*,
*::before,
*::after { box-sizing: border-box; margin: 0; padding: 0; }

:root,
[data-theme="dark"] {
  color-scheme: dark;
  --bg-deep: #050505;
  --bg-card: rgba(21, 20, 21, 0.88);
  --border: rgba(255, 255, 255, 0.07);
  --border-active: rgba(212, 184, 122, 0.55);
  --text: #f5f2eb;
  --text-soft: rgba(245, 242, 235, 0.62);
  --text-muted: rgba(245, 242, 235, 0.36);
  --accent: #d4b87a;
  --accent-light: #f0e0bc;
  --accent-dim: #b8923f;
  --accent-glow: rgba(212, 184, 122, 0.18);
  --lavender: #b8a0e8;
  --lavender-soft: rgba(168, 148, 232, 0.14);
  --gold: #d4b87a;
  --gold-soft: rgba(212, 184, 122, 0.12);
  --eyebrow: rgba(168, 148, 232, 0.85);
  --surface-input: rgba(0, 0, 0, 0.28);
  --surface-muted: rgba(0, 0, 0, 0.2);
  --surface-hover: rgba(255, 255, 255, 0.04);
  --surface-selected: rgba(212, 184, 122, 0.07);
  --surface-hint: rgba(255, 255, 255, 0.03);
  --progress-track: rgba(255, 255, 255, 0.06);
  --dot-idle: rgba(255, 255, 255, 0.12);
  --hover-border: rgba(255, 255, 255, 0.14);
  --tag-hover-border: rgba(255, 255, 255, 0.16);
  --divider-subtle: rgba(255, 255, 255, 0.06);
  --panel-inset: rgba(255, 255, 255, 0.03);
  --panel-shadow: 0 24px 64px rgba(0, 0, 0, 0.45);
  --foot-cn: rgba(232, 212, 168, 0.9);
  --foot-en: rgba(168, 148, 232, 0.65);
  --foot-nav: rgba(232, 212, 168, 0.72);
  --foot-legal: rgba(245, 242, 235, 0.28);
  --foot-gradient: rgba(212, 184, 122, 0.03);
  --foot-line: rgba(212, 184, 122, 0.35);
  --foot-line-end: rgba(184, 160, 232, 0.25);
  --choice-note: rgba(212, 184, 122, 0.75);
  --choice-note-border: rgba(212, 184, 122, 0.2);
  --compliance-bg: rgba(212, 184, 122, 0.06);
  --compliance-border: rgba(212, 184, 122, 0.25);
  --bf-hint-bg: rgba(212, 168, 83, 0.08);
  --bf-hint-border: rgba(212, 168, 83, 0.22);
  --pill-bg: rgba(255, 255, 255, 0.03);
  --bg-ambient-1: rgba(184, 160, 232, 0.08);
  --bg-ambient-2: rgba(212, 184, 122, 0.06);
  --bg-gradient-top: #0a0a0a;
  --orb-a: rgba(212, 184, 122, 0.07);
  --orb-b: rgba(184, 160, 232, 0.06);
  --grid-color: rgba(255, 255, 255, 0.5);
  --grid-opacity: 0.035;
  --btn-primary-text: #151415;
  --logo-display-dark: block;
  --logo-display-light: none;
  --theme-toggle-show: sun;
  --radius: 16px;
  --radius-sm: 10px;
  --font-display: "Noto Serif SC", "Songti SC", Georgia, serif;
  --font-body: "Inter", "DM Sans", system-ui, sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

