:root{color-scheme:light;--paper:#ffffee;--ink:#228567;--muted:#8c8a74;--rose:#cb5473;--line:#dddac0;--tree-shift-x:-200px;--serif:"STKaiti","KaiTi","Songti SC","SimSun",serif}
*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--serif);-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}button{font:inherit}button,a{-webkit-tap-highlight-color:transparent}a:focus-visible,button:focus-visible{outline:2px solid var(--ink);outline-offset:5px}[hidden]{display:none!important}
.masthead{width:100%;max-width:1240px;margin:auto;padding:27px 44px;display:flex;align-items:center;justify-content:space-between;font:12px/1.5 "Microsoft YaHei",sans-serif;letter-spacing:.13em;color:var(--muted)}
.letter-layout{max-width:1160px;min-height:720px;margin:0 auto;display:grid;grid-template-columns:minmax(0,550px) minmax(0,460px);gap:70px;align-items:center;padding:0 30px 35px}
.tree-panel{min-width:0;align-self:center}#tree-viewport{position:relative;width:100%;overflow:hidden}#tree-stage{position:relative;width:680px;height:680px;transform-origin:top left}canvas{position:absolute;left:0;top:0;width:1100px;height:680px;pointer-events:none}#ground-canvas{z-index:0;transform:translateX(-200px)}#static-canvas{z-index:1;transform:translateX(-200px)}#canvas{z-index:2}#heart-links{position:absolute;inset:0;z-index:3;pointer-events:none}
.heart-link{position:absolute;width:52px;height:52px;display:grid;place-items:center;transform:translate(-50%,-50%);pointer-events:auto;border-radius:50%;color:#c72b55}.heart-link svg{width:29px;height:29px;fill:currentColor;filter:drop-shadow(0 0 4px #fff);animation:heartbeat 2.8s ease-in-out infinite}.heart-link:before{content:"";position:absolute;inset:5px;border:1px solid #fff8;border-radius:50%;animation:ripple 2.8s ease-in-out infinite}.heart-link:nth-child(2) svg{animation-delay:.7s}.heart-link:nth-child(3) svg{animation-delay:1.4s}.heart-link:nth-child(4) svg{animation-delay:2.1s}.heart-link:hover svg,.heart-link:focus-visible svg{fill:#a8003c;filter:drop-shadow(0 0 7px #fff);scale:1.18}
.tree-hint{text-align:center;margin:17px 0 0;color:var(--muted);font-size:14px;letter-spacing:.06em;min-height:22px}.tree-hint a{border-bottom:1px dotted #b9a695;padding-bottom:3px}
.letter-panel{padding-top:35px}.eyebrow{font:10px/1.5 "Microsoft YaHei",sans-serif;letter-spacing:.24em;color:#a29174;margin:0 0 23px}h1{font-size:32px;font-weight:400;letter-spacing:.09em;margin:0 0 26px}#letter{font-size:17px;line-height:1.95;letter-spacing:.025em;min-height:349px}#letter p{margin:0 0 14px}.signature{padding-top:7px}.signature span{font-size:14px;color:#7c8a70}.clock-box{border-top:1px solid var(--line);margin-top:30px;padding-top:21px;color:var(--muted)}.clock-box p{font-size:15px;margin:0 0 10px}#clock{white-space:nowrap;font-size:14px;font-family:var(--serif);color:#807c69;font-variant-numeric:tabular-nums}.digit{font-family:Georgia,serif;font-size:28px;color:#4b5145}#days{font-size:43px;margin-right:3px}.clock-box .since{font:10px/1.5 "Microsoft YaHei",sans-serif;letter-spacing:.16em;margin-top:12px;color:#aaa089}.page-footer{text-align:center;font-size:12px;letter-spacing:.13em;color:#aaa089;padding:20px 20px 30px}.noscript{text-align:center}
.typewriter-cursor{color:var(--rose);animation:blink 1s steps(2,start) infinite}.typewriter-cursor--done{display:none}
@keyframes heartbeat{0%,100%{transform:scale(1)}50%{transform:scale(1.14)}}@keyframes ripple{0%,100%{opacity:.25;transform:scale(.85)}50%{opacity:.9;transform:scale(1.12)}}@keyframes blink{to{visibility:hidden}}
/* The memory page uses the same paper, ink and restrained letter layout. */
