/* ============================================================
   PETRA — Evolutionary Geometry Design System
   Concept: phylogenetic branch motif as visual DNA.
   Cold stone canvas + viridian stamp + amber mutation signal.

   Branch motif appears in 6 places:
     1. Logo glyph (nav + footer)
     2. Hero signature phylogenetic tree SVG
     3. Section dividers (branch-seam)
     4. Section header branch-ticks
     5. Loading state (branch-growth animation)
     6. Form-focus fork on underline right tip

   Shared by: index.html, classify.html, tree.html
   ============================================================ */

/* ── Google Fonts (system fallbacks for China) ── */
@import url('https://fonts.googleapis.com/css2?family=Bricolage+Grotesque:opsz,wght@12..96,500;12..96,700;12..96,800&family=IBM+Plex+Sans:wght@400;500;600&family=IBM+Plex+Mono:wght@400;500&display=swap');

/* ── Design Tokens ── */
:root {
  /* Canvas — COLD stone, NOT warm paper */
  --canvas:       #f5f5f4;
  --canvas-2:     #eeeeec;
  /* Ink — zinc scale, near-black to tertiary */
  --ink:          #18181b;
  --ink-2:        #3f3f46;
  --ink-3:        #71717a;
  /* Rules — hairlines, 1px only */
  --rule:         #d4d4d8;
  /* Viridian — THE stamp accent. Biology/lab green. At most 1-2 per viewport. */
  --viridian:     #047857;
  --viridian-10:  rgba(4,120,87,0.10);
  --viridian-15:  rgba(4,120,87,0.15);
  /* Amber — MUTATION hot-signal ONLY. Dots, Δlogit, predict semantic, errors. Never decorative. */
  --amber:        #d97706;
  --amber-10:     rgba(217,119,6,0.10);
  --amber-15:     rgba(217,119,6,0.15);
  /* Base-pair coloring (genomics convention, adjusted for viridian palette) */
  --base-A:       #16a34a;
  --base-T:       #d97706;
  --base-C:       #2563eb;
  --base-G:       #9333ea;
  /* Typography */
  --font-display: "Bricolage Grotesque", "Helvetica Neue", Arial, sans-serif;
  --font-body:    "IBM Plex Sans", system-ui, -apple-system, sans-serif;
  --font-mono:    "IBM Plex Mono", "SF Mono", Menlo, monospace;
  /* Spacing — generous vertical rhythm */
  --space-xs:  4px;
  --space-sm:  8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  --space-4xl: 96px;
  --space-5xl: 120px;
  /* Transitions */
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
  --dur-fast: 150ms;
  --dur: 250ms;
  --dur-slow: 500ms;
}

/* ── Reset & Base ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { height: 100%; scroll-behavior: smooth; }
body {
  height: 100%;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--canvas);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ── Typography ── */
h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(48px, 6.5vw, 80px);
  line-height: 1.0;
  letter-spacing: -0.03em;
  color: var(--ink);
}
h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(26px, 3.5vw, 40px);
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--ink);
}
h3 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 22px;
  line-height: 1.1;
  letter-spacing: -0.01em;
  color: var(--ink);
}
h4 {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 18px;
  line-height: 1.2;
  color: var(--ink);
}
p {
  max-width: 66ch;
  color: var(--ink-2);
}
a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: var(--rule);
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
  transition: color var(--dur-fast), text-decoration-color var(--dur-fast);
}
a:hover {
  color: var(--viridian);
  text-decoration-color: var(--viridian);
}

code, pre, .mono {
  font-family: var(--font-mono);
  font-size: 0.88em;
}

/* ── Base-pair colored spans ── */
.base-A { color: var(--base-A); font-family: var(--font-mono); }
.base-T { color: var(--base-T); font-family: var(--font-mono); }
.base-C { color: var(--base-C); font-family: var(--font-mono); }
.base-G { color: var(--base-G); font-family: var(--font-mono); }

/* ════════════════════════════════════════════════════════
   CONCEPT GRAPHIC LANGUAGE — PHYLOGENETIC BRANCH MOTIF
   ════════════════════════════════════════════════════════ */

/* ── 1. BRANCH GLYPH (logo, wordmark companion) ── */
.branch-glyph {
  display: inline-block;
  width: 22px;
  height: 18px;
  vertical-align: middle;
  margin-right: 8px;
  flex-shrink: 0;
}
.branch-glyph svg {
  display: block;
  width: 100%;
  height: 100%;
}
.branch-glyph line,
.branch-glyph path {
  stroke: var(--ink);
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.branch-glyph circle {
  fill: var(--amber);
  opacity: 0.9;
}