[data-theme="light"] {
  color-scheme: light;
  --bg-deep: #faf8f4;
  --bg-card: rgba(255, 255, 255, 0.94);
  --border: rgba(26, 20, 12, 0.09);
  --border-active: rgba(154, 119, 40, 0.55);
  --text: #1a1612;
  --text-soft: rgba(26, 22, 18, 0.72);
  --text-muted: rgba(26, 22, 18, 0.46);
  --accent: #b8923f;
  --accent-light: #8a6f2e;
  --accent-dim: #96782e;
  --accent-glow: rgba(184, 146, 63, 0.16);
  --lavender: #7c6aad;
  --lavender-soft: rgba(124, 106, 173, 0.1);
  --gold: #b8923f;
  --gold-soft: rgba(184, 146, 63, 0.1);
  --eyebrow: #6b5b9a;
  --surface-input: #ffffff;
  --surface-muted: rgba(26, 20, 12, 0.025);
  --surface-hover: rgba(184, 146, 63, 0.05);
  --surface-selected: rgba(184, 146, 63, 0.09);
  --surface-hint: rgba(26, 20, 12, 0.025);
  --progress-track: rgba(26, 20, 12, 0.07);
  --dot-idle: rgba(26, 20, 12, 0.14);
  --hover-border: rgba(154, 119, 40, 0.28);
  --tag-hover-border: rgba(154, 119, 40, 0.32);
  --divider-subtle: rgba(26, 20, 12, 0.07);
  --panel-inset: rgba(255, 255, 255, 0.85);
  --panel-shadow: 0 20px 48px rgba(92, 74, 40, 0.08), 0 2px 8px rgba(26, 20, 12, 0.04);
  --foot-cn: #5c4a1a;
  --foot-en: #6b5b9a;
  --foot-nav: #8a6f2e;
  --foot-legal: rgba(26, 22, 18, 0.42);
  --foot-gradient: rgba(184, 146, 63, 0.04);
  --foot-line: rgba(184, 146, 63, 0.35);
  --foot-line-end: rgba(124, 106, 173, 0.28);
  --choice-note: rgba(138, 111, 46, 0.88);
  --choice-note-border: rgba(184, 146, 63, 0.22);
  --compliance-bg: rgba(184, 146, 63, 0.07);
  --compliance-border: rgba(184, 146, 63, 0.22);
  --bf-hint-bg: rgba(184, 146, 63, 0.08);
  --bf-hint-border: rgba(184, 146, 63, 0.2);
  --pill-bg: rgba(255, 255, 255, 0.72);
  --bg-ambient-1: rgba(184, 146, 63, 0.07);
  --bg-ambient-2: rgba(124, 106, 173, 0.06);
  --bg-gradient-top: #fffdf9;
  --orb-a: rgba(212, 184, 122, 0.14);
  --orb-b: rgba(168, 148, 232, 0.1);
  --grid-color: rgba(26, 20, 12, 0.35);
  --grid-opacity: 0.045;
  --btn-primary-text: #1a1408;
  --logo-display-dark: none;
  --logo-display-light: block;
  --theme-toggle-show: moon;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  min-height: 100vh;
  font-family: var(--font-body);
  color: var(--text);
  background: var(--bg-deep);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  display: flex;
  flex-direction: column;
  transition: background 0.4s var(--ease), color 0.35s var(--ease);
}

/* ── Ambient background ── */
.brief-bg {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(ellipse 70% 50% at 50% -5%, var(--bg-ambient-1), transparent 55%),
    radial-gradient(ellipse 45% 35% at 100% 80%, var(--bg-ambient-2), transparent 50%),
    linear-gradient(180deg, var(--bg-gradient-top) 0%, var(--bg-deep) 45%, var(--bg-deep) 100%);
  transition: background 0.45s var(--ease);
}

.brief-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  animation: orbFloat 18s var(--ease) infinite alternate;
}

.brief-orb-a {
  width: 420px;
  height: 420px;
  top: -8%;
  left: -6%;
  background: var(--orb-a);
}

.brief-orb-b {
  width: 320px;
  height: 320px;
  bottom: 10%;
  right: -4%;
  background: var(--orb-b);
  animation-delay: -6s;
}

