body.world { height: 100%; overflow: hidden; overscroll-behavior: none; }
/* light, airy glass UI over the 3D scene */
body.world { --glass: rgba(255, 255, 255, 0.86); --glass-line: rgba(28, 25, 23, 0.08); color: var(--text); }
body.world { touch-action: none; -webkit-user-select: none; user-select: none; -webkit-touch-callout: none; background: #fff; }
body.world::before { display: none; }
#stage { position: fixed; inset: 0; }
#stage canvas { display: block; width: 100%; height: 100%; touch-action: none; }

.loader { position: fixed; inset: 0; display: grid; place-items: center; z-index: 30; background: #fff; transition: opacity 0.5s; }
.loader .spin { width: 44px; height: 44px; border-radius: 50%; border: 3px solid var(--line); border-top-color: var(--accent); animation: spin 0.9s linear infinite; margin: 0 auto 14px; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------- HUD ---------- */
.hud { position: fixed; inset: 0; pointer-events: none; z-index: 10; }
.hud > * { pointer-events: auto; }
.hud-top { position: absolute; top: max(10px, env(safe-area-inset-top)); left: 10px; right: 10px; display: flex; gap: 8px; align-items: center; pointer-events: none; }
.hud-top > * { pointer-events: auto; }
.hud-title { background: var(--glass); color: var(--text); box-shadow: var(--shadow-sm); backdrop-filter: blur(10px); border: 1px solid var(--glass-line); padding: 8px 14px; border-radius: 14px; font-weight: 700; font-size: 0.9rem; max-width: 55vw; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.hud-title small { display: block; font-weight: 600; opacity: 0.7; font-size: 0.72rem; }
.hud-btn { width: 44px; height: 44px; border-radius: 14px; border: 1px solid var(--glass-line); background: var(--glass); box-shadow: var(--shadow-sm); backdrop-filter: blur(10px); color: var(--text); font-size: 1.15rem; display: grid; place-items: center; cursor: pointer; flex: none; }
.hud-btn.on { background: var(--accent); border-color: transparent; color: #fff; }
.hud-bottom { position: absolute; bottom: max(14px, env(safe-area-inset-bottom)); right: 12px; display: flex; flex-direction: column; gap: 8px; align-items: flex-end; }
.room-nav { display: flex; gap: 8px; }
.room-nav button { font: inherit; font-weight: 700; font-size: 0.85rem; color: var(--text); border: 1px solid var(--glass-line); background: var(--glass); box-shadow: var(--shadow-sm); backdrop-filter: blur(10px); padding: 11px 14px; border-radius: 14px; cursor: pointer; min-height: 44px; }
.room-nav button.primary { background: var(--accent); border-color: transparent; color: #fff; }
.room-nav button[disabled] { opacity: 0.35; }

.joystick { position: absolute; left: max(18px, env(safe-area-inset-left)); bottom: max(22px, env(safe-area-inset-bottom)); width: 128px; height: 128px; border-radius: 50%; background: rgba(255, 255, 255, 0.35); border: 1.5px solid rgba(255, 255, 255, 0.7); box-shadow: 0 4px 18px rgba(0, 0, 0, 0.12); backdrop-filter: blur(6px); touch-action: none; }
.joystick .knob { position: absolute; left: 50%; top: 50%; width: 54px; height: 54px; margin: -27px 0 0 -27px; border-radius: 50%; background: #fff; box-shadow: 0 4px 16px rgba(0, 0, 0, 0.22); transition: transform 0.08s; }
.joystick::after { content: ''; position: absolute; inset: 0; border-radius: 50%; box-shadow: 0 0 0 0 var(--accent); }
@media (hover: hover) and (pointer: fine) { .joystick { display: none; } }

.room-toast { position: absolute; top: 72px; left: 50%; transform: translate(-50%, -10px); background: var(--glass); color: var(--text); box-shadow: var(--shadow-sm); backdrop-filter: blur(10px); padding: 10px 18px; border-radius: 99px; font-weight: 800; opacity: 0; transition: 0.4s; pointer-events: none; white-space: nowrap; border: 1px solid var(--glass-line); }
.room-toast.show { opacity: 1; transform: translate(-50%, 0); }
.help-tip { position: absolute; left: 50%; bottom: 170px; transform: translateX(-50%); background: var(--glass); color: var(--text); box-shadow: var(--shadow); backdrop-filter: blur(10px); padding: 12px 16px; border-radius: 16px; font-size: 0.88rem; text-align: center; max-width: min(92vw, 380px); border: 1px solid var(--glass-line); transition: opacity 0.5s; }
@media (hover: hover) and (pointer: fine) { .help-tip { bottom: 90px; } }
.preview-bar { position: fixed; top: 0; left: 0; right: 0; z-index: 11; background: #fbf0dc; color: #6b4a12; border-bottom: 1px solid #f0d9b0; display: flex; gap: 6px; justify-content: center; align-items: center; flex-wrap: wrap; font-weight: 700; font-size: 0.82rem; text-align: center; padding: 6px 10px; }
.preview-bar a { color: inherit; }
body.has-preview .hud-top { top: 40px; }

