/* 信箱 · 样式（手机优先，纸感暖色） */

:root{
  --paper:#FAF6EF; --sheet:#FFFDF8; --line:#EAE0D2; --line-2:#E3D6C3;
  --ink:#3A3230; --ink-2:#6F6157; --ink-3:#9C8B7B;
  --clay:#B4785A; --clay-d:#9C6146; --moss:#7E8C6A; --gold:#C9A227;
  --shadow:0 1px 2px rgba(120,95,70,.03), 0 8px 24px -18px rgba(80,60,45,.35);
  --safe-b:env(safe-area-inset-bottom, 0px);
}
*{box-sizing:border-box; -webkit-tap-highlight-color:transparent}
html,body{margin:0; padding:0; background:var(--paper); color:var(--ink)}
body{
  font-family:"HarmonyOS Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  font-size:16px; line-height:1.7; -webkit-font-smoothing:antialiased;
  overscroll-behavior-y:none;
}
body::before{
  content:""; position:fixed; inset:0; z-index:0; pointer-events:none; opacity:.5;
  background-image:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='3'/><feColorMatrix values='0 0 0 0 .55 0 0 0 0 .47 0 0 0 0 .38 0 0 0 .05 0'/></filter><rect width='160' height='160' filter='url(%23n)'/></svg>");
}
.app{position:relative; z-index:1; width:100%; max-width:430px; margin:0 auto; padding:0 22px calc(84px + var(--safe-b))}
a{color:inherit; text-decoration:none}
button{font:inherit; color:inherit; background:none; border:0; padding:0; cursor:pointer}
input,textarea{font:inherit; color:inherit}
svg{display:block}

/* ---------------------------------------------------------------- 通用 */
.serif{font-family:"Songti SC","SimSun","Noto Serif SC",serif}
.hi{font-family:"Songti SC","SimSun",serif; font-size:25px; letter-spacing:.05em; font-weight:500; margin:0 0 6px; line-height:1.35}
.sub{font-size:12.5px; color:var(--ink-3); letter-spacing:.08em}
.sub b{color:var(--clay); font-weight:600}
.muted{color:var(--ink-3)}
.center{text-align:center}
.row{display:flex; align-items:center; gap:10px}

/* ---------------------------------------------------------------- 顶栏 */
.top{padding:32px 0 16px}
.search-pill{
  display:flex; align-items:center; gap:9px; height:44px; padding:0 16px;
  background:var(--sheet); border:1px solid var(--line); border-radius:999px;
  color:var(--ink-3); font-size:13.5px; margin:4px 0 14px;
}
.search-pill svg{opacity:.55; flex:0 0 auto}
.chips{display:flex; gap:8px; margin:0 0 20px; overflow-x:auto; scrollbar-width:none}
.chips::-webkit-scrollbar{display:none}
.chip{
  font-size:12.5px; padding:6px 13px; border-radius:999px; white-space:nowrap;
  border:1px solid var(--line); color:var(--ink-2);
}
.chip.on{background:var(--ink); border-color:var(--ink); color:#FBF7F0}