.brief-grid {
  position: absolute;
  inset: 0;
  opacity: var(--grid-opacity);
  background-image:
    linear-gradient(var(--grid-color) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-color) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black, transparent);
  transition: opacity 0.4s var(--ease);
}

@keyframes orbFloat {
  from { transform: translate(0, 0) scale(1); }
  to { transform: translate(24px, 18px) scale(1.06); }
}

/* ── Header / footer ── */
.brief-header {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px clamp(20px, 4vw, 48px);
  padding-top: max(20px, env(safe-area-inset-top));
}

.brief-logo {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
  color: inherit;
  line-height: 0;
}

.brief-logo-img {
  display: block;
  height: 32px;
  width: auto;
}

.brief-logo--dark { display: var(--logo-display-dark); }
.brief-logo--light { display: var(--logo-display-light); }

.brief-header-meta {
  display: flex;
  align-items: center;
  gap: 10px;
}

.brief-pill {
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.06em;
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--text-muted);
  background: var(--pill-bg);
}

/* ── Theme toggle ── */
.brief-theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  height: 34px;
  min-width: 34px;
  padding: 0 10px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--pill-bg);
  color: var(--text-soft);
  cursor: pointer;
  font-family: inherit;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.06em;
  transition: border-color 0.2s, background 0.2s, color 0.2s, box-shadow 0.2s;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}

.brief-theme-toggle:hover {
  border-color: var(--border-active);
  color: var(--accent-light);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.brief-theme-icon {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

.brief-theme-icon--sun { display: block; }
.brief-theme-icon--moon { display: none; }

[data-theme="light"] .brief-theme-icon--sun { display: none; }
[data-theme="light"] .brief-theme-icon--moon { display: block; }

[data-theme="dark"] .brief-theme-label::after { content: "明亮"; }
[data-theme="light"] .brief-theme-label::after { content: "暗色"; }

.brief-theme-label { font-size: 11px; }

@media (max-width: 560px) {
  .brief-logo-img {
    height: 28px;
  }
  .brief-theme-label { display: none; }
  .brief-theme-toggle { padding: 0; width: 34px; }
}

.brief-foot {
  position: relative;
  z-index: 2;
  margin-top: auto;
  padding: 0 clamp(16px, 4vw, 48px) max(24px, env(safe-area-inset-bottom));
}

.brief-foot-inner {
  max-width: 720px;
  margin: 0 auto;
  padding: 28px 0 8px;
  border-top: 1px solid var(--border);
  background: linear-gradient(180deg, transparent, var(--foot-gradient));
}

.brief-foot-inner::before {
  content: "";
  display: block;
  height: 1px;
  margin: -29px 0 28px;
  background: linear-gradient(90deg, transparent, var(--foot-line), var(--foot-line-end), transparent);
}

.brief-foot-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}

.brief-foot-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: inherit;
}

.brief-foot-mark {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
}

.brief-foot-lockup {
  display: flex;
  flex-direction: column;
  gap: 2px;
  line-height: 1.05;
}

.brief-foot-cn {
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--foot-cn);
}

.brief-foot-en {
  font-size: 8px;
  font-weight: 500;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--foot-en);
}

.brief-foot-tagline {
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--text-muted);
  text-align: right;
  max-width: 220px;
  line-height: 1.5;
}

.brief-foot-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  margin-bottom: 16px;
}

.brief-foot-nav a {
  font-size: 12px;
  font-weight: 500;
  color: var(--foot-nav);
  text-decoration: none;
  letter-spacing: 0.02em;
  transition: color 0.2s;
}

.brief-foot-nav a:hover {
  color: var(--accent-light);
}

.brief-foot-legal {
  font-size: 10px;
  letter-spacing: 0.06em;
  color: var(--foot-legal);
  line-height: 1.5;
}

@media (max-width: 560px) {
  .brief-foot-top {
    flex-direction: column;
    align-items: flex-start;
  }
  .brief-foot-tagline {
    text-align: left;
    max-width: none;
  }
}