/* ---------- overlays ---------- */
.ov { position: fixed; inset: 0; z-index: 40; background: rgba(255, 255, 255, 0.82); backdrop-filter: blur(12px); display: flex; align-items: center; justify-content: center; padding: 16px; animation: fadeIn 0.25s; }
.ov-close { position: absolute; top: max(12px, env(safe-area-inset-top)); right: 12px; z-index: 2; }
.photo-view { width: 100%; max-width: 900px; display: flex; flex-direction: column; gap: 14px; align-items: center; }
.photo-view .img { width: 100%; height: min(64vh, 640px); background-size: contain; background-position: center; background-repeat: no-repeat; border-radius: 12px; animation: zoomIn 0.35s ease; filter: drop-shadow(0 18px 40px rgba(0, 0, 0, 0.18)); }
@keyframes zoomIn { from { transform: scale(0.85); opacity: 0; } }
.photo-view .cap { font-family: var(--serif); font-size: 1.1rem; text-align: center; max-width: 640px; line-height: 1.6; white-space: pre-wrap; }
.photo-view .nav-row { display: flex; gap: 10px; align-items: center; }
.letter-paper { width: 100%; max-width: 620px; max-height: 84vh; overflow: auto; background: #fbf5e8; color: #3a2a1a; border-radius: 6px; padding: 34px 28px; font-family: var(--serif); font-size: 1.08rem; line-height: 1.85; box-shadow: 0 30px 80px rgba(28, 25, 23, 0.18); border: 1px solid #efe4cf; position: relative; animation: unfold 0.7s cubic-bezier(.2, .9, .3, 1.2); transform-origin: top center; -webkit-user-select: text; user-select: text; }
.letter-paper::before { content: ''; position: absolute; inset: 0; background: repeating-linear-gradient(transparent 0 31px, rgba(160, 120, 80, 0.13) 31px 32px); pointer-events: none; border-radius: 6px; }
.letter-paper h2 { font-family: var(--serif); font-style: italic; color: var(--accent); }
.letter-paper .body { white-space: pre-wrap; }
.letter-paper .sign { text-align: right; margin-top: 18px; font-style: italic; }
@keyframes unfold { from { transform: perspective(900px) rotateX(-75deg); opacity: 0; } }
.caret::after { content: '|'; animation: pulse 0.8s infinite; }
.surprise-box { width: 100%; max-width: 440px; text-align: center; background: #fff; color: var(--text); border: 1px solid var(--line); border-radius: 24px; padding: 26px 22px; box-shadow: var(--shadow); }
.surprise-box .msg { font-family: var(--serif); font-size: 1.25rem; line-height: 1.7; white-space: pre-wrap; animation: zoomIn 0.5s ease; }
.sheet { position: fixed; left: 50%; bottom: 0; transform: translate(-50%, 110%); width: min(520px, 100%); background: #fff; color: var(--text); border: 1px solid var(--line); border-radius: 24px 24px 0 0; padding: 20px 18px max(20px, env(safe-area-inset-bottom)); z-index: 35; transition: transform 0.45s cubic-bezier(.2, .9, .3, 1); box-shadow: var(--shadow); }
.sheet.show { transform: translate(-50%, 0); }
.menu-list { display: grid; gap: 8px; }
.menu-list a, .menu-list button { display: flex; gap: 12px; align-items: center; font: inherit; font-weight: 700; color: var(--text); text-decoration: none; padding: 14px; background: #faf8f5; border: 1px solid var(--line); border-radius: 14px; cursor: pointer; text-align: left; }

/* ---------- privacy mode ---------- */
.watermark { position: fixed; inset: 0; z-index: 20; pointer-events: none; opacity: 0.16; background-repeat: repeat; }
.shield { position: fixed; inset: 0; z-index: 100; background: #fff; display: none; place-items: center; text-align: center; padding: 20px; }
body.shielded .shield { display: grid; }
body.shielded #stage, body.shielded .ov { filter: blur(30px); }

