/* ============================================================
   落雪匿名邮箱 · 前台主题
   冷调雪白 / 液态玻璃 / 细腻动效
   ============================================================ */
:root{
  --bg1:#eaf2fb; --bg2:#f7fbff; --bg3:#dce9f6;
  --ink:#1f2d3d; --ink-soft:#5b6b7d; --ink-faint:#8a99ab;
  --brand:#3f7fb8; --brand-deep:#2f6699; --brand-soft:#cfe3f5;
  --danger:#d05a63;
  --glass:rgba(255,255,255,.56);
  --glass-brd:rgba(255,255,255,.75);
  --shadow:0 18px 50px -18px rgba(47,102,153,.35);
  --radius:22px;
  --blur:18px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{-webkit-text-size-adjust:100%}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  color:var(--ink); line-height:1.6; min-height:100vh;
  background:
    radial-gradient(1200px 600px at 80% -10%, var(--bg3), transparent 60%),
    linear-gradient(160deg,var(--bg1),var(--bg2) 55%,#eef5fc);
  background-attachment:fixed; overflow-x:hidden;
}
#snow{position:fixed;inset:0;pointer-events:none;z-index:0}
.aurora{position:fixed;inset:0;z-index:0;pointer-events:none;
  background:radial-gradient(600px 300px at 15% 20%,rgba(160,205,240,.35),transparent 70%),
            radial-gradient(700px 380px at 90% 70%,rgba(190,220,242,.4),transparent 70%);
  animation:drift 22s ease-in-out infinite alternate;}
@keyframes drift{from{transform:translate3d(-2%,-1%,0)}to{transform:translate3d(2%,2%,0)}}

.wrap{position:relative;z-index:2;max-width:880px;margin:0 auto;padding:18px 18px 60px}

/* 顶栏 */
.site-header{position:relative;z-index:3;max-width:880px;margin:0 auto;padding:22px 18px 6px;
  display:flex;align-items:center;justify-content:space-between}
.brand{display:flex;align-items:center;gap:12px}
.brand-mark{width:42px;height:42px;display:grid;place-items:center;font-size:22px;color:#fff;border-radius:13px;
  background:linear-gradient(145deg,#6aa6d6,#3f7fb8);box-shadow:0 8px 20px -6px rgba(63,127,184,.6)}
.brand-text strong{display:block;font-size:17px;letter-spacing:.5px}
.brand-text small{display:block;color:var(--ink-faint);font-size:11.5px}
.ghost-link{font-size:13px;color:var(--ink-soft);text-decoration:none;padding:8px 14px;border-radius:999px;
  background:var(--glass);border:1px solid var(--glass-brd);backdrop-filter:blur(var(--blur));transition:.25s}
.ghost-link:hover{color:var(--brand-deep);transform:translateY(-1px)}

/* 玻璃容器 */
.glass{background:var(--glass);border:1px solid var(--glass-brd);
  backdrop-filter:blur(var(--blur)) saturate(1.2);-webkit-backdrop-filter:blur(var(--blur)) saturate(1.2);
  box-shadow:var(--shadow);border-radius:var(--radius)}

.hero{text-align:center;padding:34px 10px 22px}
.hero h1{font-size:30px;font-weight:800;letter-spacing:.5px}
.hero h1 span{background:linear-gradient(120deg,var(--brand),#7fb2dc);-webkit-background-clip:text;background-clip:text;color:transparent}
.hero p{margin-top:10px;color:var(--ink-soft);font-size:14.5px}

.card{padding:22px;margin-top:16px;animation:rise .6s cubic-bezier(.2,.8,.2,1) both}
@keyframes rise{from{opacity:0;transform:translateY(16px)}to{opacity:1;transform:none}}

/* 邮箱卡片 */
.mb-top{display:flex;align-items:center;justify-content:space-between}
.mb-label{font-size:12.5px;color:var(--ink-faint);letter-spacing:1px}
.mb-type{font-size:11.5px;padding:3px 10px;border-radius:999px;background:var(--brand-soft);color:var(--brand-deep)}
.mb-address-row{margin:12px 0}
.mb-address{display:flex;align-items:center;gap:10px;width:100%;text-align:left;cursor:pointer;
  font-size:clamp(17px,4.6vw,24px);font-weight:700;letter-spacing:.3px;color:var(--brand-deep);
  background:rgba(255,255,255,.6);border:1px dashed var(--brand-soft);border-radius:14px;padding:14px 16px;transition:.2s}
.mb-address:hover{background:#fff;border-style:solid}
.mb-address .ico-copy{width:18px;height:18px;fill:var(--brand);margin-left:auto;flex:none}