/* ── Main shell ── */
.brief-shell {
  position: relative;
  z-index: 10;
  flex: 1;
  width: 100%;
  max-width: 720px;
  margin: 0 auto;
  padding: 8px clamp(16px, 4vw, 24px) 32px;
}

.brief-loading {
  text-align: center;
  padding: 80px 0;
  color: var(--text-muted);
  font-size: 14px;
}

/* ── Progress ── */
.brief-progress {
  margin-bottom: 28px;
}

.brief-progress-top {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 12px;
}

.brief-step-label {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent-light);
}

.brief-step-count {
  font-size: 12px;
  color: var(--text-muted);
}

.brief-progress-track {
  height: 3px;
  border-radius: 999px;
  background: var(--progress-track);
  overflow: hidden;
}

.brief-progress-fill {
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, #b8923f, #d4b87a, #b8a0e8);
  transition: width 0.55s var(--ease);
  box-shadow: 0 0 20px var(--accent-glow);
}

.brief-dots {
  display: flex;
  gap: 6px;
  margin-top: 14px;
  justify-content: center;
}

.brief-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--dot-idle);
  transition: all 0.35s var(--ease);
}

.brief-dot.done { background: var(--accent-dim); }
.brief-dot.active {
  width: 20px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--accent), var(--lavender));
  box-shadow: 0 0 12px var(--accent-glow);
}

/* ── Card panel ── */
.brief-panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: clamp(28px, 5vw, 40px);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  box-shadow:
    0 0 0 1px var(--panel-inset) inset,
    var(--panel-shadow);
  transition: background 0.4s var(--ease), border-color 0.35s, box-shadow 0.4s;
}

.brief-panel-enter {
  animation: panelIn 0.4s var(--ease) both;
}

@media (max-width: 768px) {
  .brief-panel {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }
  [data-theme="dark"] .brief-panel {
    background: rgba(21, 20, 21, 0.96);
  }
  [data-theme="light"] .brief-panel {
    background: rgba(255, 255, 255, 0.98);
  }
}

@keyframes panelIn {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

.brief-eyebrow {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--eyebrow);
  margin-bottom: 10px;
}

.brief-title {
  font-family: var(--font-display);
  font-size: clamp(28px, 5vw, 36px);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.01em;
  margin-bottom: 10px;
}

.brief-sub {
  font-size: 14px;
  line-height: 1.65;
  color: var(--text-soft);
  margin-bottom: 28px;
  max-width: 52ch;
}

/* ── Form fields ── */
.brief-field {
  margin-bottom: 20px;
}

.brief-field label {
  display: block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-soft);
  margin-bottom: 8px;
}

.brief-choices.cols-1 { grid-template-columns: 1fr; }

.brief-field-hint {
  font-size: 12px;
  line-height: 1.65;
  color: var(--text-muted);
  margin: -4px 0 12px;
}

.brief-field-hint strong {
  color: var(--accent-light);
  font-weight: 600;
}

.brief-exp-badge {
  display: inline-block;
  margin-left: 6px;
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--accent-light);
  background: var(--gold-soft);
  border: 1px solid rgba(212, 184, 122, 0.22);
  vertical-align: middle;
}

.brief-field label span.req { color: var(--accent-light); margin-left: 2px; }

.brief-field input[type="text"],
.brief-field input[type="email"],
.brief-field input[type="tel"],
.brief-field input[type="url"],
.brief-field textarea,
.brief-field select,
.brief-bench-row input {
  width: 100%;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--surface-input);
  color: var(--text);
  font-family: inherit;
  /* iOS Safari：低于 16px 聚焦时会自动 zoom */
  font-size: 16px;
  transition: border-color 0.2s, box-shadow 0.2s, background 0.25s;
  outline: none;
  -webkit-appearance: none;
  appearance: none;
}

.brief-field textarea {
  min-height: 96px;
  resize: vertical;
  line-height: 1.55;
}