/* ---------- intros ---------- */
.intro { position: fixed; inset: 0; z-index: 50; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 22px; padding: 24px 16px; text-align: center; background: radial-gradient(60% 50% at 50% 38%, color-mix(in srgb, var(--a) 18%, transparent), transparent 70%), #fff; color: var(--text); transition: opacity 0.8s; overflow: hidden; }
.intro.gone { opacity: 0; pointer-events: none; }
.intro-text { position: relative; z-index: 2; transition: opacity 0.4s, transform 0.4s; max-width: 560px; }
.intro.opening .intro-text { opacity: 0; transform: translateY(20px); }
.intro-text .for { font-size: 1.05rem; color: var(--muted); margin-bottom: 8px; }
.intro-text h1 { font-size: clamp(1.7rem, 6vw, 2.6rem); margin-bottom: 8px; }
.intro-text .from { color: var(--muted); margin-bottom: 22px; }
.intro-open { background: linear-gradient(120deg, var(--a), color-mix(in srgb, var(--a) 50%, var(--g))); }
.intro-stage { position: relative; width: 240px; height: 240px; display: grid; place-items: center; }
.iv { position: relative; width: 100%; height: 100%; }

/* heart: two halves swing open */
.iv.heart .half { position: absolute; inset: 20px; filter: drop-shadow(0 0 24px var(--a)); transition: transform 1.2s cubic-bezier(.6, 0, .2, 1); animation: beat 1.2s ease-in-out infinite; }
.iv.heart svg { width: 100%; height: 100%; fill: var(--a); }
.iv.heart .half.l { clip-path: inset(-60px 50% -60px -60px); transform-origin: 50% 100%; }
.iv.heart .half.r { clip-path: inset(-60px -60px -60px 50%); transform-origin: 50% 100%; }
.intro.opening .iv.heart .half { animation: none; }
.intro.opening .iv.heart .half.l { transform: translateX(-60px) rotate(-35deg) scale(1.1); opacity: 0; transition: transform 1.2s, opacity 1.2s 0.4s; }
.intro.opening .iv.heart .half.r { transform: translateX(60px) rotate(35deg) scale(1.1); opacity: 0; transition: transform 1.2s, opacity 1.2s 0.4s; }
.iv.heart .burst { position: absolute; left: 50%; top: 50%; width: 10px; height: 10px; border-radius: 50%; background: var(--g); transform: translate(-50%, -50%) scale(0); box-shadow: 0 0 60px 30px var(--g); }
.intro.opening .iv.heart .burst { animation: burst 1.6s ease-out forwards; }
@keyframes beat { 0%, 100% { transform: scale(1); } 15% { transform: scale(1.08); } 30% { transform: scale(0.98); } 45% { transform: scale(1.05); } }
@keyframes burst { to { transform: translate(-50%, -50%) scale(90); opacity: 0.9; } }

/* doors: warm wood or neon */
.iv.door { perspective: 700px; width: 180px; height: 240px; margin: auto; }
.iv.door .light { position: absolute; inset: 0; background: var(--g); box-shadow: 0 0 80px 20px var(--g); border-radius: 90px 90px 4px 4px; }
.iv.door .leaf { position: absolute; top: 0; bottom: 0; width: 50%; transition: transform 1.4s cubic-bezier(.6, 0, .2, 1); }
.iv.door .leaf.l { left: 0; transform-origin: left center; border-radius: 90px 0 0 4px; }
.iv.door .leaf.r { right: 0; transform-origin: right center; border-radius: 0 90px 4px 0; }
.iv.door.warm .leaf { background: linear-gradient(90deg, #6b3f1f, #8a5a33 50%, #6b3f1f); box-shadow: inset 0 0 0 6px #4a2a12; }
.iv.door.warm .leaf i { position: absolute; top: 52%; width: 10px; height: 10px; border-radius: 50%; background: #f2c14e; }
.iv.door.warm .leaf.l i { right: 12px; }
.iv.door.warm .leaf.r i { left: 12px; }
.iv.door.warm .light { animation: leak 2s ease-in-out infinite; }
@keyframes leak { 50% { box-shadow: 0 0 110px 34px var(--g); } }
.intro.opening .iv.door .leaf.l { transform: rotateY(-105deg); }
.intro.opening .iv.door .leaf.r { transform: rotateY(105deg); }
.intro.opening .iv.door .light { animation: burst2 1.8s ease-in forwards; }
@keyframes burst2 { to { transform: scale(9); } }
.iv.door.neon .leaf { background: #0b0718; transition: transform 1.2s cubic-bezier(.6, 0, .2, 1); }
.iv.door.neon .outline { position: absolute; inset: -6px; border: 4px solid var(--a); border-radius: 96px 96px 8px 8px; box-shadow: 0 0 18px var(--a), inset 0 0 18px var(--a), 0 0 50px var(--g); animation: flicker 2.6s infinite; }
.iv.door.neon .leaf.l, .iv.door.neon .leaf.r { border-radius: 0; }
.intro.opening .iv.door.neon .leaf.l { transform: translateX(-110%); }
.intro.opening .iv.door.neon .leaf.r { transform: translateX(110%); }
@keyframes flicker { 0%, 18%, 22%, 25%, 53%, 57%, 100% { opacity: 1; } 20%, 24%, 55% { opacity: 0.35; } }

