/* File-unavailable notice. Content branches and smart-back behavior remain in PHP. */
.file-missing-page{margin:0;min-height:100vh;min-height:100dvh;box-sizing:border-box;display:flex;align-items:flex-start;justify-content:center;padding:clamp(80px,14vh,160px) 24px 44px;background:radial-gradient(ellipse at 15% 10%,#edf2fc,transparent 55%),#f6f8fc;color:#27344c;font-family:system-ui,-apple-system,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;font-size:14px;line-height:1.8;-webkit-text-size-adjust:100%;text-size-adjust:100%}
.file-missing-page *{box-sizing:border-box}
.error-container{position:relative;display:grid;grid-template-columns:64px minmax(0,1fr);align-items:start;gap:26px;width:100%;max-width:700px;padding:40px;border:1px solid #e1e7f2;border-radius:20px;background:linear-gradient(120deg,#fff 45%,#f5f7ff);box-shadow:0 12px 36px #233c680c;overflow:hidden}
.error-container::before{content:"";position:absolute;inset:0 0 auto;height:3px;background:linear-gradient(90deg,#74a1f4,#afa1df,#96cbd5)}
.error-icon{display:grid;place-items:center;width:64px;height:64px;margin-top:4px;background:#fff6e8;border:1px solid #f3e6cd;border-radius:18px;color:#bb8946}
.error-icon svg{display:block;width:34px;height:34px}
.error-content{min-width:0}
.error-eyebrow{font-size:11px;letter-spacing:.6px;color:#8d9bb3;margin:0 0 9px}
.error-title{margin:0 0 16px;font-size:27px;font-weight:700;line-height:1.45;color:#1b2c49;letter-spacing:0}
.error-message{margin:0;color:#78859c;font-size:14px;line-height:1.95;overflow-wrap:anywhere}
.error-detail{display:block;width:100%;margin:16px 0 0;padding:14px 17px;border:1px solid #e5eaf4;border-radius:11px;background:#f0f4fc;color:#72819a;font-size:13px;text-align:left}
.error-detail>div+div{margin-top:5px}
.action-buttons{display:flex;align-items:center;gap:12px;flex-wrap:wrap;padding-top:25px;margin-top:24px;border-top:1px solid #e9edf5}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:7px;min-height:44px;padding:10px 18px;border:1px solid transparent;border-radius:10px;font:500 13px/1.5 system-ui,-apple-system,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;text-decoration:none;cursor:pointer;transition:background .15s,border-color .15s,box-shadow .15s;touch-action:manipulation}
.btn svg{display:block;flex-shrink:0;width:16px;height:16px}
.btn-secondary{background:#fff;border-color:#dfe6f1;color:#687b98}
.btn-secondary:hover{border-color:#bed0ec;background:#f7faff}
.btn-primary{background:#2563eb;border-color:#2563eb;color:#fff;box-shadow:0 3px 10px #2563eb15}
.btn-primary:hover{background:#1e56d3;border-color:#1e56d3}
.btn:focus-visible{outline:3px solid #9ebcfa;outline-offset:4px}
@media(max-width:640px){
  .file-missing-page{padding:clamp(42px,9vh,80px) 16px 30px}
  .error-container{grid-template-columns:minmax(0,1fr);gap:22px;padding:28px 24px;border-radius:17px;max-width:440px}
  .error-icon{width:54px;height:54px;border-radius:15px;margin:0}.error-icon svg{width:30px;height:30px}
  .error-eyebrow{font-size:10px;margin-bottom:8px}.error-title{font-size:24px;margin-bottom:13px}
  .error-message{font-size:13px}.error-detail{padding:13px 14px;font-size:12px;margin-top:15px}
  .action-buttons{gap:10px;padding-top:21px;margin-top:21px}.btn{flex:1;min-width:0;padding:11px 10px;white-space:nowrap;font-size:12px}
}
@media(max-width:360px){.error-container{padding:25px 21px}.action-buttons{flex-direction:column;align-items:stretch}.btn{width:100%;flex:auto}}
@media(prefers-reduced-motion:reduce){.btn{transition:none}}