.countdown{margin:6px 0 16px}
.cd-bar{height:8px;border-radius:99px;background:rgba(63,127,184,.12);overflow:hidden}
.cd-bar i{display:block;height:100%;width:100%;border-radius:99px;
  background:linear-gradient(90deg,#7fb2dc,var(--brand));transition:width 1s linear}
.cd-bar i.warn{background:linear-gradient(90deg,#e8b15f,#d05a63)}
.cd-meta{display:flex;gap:8px;align-items:baseline;margin-top:7px;font-size:12.5px;color:var(--ink-faint)}
#cdText{font-variant-numeric:tabular-nums;font-weight:700;color:var(--brand-deep);font-size:14px}

.mb-actions{display:flex;flex-wrap:wrap;gap:10px}
.btn{appearance:none;border:1px solid var(--glass-brd);cursor:pointer;font-size:13.5px;font-weight:600;
  padding:10px 16px;border-radius:12px;background:rgba(255,255,255,.7);color:var(--ink);
  display:inline-flex;align-items:center;gap:6px;transition:.2s;font-family:inherit}
.btn:hover{transform:translateY(-1px);box-shadow:0 8px 18px -8px rgba(47,102,153,.5)}
.btn:active{transform:translateY(0)}
.btn .b-ico{font-size:14px;line-height:1}
.btn-primary{background:linear-gradient(145deg,#5b97cc,var(--brand));color:#fff;border-color:transparent}
.btn-ghost{background:transparent}
.btn-ghost.danger{color:var(--danger)}
.btn[disabled]{opacity:.55;pointer-events:none}

/* 标签页 */
.panel{padding:0;overflow:hidden}
.tabs{display:flex;border-bottom:1px solid rgba(63,127,184,.14);padding:6px 6px 0;background:rgba(255,255,255,.35)}
.tab{appearance:none;border:0;background:transparent;cursor:pointer;padding:13px 18px;font-size:14.5px;font-weight:600;
  color:var(--ink-soft);font-family:inherit;position:relative;display:flex;align-items:center;gap:7px}
.tab.active{color:var(--brand-deep)}
.tab.active::after{content:"";position:absolute;left:14px;right:14px;bottom:-1px;height:3px;border-radius:3px;
  background:linear-gradient(90deg,#7fb2dc,var(--brand))}
.badge{font-style:normal;font-size:11px;background:var(--danger);color:#fff;border-radius:99px;min-width:18px;height:18px;
  display:inline-grid;place-items:center;padding:0 5px}
.badge.hidden{display:none}
.tabpane{display:none;padding:16px;min-height:280px}
.tabpane.active{display:block;animation:fade .35s ease}
@keyframes fade{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}

/* 邮件列表 */
.mail-item{display:flex;gap:12px;padding:14px 12px;border-radius:14px;cursor:pointer;transition:.18s;border:1px solid transparent}
.mail-item:hover{background:rgba(255,255,255,.7);border-color:var(--glass-brd)}
.mail-item + .mail-item{margin-top:4px}
.mail-dot{width:9px;height:9px;border-radius:50%;background:var(--brand);margin-top:9px;flex:none}
.mail-item.read .mail-dot{background:transparent;border:1.5px solid #c3d2e0}
.mail-main{flex:1;min-width:0}
.mail-line1{display:flex;justify-content:space-between;gap:10px}
.mail-from{font-weight:700;font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.mail-time{font-size:11.5px;color:var(--ink-faint);flex:none}
.mail-subj{font-size:13.5px;color:var(--ink-soft);white-space:nowrap;overflow:hidden;text-overflow:ellipsis;margin-top:2px}
.mail-item.read{opacity:.62}
.dir-tag{font-size:10.5px;padding:1px 7px;border-radius:6px;background:var(--brand-soft);color:var(--brand-deep);margin-right:6px}