/* storybook */
.iv.book { width: 200px; height: 150px; margin: auto; perspective: 800px; }
.iv.book .page { position: absolute; inset: 0; background: #fffaf0; border-radius: 6px; box-shadow: 0 0 60px var(--g); border: 1px solid #efe4cf; }
.iv.book .cover { position: absolute; inset: 0; background: linear-gradient(135deg, var(--a), color-mix(in srgb, var(--a) 60%, #000)); border-radius: 6px; transform-origin: left center; transition: transform 1.4s cubic-bezier(.6, 0, .2, 1); display: grid; place-items: center; font-size: 3rem; color: #fff6a8; box-shadow: inset 0 0 0 5px rgba(255, 255, 255, 0.25); }
.intro.opening .iv.book .cover { transform: rotateY(-170deg); }
.iv.book .sparkles i { position: absolute; width: 8px; height: 8px; background: var(--g); border-radius: 50%; box-shadow: 0 0 10px var(--g); left: 50%; top: 50%; opacity: 0; }
.intro.opening .iv.book .sparkles i { animation: fly 1.6s ease-out forwards; }
@keyframes fly { 0% { opacity: 1; transform: translate(0, 0); } 100% { opacity: 0; transform: translate(var(--x), var(--y)); } }

/* gift */
.iv.gift { width: 170px; height: 170px; margin: auto; }
.iv.gift .box { position: absolute; left: 10px; right: 10px; bottom: 0; height: 110px; background: var(--a); border-radius: 8px; }
.iv.gift .lid { position: absolute; left: 0; right: 0; top: 30px; height: 34px; background: color-mix(in srgb, var(--a) 80%, #fff); border-radius: 8px; z-index: 2; transition: transform 1s cubic-bezier(.3, 1.6, .5, 1); }
.iv.gift b { position: absolute; left: 50%; top: 0; bottom: 0; width: 22px; margin-left: -11px; background: var(--g); }
.iv.gift .lid::before, .iv.gift .lid::after { content: ''; position: absolute; top: -26px; width: 40px; height: 30px; border: 8px solid var(--g); border-radius: 50% 50% 0 50%; }
.iv.gift .lid::before { left: 42px; transform: rotate(-20deg); }
.iv.gift .lid::after { right: 42px; transform: scaleX(-1) rotate(-20deg); }
.iv.gift { animation: wobble 1.6s ease-in-out infinite; }
@keyframes wobble { 0%, 100% { transform: rotate(0); } 25% { transform: rotate(-4deg); } 75% { transform: rotate(4deg); } }
.intro.opening .iv.gift { animation: none; }
.intro.opening .iv.gift .lid { transform: translateY(-160px) rotate(-30deg); }
.iv.gift .confetti i { position: absolute; left: 50%; top: 40%; width: 8px; height: 14px; opacity: 0; }
.intro.opening .iv.gift .confetti i { animation: fly 1.5s ease-out forwards; }

/* candle */
.iv.candle { width: 120px; height: 220px; margin: auto; }
.iv.candle .stick { position: absolute; left: 40px; right: 40px; bottom: 0; height: 130px; background: linear-gradient(90deg, #e9e1d0, #fffaf0, #e2d8c4); border-radius: 6px; border: 1px solid #e3d8c3; }
.iv.candle .flame { position: absolute; left: 50%; bottom: 132px; width: 26px; height: 54px; margin-left: -13px; background: radial-gradient(ellipse at 50% 80%, #fff 0%, #ffe39a 30%, #ff9f2e 70%, transparent 72%); border-radius: 50% 50% 45% 45% / 60% 60% 40% 40%; animation: flame 0.18s ease-in-out infinite alternate; transform-origin: 50% 100%; }
.iv.candle .aura { position: absolute; left: 50%; bottom: 140px; width: 10px; height: 10px; margin-left: -5px; border-radius: 50%; box-shadow: 0 0 90px 50px rgba(255, 207, 106, 0.35); transition: box-shadow 1.6s; }
@keyframes flame { to { transform: scaleY(1.08) skewX(2deg); } }
.intro.opening .iv.candle .aura { box-shadow: 0 0 300px 400px rgba(255, 236, 190, 0.9); }