.brief-field input:focus,
.brief-field textarea:focus,
.brief-field select:focus {
  border-color: var(--border-active);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.brief-field input::placeholder,
.brief-field textarea::placeholder {
  color: var(--text-muted);
}

.brief-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

@media (max-width: 560px) {
  .brief-row { grid-template-columns: 1fr; }
  .brief-pill { display: none; }
}

/* ── Choice cards ── */
.brief-choices {
  display: grid;
  gap: 10px;
}

.brief-choices.cols-2 { grid-template-columns: repeat(2, 1fr); }
.brief-choices.cols-3 { grid-template-columns: repeat(3, 1fr); }

@media (max-width: 560px) {
  .brief-choices.cols-2,
  .brief-choices.cols-3 { grid-template-columns: 1fr; }
}

.brief-choice {
  display: block;
  width: 100%;
  font: inherit;
  color: inherit;
  text-align: left;
  position: relative;
  cursor: pointer;
  padding: 16px 18px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--surface-muted);
  transition: border-color 0.2s, background 0.2s, box-shadow 0.2s;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  min-height: 52px;
}

.brief-choice:active {
  transform: scale(0.985);
}

.brief-choice:hover {
  border-color: var(--hover-border);
  background: var(--surface-hover);
}

.brief-choice.selected {
  border-color: var(--border-active);
  background: var(--surface-selected);
  box-shadow: 0 0 24px var(--accent-glow);
}

.brief-choice-title {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 4px;
}

.brief-choice-desc {
  font-size: 12px;
  line-height: 1.5;
  color: var(--text-muted);
}

.brief-choice.selected .brief-choice-desc { color: var(--text-soft); }

.brief-choice-note {
  margin-top: 8px;
  padding-top: 8px;
  border-top: 1px solid var(--divider-subtle);
  font-size: 11px;
  line-height: 1.45;
  color: var(--choice-note);
}

.brief-choice.selected .brief-choice-note {
  color: var(--accent-light);
  border-top-color: var(--choice-note-border);
}

.brief-compliance {
  margin-top: 16px;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--compliance-border);
  background: var(--compliance-bg);
  font-size: 12px;
  line-height: 1.55;
  color: var(--text-soft);
}

.brief-compliance strong {
  display: block;
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 6px;
}

/* ── Tag multi-select ── */
.brief-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.brief-tag {
  cursor: pointer;
  padding: 10px 14px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 500;
  border: 1px solid var(--border);
  background: var(--surface-muted);
  color: var(--text-soft);
  transition: border-color 0.2s, background 0.2s, color 0.2s;
  user-select: none;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  font-family: inherit;
}

.brief-tag:hover { border-color: var(--tag-hover-border); }

.brief-tag.selected {
  border-color: var(--border-active);
  background: var(--surface-selected);
  color: var(--accent-light);
}

/* ── Benchmark rows ── */
.brief-bench-row {
  display: flex;
  gap: 8px;
  margin-bottom: 8px;
}

.brief-bench-row input { flex: 1; }

.brief-bench-add {
  font-size: 14px;
  color: var(--accent);
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px 0;
  min-height: 44px;
  font-family: inherit;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  opacity: 0.85;
}

.brief-bench-add:hover { opacity: 1; text-decoration: underline; }

/* ── Review summary ── */
.brief-review {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  margin-bottom: 20px;
}

.brief-review-row {
  display: flex;
  gap: 12px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  font-size: 13px;
}

.brief-review-row:last-child { border-bottom: none; }

.brief-review-key {
  flex: 0 0 88px;
  color: var(--text-muted);
  font-size: 12px;
}

.brief-review-val {
  flex: 1;
  color: var(--text-soft);
  line-height: 1.45;
  word-break: break-word;
}

/* ── Nav buttons ── */
.brief-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.brief-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 24px;
  min-height: 48px;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: transform 0.2s, box-shadow 0.2s;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}