/* ---------------------------------------------------------------- 时间轴 */
.month{display:flex; align-items:center; gap:12px; font-size:11.5px; letter-spacing:.22em; color:var(--ink-3); margin:0 0 14px}
.month::after{content:""; flex:1; height:1px; background:linear-gradient(90deg,var(--line),transparent)}
.card{
  position:relative; display:block; background:var(--sheet);
  border:1px solid var(--line); border-radius:14px; padding:18px 18px 44px;
  margin:0 0 14px; box-shadow:var(--shadow);
}
.card .meta{display:flex; align-items:center; gap:8px; font-size:11.5px; color:var(--ink-3); letter-spacing:.06em; flex-wrap:wrap}
.dot{width:3px; height:3px; border-radius:50%; background:var(--ink-3); opacity:.6; flex:0 0 auto}
.unread{color:var(--clay); font-weight:600}
.card h2{font-family:"Songti SC","SimSun",serif; font-size:18px; line-height:1.55; letter-spacing:.03em; margin:9px 0 7px; font-weight:500}
.card p{margin:0; font-size:14.5px; line-height:1.95; color:var(--ink-2); display:-webkit-box; -webkit-line-clamp:3; -webkit-box-orient:vertical; overflow:hidden}
.card .thumb{
  margin-top:12px; width:100%; height:120px; border-radius:10px; object-fit:cover;
  background:#F2EADF; display:block;
}
.seal{
  position:absolute; right:15px; bottom:13px; width:29px; height:29px; border-radius:50%;
  background:radial-gradient(circle at 34% 28%, #CE8F6C, #B0724F 55%, #8E4E35);
  box-shadow:inset 0 -2px 5px rgba(90,45,25,.32), inset 0 2px 3px rgba(255,220,200,.32), 0 2px 6px rgba(120,70,45,.2);
  display:grid; place-items:center;
}
.seal::after{content:""; width:12px; height:12px; border:1.2px solid rgba(255,235,220,.5); border-radius:50%}
.card.read .seal{background:radial-gradient(circle at 34% 28%, #C6AE8F, #A78D6D 55%, #86704F)}

/* 未开启的空卡 */
.card.sealed{
  display:flex; flex-direction:column; align-items:center; justify-content:center;
  text-align:center; padding:18px; gap:2px; min-height:150px;
  background:linear-gradient(180deg, rgba(255,253,248,.92), rgba(250,245,236,.92));
  border-style:dashed; border-color:var(--line-2);
}
.big-seal{
  width:44px; height:44px; border-radius:50%; margin-bottom:12px;
  background:radial-gradient(circle at 34% 28%, #CE8F6C, #B0724F 55%, #8E4E35);
  box-shadow:inset 0 -2px 6px rgba(90,45,25,.32), inset 0 2px 4px rgba(255,220,200,.32), 0 3px 10px rgba(120,70,45,.18);
  display:grid; place-items:center;
  animation:breathe 4.6s ease-in-out infinite;
}
.big-seal::after{content:""; width:18px; height:18px; border:1.2px solid rgba(255,235,220,.5); border-radius:50%}
@keyframes breathe{0%,100%{transform:scale(1)}50%{transform:scale(1.05)}}
.sealed .who{font-family:"Songti SC","SimSun",serif; font-size:15.5px; letter-spacing:.05em}
.sealed .when{font-size:12.5px; color:var(--ink-3); letter-spacing:.06em; margin-top:3px}
.sealed .left{font-size:11.5px; color:var(--clay); letter-spacing:.12em; margin-top:9px}
.sealed.recalled{opacity:.75}
.sealed.recalled .big-seal{animation:none; filter:grayscale(.5)}

/* 空状态 */
.empty{padding:60px 10px; text-align:center; color:var(--ink-3); font-size:13.5px; line-height:2}
.empty .big{font-family:"Songti SC","SimSun",serif; font-size:17px; color:var(--ink-2); margin-bottom:6px}

/* ---------------------------------------------------------------- 底部 */
.tabs{
  position:fixed; left:50%; transform:translateX(-50%); bottom:0; width:100%; max-width:430px;
  display:flex; justify-content:space-around; align-items:center;
  padding:9px 0 calc(9px + var(--safe-b));
  background:rgba(250,246,239,.94); backdrop-filter:blur(12px);
  border-top:1px solid var(--line); z-index:6;
}
.tab{font-size:11.5px; color:var(--ink-3); display:flex; flex-direction:column; align-items:center; gap:2px; letter-spacing:.1em}
.tab.on{color:var(--clay)}
.tab svg{width:20px; height:20px}
.fab{
  position:fixed; right:calc(50% - 215px + 18px); bottom:calc(80px + var(--safe-b)); z-index:5;
  width:54px; height:54px; border-radius:50%; display:grid; place-items:center; color:#FFF8F0;
  background:linear-gradient(160deg,#BE8464,#A86747);
  box-shadow:0 10px 24px -8px rgba(140,85,55,.55), 0 2px 6px rgba(120,70,45,.2);
}
@media (max-width:466px){ .fab{right:18px} }