.memory-page{max-width:1000px;margin:auto;padding:30px 28px 45px}.memory-nav{display:flex;justify-content:space-between;align-items:center;font-size:14px;color:var(--muted)}.memory-nav a{color:var(--ink)}.memory-intro{text-align:center;margin:35px 0 23px}.memory-intro .eyebrow{margin-bottom:12px}.memory-intro h1{margin-bottom:12px}.memory-intro p{font-size:15px;line-height:1.8;margin:0;color:var(--muted)}.game-tools{display:flex;justify-content:space-between;align-items:center;max-width:640px;margin:0 auto 17px;font-size:14px}.text-button{border:0;background:none;color:var(--ink);cursor:pointer;border-bottom:1px dotted #9baf8b;padding:4px 0}.board{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:15px;max-width:640px;margin:auto}.card{position:relative;aspect-ratio:1.12;padding:5px;border:1px solid #dedbc6;background:#fffef7;border-radius:3px;cursor:pointer;box-shadow:0 3px 9px #51482c0b;transition:transform .2s,border-color .2s}.card:hover:not(:disabled){transform:translateY(-3px);border-color:#bdc7a2}.card-back{position:absolute;inset:5px;display:grid;place-items:center;border:1px solid #e9e5cf;background:repeating-linear-gradient(0deg,transparent,transparent 18px,#c9cba31a 19px);color:#c68586;font:32px Georgia,serif}.card-back:after{content:"♡"}.card img{display:none;width:100%;height:100%;object-fit:cover}.card.is-open img,.card.is-matched img{display:block}.card.is-open .card-back,.card.is-matched .card-back{display:none}.card.is-matched{border-color:#84a78c;cursor:default}.card.is-matched:after{content:"♥";position:absolute;right:7px;bottom:7px;color:#fff;background:#538b70;border-radius:50%;width:20px;height:20px;font:12px/20px sans-serif}.memory-caption{text-align:center;color:var(--muted);font-size:13px;margin:20px 0}.ending{max-width:640px;margin:30px auto 0;border-top:1px solid var(--line);padding:30px 15px;text-align:center}.ending h2{font-weight:400;line-height:1.7;font-size:27px}.ending p{font-size:16px;line-height:1.9}.ending a{display:inline-block;margin-top:12px;border-bottom:1px dotted var(--ink);padding-bottom:5px}
@media(min-width:1400px){.home{min-height:100vh;display:flex;flex-direction:column}.letter-layout{flex:1;width:100%}}
@media(max-width:1000px){.letter-layout{gap:24px;grid-template-columns:minmax(0,1.1fr) minmax(0,1fr);padding-inline:22px;min-height:650px}.letter-panel{padding-top:0}h1{font-size:28px}#letter{font-size:16px}.digit{font-size:23px}#days{font-size:36px}#clock{font-size:12px}}
@media(max-width:700px){.masthead{padding:21px 23px;font-size:10px;letter-spacing:.06em}.letter-layout{display:flex;flex-direction:column;gap:27px;padding:0 24px 24px;min-height:0}.tree-panel{width:min(100%,420px)}.tree-hint{font-size:12px;margin-top:13px}.letter-panel{width:100%;max-width:440px;padding:13px 3px 0}.eyebrow{margin-bottom:16px}h1{font-size:29px}#letter{font-size:17px;min-height:0;line-height:1.95}.clock-box{margin-top:28px}.digit{font-size:26px}#days{font-size:40px}#clock{font-size:13px}.memory-page{padding:24px 17px}.memory-nav{font-size:12px}.memory-intro{margin-top:35px}.memory-intro h1{font-size:27px;letter-spacing:.02em}.memory-intro p{font-size:13px}.board{gap:8px}.card{aspect-ratio:.84;padding:3px}.card-back{inset:3px;font-size:27px}.game-tools{font-size:13px}.ending h2{font-size:23px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}

/* A second letter is unlocked after all eight memories are matched. */
.ending .unlock-note{color:var(--muted);font-size:15px}
.envelope-button{position:relative;display:flex;flex-direction:column;align-items:center;gap:12px;width:min(100%,370px);margin:27px auto 15px;padding:30px 20px 24px;background:#fffdf2;border:1px solid #dfd8ba;border-radius:3px;color:var(--ink);box-shadow:0 8px 24px #7264470c;cursor:pointer;transition:transform .25s,box-shadow .25s;font-size:18px}
.envelope-button:before{content:"";position:absolute;inset:7px;border:1px solid #e8e0c8;pointer-events:none}.envelope-button:hover{transform:translateY(-3px);box-shadow:0 12px 28px #72644717}
.envelope-heart{color:var(--rose);font:36px/1 Georgia,serif}.envelope-caption{font-size:12px;letter-spacing:.14em;color:var(--muted)}
.ending:focus,.confession-letter:focus{outline:none}.ending:focus-visible,.confession-letter:focus-visible{outline:2px solid #87a98b;outline-offset:8px}
