:root {
  --ink: #102535;
  --navy: #0c2535;
  --navy-2: #173f55;
  --blue: #2c7ca5;
  --paper: #fffdf8;
  --canvas: #f2efe7;
  --warm: #df642b;
  --gold: #e1b533;
  --line: #d8d8d0;
  --muted: #657783;
  --ok: #18845f;
  --danger: #b94935;
  --shadow: 0 20px 60px rgba(13, 37, 52, .12);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--canvas);
  font-family: "Microsoft YaHei", "Noto Sans CJK SC", system-ui, sans-serif;
}
button, input, textarea { font: inherit; }

.report-header {
  min-height: 82px;
  padding: 12px clamp(18px, 3.5vw, 64px);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  color: #fff;
  background: var(--navy);
}
.report-brand { display: flex; align-items: center; gap: 14px; color: #fff; text-decoration: none; }
.brand-mark { width: 46px; height: 46px; display: grid; place-items: center; border: 1px solid var(--gold); color: var(--gold); font: 28px Georgia, serif; }
.report-brand strong { display: block; font-size: 20px; }
.report-brand small { display: block; margin-top: 4px; color: #9edaf6; letter-spacing: .08em; font-size: 11px; }
.header-actions { display: flex; align-items: center; gap: 18px; }
.header-flow { display: flex; align-items: center; gap: 8px; color: #c4d5dd; font-size: 12px; white-space: nowrap; }
.header-flow i { width: 18px; height: 1px; background: #557181; }
.privacy-note { color: #a9c0cd; font-size: 13px; }
.header-link { color: #fff; border: 1px solid #416478; padding: 10px 16px; text-decoration: none; }

.report-shell { width: min(1800px, calc(100% - 32px)); margin: 0 auto; padding-top: 20px; }

.workspace { display: grid; grid-template-columns: minmax(500px, .88fr) minmax(650px, 1.12fr); gap: 20px; align-items: start; padding-bottom: 48px; }
.form-panel, .preview-panel { background: #fff; border: 1px solid #deddd7; box-shadow: var(--shadow); }
.form-panel { padding: clamp(22px, 3vw, 38px); }
.panel-heading { display: flex; justify-content: space-between; align-items: center; gap: 18px; margin-bottom: 24px; }
.panel-heading > div { display: flex; align-items: center; gap: 12px; }
.panel-heading h2 { margin: 0; font-family: SimSun, STSong, serif; font-size: 25px; font-weight: 500; }
.panel-heading.compact { margin-bottom: 12px; }
.section-number { display: grid; place-items: center; width: 33px; height: 33px; background: var(--warm); color: #fff; font: 12px Georgia, serif; }
.autosave-state { color: var(--ok); font-size: 12px; }
.section-divider { height: 1px; margin: 32px 0; background: #e4e3dd; }
.section-help { margin: 0 0 18px; color: var(--muted); line-height: 1.7; font-size: 13px; }

.field-grid { display: grid; gap: 18px; }
.two-columns { grid-template-columns: repeat(2, minmax(0, 1fr)); }
label { display: grid; gap: 8px; color: #334c5a; font-size: 14px; }
input, textarea {
  width: 100%;
  border: 1px solid #cfd5d6;
  background: #fbfbf8;
  color: var(--ink);
  border-radius: 0;
  padding: 12px 13px;
  outline: none;
  transition: border-color .2s, box-shadow .2s;
}
input:focus, textarea:focus { border-color: var(--blue); box-shadow: 0 0 0 3px rgba(44, 124, 165, .12); }
input.invalid { border-color: var(--danger); background: #fff8f6; }
textarea { resize: vertical; line-height: 1.7; }