/* ---------------------------------------------------------------- 阅读 */
.reader{padding-top:22px}
.reader .back{display:inline-flex; align-items:center; gap:6px; font-size:13px; color:var(--ink-3); margin-bottom:20px}
.paper{background:var(--sheet); border:1px solid var(--line); border-radius:16px; padding:26px 22px 30px; box-shadow:var(--shadow)}
.paper .meta{font-size:11.5px; color:var(--ink-3); letter-spacing:.08em; display:flex; gap:8px; flex-wrap:wrap; align-items:center}
.paper h1{font-family:"Songti SC","SimSun",serif; font-size:24px; line-height:1.5; letter-spacing:.04em; font-weight:500; margin:14px 0 18px}
.paper .body{font-size:16.5px; line-height:2.05; color:var(--ink); white-space:pre-wrap; word-break:break-word}
.paper .body p{margin:0 0 1.05em}
.paper .sign{margin-top:22px; font-size:14px; color:var(--ink-2); text-align:right; letter-spacing:.04em}
.paper .photos{display:grid; gap:10px; margin:18px 0 4px}
.paper .photos img{width:100%; border-radius:10px; display:block; background:#F2EADF}
.paper .stamp{display:flex; justify-content:flex-end; margin-top:20px}
.banner{
  display:block; padding:12px 15px; border-radius:12px;
  background:#FBF1E6; border:1px solid #EBD3BC; color:var(--clay-d); font-size:12.5px; margin-bottom:16px; line-height:1.85;
}
.banner b{color:var(--clay-d); font-weight:600}
.banner br + br{display:none}

/* ---------------------------------------------------------------- 表单 */
.field{margin-bottom:16px}
.field label{display:block; font-size:11.5px; color:var(--ink-3); letter-spacing:.12em; margin-bottom:7px}
.input, .textarea{
  width:100%; background:var(--sheet); border:1px solid var(--line); border-radius:12px;
  padding:12px 14px; font-size:15.5px; line-height:1.8; outline:none;
}
.input:focus, .textarea:focus{border-color:#DCC4AF; box-shadow:0 0 0 3px rgba(180,120,90,.08)}
.input::placeholder, .textarea::placeholder{color:#B9A997}
.textarea{min-height:190px; resize:none; line-height:2.05; font-size:16px}
.counter{text-align:right; font-size:11px; color:var(--ink-3); margin-top:4px}

.moods{display:flex; gap:8px; flex-wrap:wrap}
.mood{
  width:42px; height:42px; border-radius:50%; display:grid; place-items:center; font-size:19px;
  border:1px solid var(--line); background:var(--sheet);
}
.mood.on{border-color:var(--clay); background:#FBF1E6; box-shadow:0 0 0 3px rgba(180,120,90,.08)}

.photos-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:8px; margin-top:10px}
.photo{position:relative; aspect-ratio:1/1; border-radius:10px; overflow:hidden; background:#F2EADF}
.photo img{width:100%; height:100%; object-fit:cover; display:block}
.photo .del{
  position:absolute; top:4px; right:4px; width:22px; height:22px; border-radius:50%;
  background:rgba(40,30,25,.55); color:#fff; font-size:13px; line-height:22px; text-align:center;
}
.add-photo{
  aspect-ratio:1/1; border-radius:10px; border:1px dashed var(--line-2); display:grid; place-items:center;
  color:var(--ink-3); font-size:22px; background:transparent;
}