.confession-letter{margin:35px 0 14px;padding:38px 38px 30px;border:1px solid #e3dcc2;background:linear-gradient(135deg,#fffef8,#fffdf0);box-shadow:0 10px 32px #6c63430a;text-align:left;animation:unfold-letter .6s ease both;scroll-margin-top:25px}
.confession-heading{padding-bottom:20px;margin-bottom:25px;border-bottom:1px solid #e5dfc9}.ending .confession-letter .confession-heading .eyebrow{font-size:10px;margin-bottom:14px}.confession-heading h2{font-size:26px;line-height:1.7;margin:0;letter-spacing:.03em}
.ending .confession-letter p{font-size:17px;line-height:2.05;margin:0 0 20px;overflow-wrap:anywhere}.ending .confession-letter .confession-salutation{font-size:23px;color:#547b60;margin-bottom:19px}
.letter-chapter{margin-top:30px}.letter-chapter h3{font-size:15px;font-weight:400;letter-spacing:.1em;color:#a37570;padding-left:13px;border-left:2px solid #d8ada0;margin:0 0 16px}
.ending .confession-letter .confession-promise{margin-top:33px;padding-top:25px;border-top:1px solid #e5dfc9;color:#ac5c70;font-size:20px;line-height:1.95}
.ending .confession-letter .confession-signature{text-align:right;color:var(--muted);font-size:14px;margin:28px 0 0}.ending .ending-home{font-size:14px;line-height:1.8}
@keyframes unfold-letter{from{opacity:0;transform:translateY(16px)}to{opacity:1;transform:translateY(0)}}
@media(max-width:700px){.ending{padding:25px 0}.ending h2{font-size:23px}.confession-letter{padding:28px 21px 25px;margin-top:27px}.confession-heading h2{font-size:23px}.ending .confession-letter p{font-size:16px;line-height:2}.ending .confession-letter .confession-salutation{font-size:22px}.letter-chapter h3{font-size:14px;letter-spacing:.04em}.ending .confession-letter .confession-promise{font-size:18px}.ending .confession-letter .confession-signature{font-size:13px}.envelope-button{font-size:17px}}
@media(prefers-reduced-motion:reduce){.confession-letter{animation:none}.envelope-button{transition:none}}


/* A quiet date puzzle before the letter opens. */
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.date-entry{min-height:100svh;display:flex;flex-direction:column;align-items:center;padding:35px 20px 23px}.date-gate{width:100%;max-width:640px;text-align:center;margin:auto;padding:45px 0 60px}.date-gate .eyebrow{margin-bottom:27px;letter-spacing:.2em}.gate-heart{display:block;font:55px/1 Georgia,serif;color:#c77c85;margin-bottom:25px}.date-gate h1{font-size:32px;letter-spacing:.07em;margin:0 0 47px;line-height:1.65}.date-fieldset{border:0;margin:0;padding:0;min-width:0}.date-digits{display:flex;gap:13px;justify-content:center}.date-digit{width:34px;min-width:0;height:46px;padding:0 0 6px;border:0;border-bottom:1px solid #b8b99b;border-radius:0;background:transparent;color:var(--ink);font:28px/1.2 Georgia,serif;text-align:center;caret-color:var(--rose);outline:none;transition:border-color .2s}.date-digit:focus{border-bottom:2px solid var(--ink)}.date-digit[aria-invalid="true"]{border-color:#c77c85}.date-gate .date-help{font-size:13px;letter-spacing:.08em;color:var(--muted);margin:25px 0 0}.date-error{min-height:24px;color:#ad6578;font-size:13px;line-height:1.7;margin:12px 0 19px}.date-submit{border:1px solid #c6ccb3;padding:13px 28px;background:#fffef5;color:var(--ink);font-size:16px;letter-spacing:.08em;cursor:pointer;border-radius:2px;transition:background .2s,transform .2s}.date-submit span{margin-left:13px}.date-submit:hover{background:#f3f4e3;transform:translateY(-2px)}.gate-footer{font-size:12px;letter-spacing:.1em;color:#aaa089;text-align:center;padding-top:25px}
@media(max-width:600px){.date-gate h1{font-size:25px;letter-spacing:.025em;margin-bottom:36px}.date-gate .eyebrow{font-size:9px;letter-spacing:.14em}.date-digits{gap:10px}.date-digit{width:28px;height:42px;font-size:26px}.date-gate{padding:35px 0 45px}.gate-heart{font-size:47px;margin-bottom:23px}}
@media(max-width:350px){.date-digits{gap:8px}.date-digit{width:25px}.date-gate h1{font-size:22px}}