.text-button { border: 0; background: none; color: var(--blue); cursor: pointer; padding: 6px; }
.reading-table-wrap { overflow-x: auto; border: 1px solid #dedfdc; }
.reading-table { width: 100%; border-collapse: collapse; min-width: 500px; }
.reading-table th { padding: 12px 9px; background: #eff4f5; color: #49606c; font-size: 12px; font-weight: 600; }
.reading-table td { padding: 9px; text-align: center; border-top: 1px solid #e3e4e0; }
.reading-table input { min-width: 145px; padding: 9px; text-align: center; font-family: Consolas, monospace; }
.row-state { font-size: 12px; color: #89959b; }
.row-state.ready { color: var(--ok); }

.check-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 11px; margin-bottom: 24px; }
.check-grid label { display: flex; align-items: flex-start; gap: 9px; padding: 12px; background: #f6f6f1; line-height: 1.5; cursor: pointer; }
.check-grid input { width: 17px; height: 17px; margin-top: 2px; accent-color: var(--blue); }
.wide-field { margin-top: 6px; }
.form-actions { display: grid; grid-template-columns: .65fr 1fr 1.25fr; gap: 10px; margin-top: 24px; }
.button { min-height: 48px; border: 1px solid var(--navy); cursor: pointer; padding: 11px 14px; }
.button.primary { color: #fff; background: var(--navy); }
.button.secondary { color: var(--navy); background: #e8f1f4; }
.button.ghost { color: #526773; background: #fff; border-color: #cdd3d3; }
.button:disabled { opacity: .42; cursor: not-allowed; }
.form-message { min-height: 22px; margin: 12px 0 0; color: var(--danger); font-size: 13px; }
.form-message.success { color: var(--ok); }
.pdf-fallback { display: inline-block; color: var(--blue); font-size: 13px; text-underline-offset: 3px; }
.pdf-fallback[hidden] { display: none; }

.preview-panel { position: sticky; top: 16px; overflow: hidden; background: #dfe3e1; }
.preview-toolbar { min-height: 54px; padding: 0 20px; display: flex; align-items: center; justify-content: space-between; background: var(--navy); color: #fff; font-size: 13px; }
.preview-toolbar > div { display: flex; align-items: center; gap: 9px; }
.preview-toolbar > span { color: #9fc5d7; }
.preview-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--gold); box-shadow: 0 0 0 4px rgba(225,181,51,.15); }
.pdf-preview-scroll { max-height: calc(100vh - 128px); min-height: 700px; padding: 18px; overflow-y: auto; overscroll-behavior: contain; scrollbar-gutter: stable; background: #cfd5d8; }
.pdf-preview-page { width: min(100%, 820px); margin: 0 auto 22px; background: #fffdf8; box-shadow: 0 8px 28px rgba(20, 39, 50, .22); }
.pdf-preview-page:last-child { margin-bottom: 0; }
.pdf-preview-page canvas { display: block; width: 100%; height: auto; }
.preview-empty { min-height: 630px; display: grid; align-content: center; justify-items: center; padding: 40px; text-align: center; color: #64757d; background: rgba(255,255,255,.5); border: 1px dashed #9da9ae; }
.preview-empty span { width: 64px; height: 64px; display: grid; place-items: center; margin-bottom: 18px; border-radius: 50%; color: #fff; background: var(--navy); font: bold 16px Arial, sans-serif; }
.preview-empty strong { color: var(--navy); font-size: 20px; }
.preview-empty p { max-width: 420px; line-height: 1.8; font-size: 13px; }
.paper { width: calc(100% - 36px); max-width: 760px; aspect-ratio: 210 / 297; min-height: 900px; margin: 18px auto 30px; padding: 44px 48px; background: var(--paper); box-shadow: 0 12px 30px rgba(28,41,48,.16); font-family: SimSun, STSong, serif; }
.paper-kicker { padding-bottom: 9px; border-bottom: 2px solid var(--navy); color: var(--warm); font: 11px "Microsoft YaHei", sans-serif; letter-spacing: .12em; }
.paper h2 { margin: 28px 0 22px; text-align: center; font-size: 25px; font-weight: 600; }
.paper-meta { display: grid; grid-template-columns: repeat(2, 1fr); gap: 9px 22px; margin-bottom: 27px; font-size: 13px; }
.paper-meta span { border-bottom: 1px solid #aaa; padding: 4px 0; }
.paper h3 { margin: 19px 0 9px; font-size: 16px; }
.paper h4 { margin: 15px 0 7px; font-size: 14px; }
.paper p { margin: 0; text-indent: 2em; line-height: 1.75; font-size: 13px; }
.preview-data-grid { display: grid; grid-template-columns: .64fr 1.36fr; gap: 18px; align-items: center; }
.paper table { width: 100%; border-collapse: collapse; font-size: 11px; }
.paper th, .paper td { border: 1px solid #99a2a4; padding: 4px 6px; text-align: center; }
.paper th { background: #eef1ef; }
#fitChart { width: 100%; height: auto; background: #fff; border: 1px solid #d9dcda; }
.result-cards { display: grid; grid-template-columns: repeat(4, 1fr); border: 1px solid #b5bec0; }
.result-cards > div { padding: 10px 5px; text-align: center; border-right: 1px solid #cbd0d0; }
.result-cards > div:last-child { border-right: 0; }
.result-cards small, .result-cards strong, .result-cards span { display: block; }
.result-cards small { min-height: 30px; color: #62737a; font: 10px "Microsoft YaHei", sans-serif; }
.result-cards strong { color: var(--navy); font: 18px Georgia, serif; }
.result-cards span { color: #62737a; font-size: 10px; }
.equation { margin-top: 9px !important; text-align: center; text-indent: 0 !important; font-family: "Times New Roman", SimSun, serif; }
.conclusion-placeholder { color: #68777d; }
.ai-analysis-box { margin-top: 15px; padding: 14px 15px; background: #edf5f7; border-left: 4px solid var(--blue); }
.ai-analysis-title { display: flex; align-items: center; gap: 9px; margin-bottom: 8px; font: 12px "Microsoft YaHei", sans-serif; color: var(--navy); }
.ai-analysis-title span { width: 27px; height: 27px; display: grid; place-items: center; border-radius: 50%; background: var(--navy); color: #fff; font: bold 10px Arial, sans-serif; }
.ai-analysis-box p { text-indent: 0; color: #34505e; }
.report-footer { padding: 28px; text-align: center; background: var(--navy); color: #9fb4c0; font-size: 12px; }