.modes{display:grid; gap:9px}
.mode{
  display:flex; align-items:flex-start; gap:11px; padding:13px 14px; border:1px solid var(--line);
  border-radius:12px; background:var(--sheet); text-align:left;
}
.mode.on{border-color:var(--clay); background:#FDF6EE; box-shadow:0 0 0 3px rgba(180,120,90,.07)}
.mode .t{display:block; font-size:14.5px; letter-spacing:.03em}
.mode .d{display:block; font-size:11.5px; color:var(--ink-3); margin-top:2px; line-height:1.7}
.mode .radio{width:17px; height:17px; border-radius:50%; border:1.5px solid #D6C6B4; margin-top:3px; flex:0 0 auto; position:relative}
.mode.on .radio{border-color:var(--clay)}
.mode.on .radio::after{content:""; position:absolute; inset:3px; border-radius:50%; background:var(--clay)}

.btn{
  display:flex; align-items:center; justify-content:center; width:100%; height:48px;
  border-radius:999px; font-size:15px; letter-spacing:.1em; color:#FFF8F0;
  background:linear-gradient(160deg,#BE8464,#A86747);
  box-shadow:0 10px 24px -12px rgba(140,85,55,.6);
}
.btn:disabled{opacity:.5}
.btn.ghost{background:transparent; border:1px solid var(--line); color:var(--ink-2); box-shadow:none}
.btn.small{height:38px; font-size:13px; width:auto; padding:0 18px; letter-spacing:.06em}

.sticky-send{padding:6px 0 0}

/* ---------------------------------------------------------------- 登录 */
.login{display:flex; flex-direction:column; justify-content:center; min-height:100vh; max-width:360px; margin:0 auto; padding:0 26px 60px}
.login h1{font-family:"Songti SC","SimSun",serif; font-size:28px; letter-spacing:.2em; text-align:center; margin:0 0 8px}
.login .tip{font-size:12.5px; color:var(--ink-3); text-align:center; line-height:2; margin-bottom:28px}

/* ---------------------------------------------------------------- 其他 */
.toast{
  position:fixed; left:50%; bottom:calc(104px + var(--safe-b)); transform:translate(-50%, 12px);
  background:rgba(40,32,28,.92); color:#FFF6EE; font-size:13px; padding:9px 16px; border-radius:999px;
  opacity:0; pointer-events:none; transition:opacity .25s, transform .25s; z-index:30; max-width:80%; text-align:center;
}
.toast.show{opacity:1; transform:translate(-50%,0)}

.section-title{font-size:11.5px; letter-spacing:.2em; color:var(--ink-3); margin:26px 0 10px}
.list{background:var(--sheet); border:1px solid var(--line); border-radius:14px; overflow:hidden}
.list a, .list button{
  display:flex; width:100%; align-items:center; justify-content:space-between; gap:12px;
  padding:15px 16px; font-size:14.5px; border-bottom:1px solid var(--line); text-align:left;
}
.list > :last-child{border-bottom:0}
.list .k{color:var(--ink-3); font-size:12.5px}

.search-input{
  display:flex; align-items:center; gap:10px; height:46px; padding:0 16px;
  background:var(--sheet); border:1px solid var(--line); border-radius:999px;
}
.search-input input{flex:1; border:0; background:transparent; outline:none; font-size:14.5px}
.filters{display:flex; gap:8px; margin:12px 0 18px; flex-wrap:wrap}
.filter{font-size:12.5px; padding:6px 13px; border-radius:999px; border:1px solid var(--line); color:var(--ink-2)}
.filter.on{background:var(--ink); border-color:var(--ink); color:#FBF7F0}
mark{background:#F6E3C9; color:inherit; border-radius:3px; padding:0 1px}

.count{font-size:12px; color:var(--ink-3); margin:4px 0 16px; letter-spacing:.06em}

@media (prefers-reduced-motion: reduce){
  *{animation-duration:.001ms !important; transition-duration:.001ms !important}
}