.empty{text-align:center;padding:46px 20px;color:var(--ink-faint)}
.empty-ico{font-size:38px;margin-bottom:8px}
.empty p{font-size:14px}.empty small{font-size:12px;opacity:.8}

/* 写信 */
.compose label{display:block;font-size:12.5px;color:var(--ink-soft);font-weight:600;margin-bottom:14px}
.compose input,.compose textarea{display:block;width:100%;margin-top:7px;padding:12px 14px;font-size:14px;font-family:inherit;
  border:1px solid rgba(63,127,184,.2);border-radius:12px;background:rgba(255,255,255,.75);color:var(--ink);resize:vertical;transition:.2s}
.compose input:focus,.compose textarea:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3px rgba(63,127,184,.12);background:#fff}
.compose-foot{display:flex;align-items:center;justify-content:space-between;margin-top:6px}
.limit-hint{font-size:12.5px;color:var(--ink-faint)}

/* 特性 */
.features{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:14px;margin-top:22px}
.feat{padding:20px 18px;border-radius:18px;transition:.25s}
.feat:hover{transform:translateY(-3px)}
.feat span{font-size:24px}.feat h3{font-size:15px;margin:8px 0 4px}.feat p{font-size:12.5px;color:var(--ink-soft)}

/* 页脚 */
.site-foot{margin-top:26px;font-size:12.5px;color:var(--ink-faint);text-align:center}
.site-foot details{background:var(--glass);border:1px solid var(--glass-brd);border-radius:14px;padding:12px 16px;text-align:left;backdrop-filter:blur(10px)}
.site-foot summary{cursor:pointer;font-weight:600;color:var(--ink-soft)}
.site-foot details p{margin-top:8px;line-height:1.7}
.copyright{margin-top:14px}

/* 阅读弹层 */
.reader-mask{position:fixed;inset:0;z-index:50;display:none;place-items:center;padding:18px;
  background:rgba(31,45,61,.32);backdrop-filter:blur(6px)}
.reader-mask.show{display:grid;animation:fade .25s}
.reader{width:min(720px,100%);max-height:86vh;overflow:auto;padding:0;animation:rise .35s cubic-bezier(.2,.8,.2,1)}
.reader-head{display:flex;justify-content:space-between;position:sticky;top:0;background:rgba(255,255,255,.82);
  backdrop-filter:blur(12px);padding:12px 16px;border-bottom:1px solid rgba(63,127,184,.12)}
.reader-head button{border:0;background:transparent;font-size:13.5px;font-weight:600;cursor:pointer;color:var(--brand-deep);font-family:inherit}
.reader-head .reader-del{color:var(--danger)}
.reader h2{padding:18px 20px 6px;font-size:19px;line-height:1.4}
.r-meta{padding:0 20px;display:flex;flex-wrap:wrap;gap:6px 16px;font-size:12.5px;color:var(--ink-faint)}
.r-attach{padding:12px 20px 0;display:flex;flex-wrap:wrap;gap:8px}
.att-chip{font-size:12px;padding:7px 12px;border-radius:10px;background:var(--brand-soft);color:var(--brand-deep);text-decoration:none}
.r-body{padding:16px 20px 26px;font-size:14.5px;line-height:1.8;word-break:break-word}
.r-body iframe{width:100%;border:0;min-height:320px;background:#fff;border-radius:10px}
.r-body pre{white-space:pre-wrap;font-family:inherit}

/* toast */
.toast{position:fixed;left:50%;bottom:34px;transform:translate(-50%,20px);z-index:80;opacity:0;pointer-events:none;
  background:rgba(31,45,61,.92);color:#fff;padding:11px 20px;border-radius:999px;font-size:13.5px;transition:.3s;max-width:88vw;text-align:center}
.toast.show{opacity:1;transform:translate(-50%,0)}
.toast.err{background:rgba(208,90,99,.95)}

.closed{text-align:center;padding:46px 20px}.closed-emoji{font-size:40px}.closed h2{margin:10px 0 6px}

@media (max-width:560px){
  .hero h1{font-size:24px}
  .card{padding:18px}
  .mb-actions .btn{flex:1;justify-content:center;padding:10px 8px}
  .tab{padding:12px 13px;font-size:13.5px}
}