@media (max-width: 1080px) {
  .header-flow { display: none; }
  .workspace { grid-template-columns: 1fr; }
  .preview-panel { position: static; }
  .pdf-preview-scroll { max-height: 78vh; min-height: 580px; }
  .paper { min-height: 0; }
}

@media (max-width: 680px) {
  .report-header { padding: 12px 14px; }
  .report-brand strong { font-size: 13px; }
  .report-brand small { font-size: 9px; }
  .brand-mark { width: 38px; height: 38px; font-size: 23px; }
  .privacy-note { display: none; }
  .header-link { padding: 8px 10px; font-size: 12px; }
  .report-shell { width: min(100% - 20px, 1800px); padding-top: 10px; }
  .workspace { display: block; }
  .form-panel { padding: 20px 14px; }
  .two-columns, .check-grid { grid-template-columns: 1fr; }
  .form-actions { grid-template-columns: 1fr; }
  .preview-panel { margin-top: 18px; }
  .pdf-preview-scroll { min-height: 460px; max-height: 72vh; padding: 7px; }
  .pdf-preview-page { margin-bottom: 10px; }
  .paper { width: calc(100% - 14px); margin: 7px auto 14px; padding: 24px 17px; }
  .paper h2 { font-size: 19px; }
  .paper-meta { grid-template-columns: 1fr; }
  .preview-data-grid { grid-template-columns: 1fr; }
  .result-cards { grid-template-columns: repeat(2, 1fr); }
  .result-cards > div:nth-child(2) { border-right: 0; }
  .result-cards > div:nth-child(-n+2) { border-bottom: 1px solid #cbd0d0; }
}