.brief-btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.brief-btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid transparent;
}

.brief-btn-ghost:hover:not(:disabled) {
  color: var(--text-soft);
  border-color: var(--border);
}

.brief-btn-primary {
  background: linear-gradient(135deg, #c9a862, #d4b87a 45%, #b8a0e8);
  color: var(--btn-primary-text);
  box-shadow: 0 4px 24px var(--accent-glow);
}

.brief-btn-primary:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 8px 32px rgba(212, 184, 122, 0.28);
}

.brief-btn-gold {
  background: linear-gradient(135deg, #b8923f, var(--gold));
  color: #1a1408;
  box-shadow: 0 4px 24px var(--gold-soft);
}

/* ── Welcome hero ── */
.brief-hero {
  text-align: center;
  padding: 12px 0 8px;
}

.brief-hero .brief-title {
  font-size: clamp(32px, 6vw, 44px);
  margin-bottom: 16px;
}

.brief-hero .brief-sub {
  margin: 0 auto 32px;
  text-align: center;
}

.brief-stats {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-bottom: 36px;
  flex-wrap: wrap;
}

.brief-stat-num {
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 600;
  color: var(--accent-light);
  line-height: 1;
}

.brief-stat-label {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 4px;
  letter-spacing: 0.06em;
}

/* ── Success screen ── */
.brief-success {
  text-align: center;
  padding: 20px 0;
}

.brief-success-icon {
  width: 72px;
  height: 72px;
  margin: 0 auto 24px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
  background: var(--gold-soft);
  border: 1px solid rgba(212, 184, 122, 0.35);
  box-shadow: 0 0 40px var(--accent-glow);
  animation: successPop 0.6s var(--ease) both;
}

@keyframes successPop {
  from { transform: scale(0.6); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

.brief-ref {
  display: inline-block;
  margin: 20px 0 28px;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  font-family: ui-monospace, monospace;
  font-size: 15px;
  letter-spacing: 0.08em;
  color: var(--accent-light);
  background: var(--gold-soft);
  border: 1px solid rgba(212, 184, 122, 0.28);
}

.brief-success-note {
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-soft);
  max-width: 40ch;
  margin: 0 auto;
}

.brief-error {
  margin-top: 12px;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: #fca5a5;
  background: rgba(220, 38, 38, 0.12);
  border: 1px solid rgba(220, 38, 38, 0.25);
}

.brief-mode-hint {
  margin-top: 18px;
  padding: 14px 16px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  line-height: 1.65;
  color: var(--text-soft);
  background: var(--surface-hint);
  border: 1px solid var(--border);
}

.brief-mode-hint-bf {
  background: var(--bf-hint-bg);
  border-color: var(--bf-hint-border);
}

.brief-mode-hint-bf strong {
  display: block;
  color: var(--gold);
  font-size: 12px;
  letter-spacing: 0.06em;
  margin-bottom: 6px;
}

.brief-foot-dot { opacity: 0.4; }

.brief-mode-hint em {
  font-style: normal;
  color: var(--accent-light);
  font-weight: 600;
}

.brief-section-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gold);
  margin: 8px 0 14px;
  padding-top: 8px;
  border-top: 1px solid var(--border);
}

.brief-sub strong {
  color: var(--text);
  font-weight: 600;
}

.brief-toast {
  position: fixed;
  bottom: max(88px, calc(env(safe-area-inset-bottom) + 72px));
  left: 50%;
  transform: translateX(-50%);
  z-index: 100;
  max-width: min(90vw, 420px);
  padding: 12px 18px;
  border-radius: var(--radius-sm);
  font-size: 16px;
  color: #fecaca;
  background: rgba(127, 29, 29, 0.92);
  border: 1px solid rgba(248, 113, 113, 0.35);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  pointer-events: none;
}

.brief-toast[hidden] { display: none !important; }