/* ── 2. HERO PHYLOGENETIC TREE SVG ── */
.phylo-tree {
  display: block;
  width: 100%;
  max-width: 680px;
  margin: var(--space-2xl) auto var(--space-xl);
  overflow: visible;
}
.phylo-tree .trunk,
.phylo-tree .branch {
  stroke: var(--ink-3);
  stroke-width: 1.5;
  stroke-linecap: round;
  fill: none;
}
.phylo-tree .tip-dot {
  fill: var(--amber);
  opacity: 0;
}
.phylo-tree .tip-label {
  font-family: var(--font-mono);
  font-size: 8px;
  fill: var(--ink-3);
  letter-spacing: 0.03em;
  opacity: 0;
}
.phylo-tree .trunk {
  stroke-dasharray: 1000;
  stroke-dashoffset: 1000;
  animation: phylo-draw-trunk 0.5s ease-out forwards;
  animation-delay: 0.05s;
}
.phylo-tree .branch {
  stroke-dasharray: 300;
  stroke-dashoffset: 300;
  animation: phylo-draw-branch 0.5s ease-out forwards;
}
.phylo-tree .tip-dot {
  animation: phylo-fade-in 0.4s ease-out forwards;
}
.phylo-tree .tip-label {
  animation: phylo-fade-in 0.4s ease-out forwards;
}

@keyframes phylo-draw-trunk {
  to { stroke-dashoffset: 0; }
}
@keyframes phylo-draw-branch {
  to { stroke-dashoffset: 0; }
}
@keyframes phylo-fade-in {
  from { opacity: 0; transform: translateY(4px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── 3. BRANCH-SEAM DIVIDER ── */
.branch-seam {
  display: flex;
  align-items: center;
  gap: 0;
  margin: var(--space-lg) 0;
  width: 100%;
}
.branch-seam::before,
.branch-seam::after {
  content: '';
  flex: 1;
  border-top: 1px solid var(--rule);
}
.branch-seam .seam-node {
  flex-shrink: 0;
  width: 32px;
  height: 14px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}
.branch-seam .seam-node svg {
  display: block;
  width: 100%;
  height: 100%;
}
.branch-seam .seam-node line,
.branch-seam .seam-node path {
  stroke: var(--ink-3);
  stroke-width: 1.2;
  stroke-linecap: round;
}

/* ── 4. SECTION HEADER with branch-tick ── */
.section-header {
  display: flex;
  align-items: baseline;
  gap: 0;
  margin-bottom: var(--space-sm);
}
.section-num {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink-3);
  letter-spacing: 0.04em;
  flex-shrink: 0;
  margin-right: 4px;
}
.branch-tick {
  display: inline-block;
  width: 14px;
  height: 16px;
  flex-shrink: 0;
  margin-right: 6px;
  margin-left: 4px;
  vertical-align: middle;
  align-self: center;
  position: relative;
  top: 1px;
}
.branch-tick svg {
  display: block;
  width: 100%;
  height: 100%;
}
.branch-tick line,
.branch-tick path {
  stroke: var(--ink-3);
  stroke-width: 1.3;
  stroke-linecap: round;
}

/* ── 5. BRANCH-GROWTH LOADER (replaces spinner) ── */
.branch-loader {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 18px;
  vertical-align: middle;
  margin-left: var(--space-md);
}
.branch-loader svg {
  display: block;
  width: 100%;
  height: 100%;
}
.branch-loader .bl-trunk {
  stroke: var(--viridian);
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-dasharray: 40;
  stroke-dashoffset: 40;
  animation: bl-grow-trunk 0.8s ease-in-out infinite;
}
.branch-loader .bl-branch {
  stroke: var(--viridian);
  stroke-width: 1.2;
  stroke-linecap: round;
  stroke-dasharray: 20;
  stroke-dashoffset: 20;
  animation: bl-grow-branch 0.8s ease-in-out infinite;
}
.branch-loader .bl-branch:nth-child(2) { animation-delay: 0.15s; }
.branch-loader .bl-branch:nth-child(3) { animation-delay: 0.3s; }
.branch-loader .bl-dot {
  fill: var(--amber);
  opacity: 0;
  animation: bl-dot-appear 0.8s ease-in-out infinite;
}
.branch-loader .bl-dot:nth-child(4) { animation-delay: 0.35s; }
.branch-loader .bl-dot:nth-child(5) { animation-delay: 0.5s; }

@keyframes bl-grow-trunk {
  0%   { stroke-dashoffset: 40; }
  40%  { stroke-dashoffset: 0; }
  60%  { stroke-dashoffset: 0; }
  100% { stroke-dashoffset: 40; }
}
@keyframes bl-grow-branch {
  0%   { stroke-dashoffset: 20; }
  40%  { stroke-dashoffset: 20; }
  70%  { stroke-dashoffset: 0; }
  85%  { stroke-dashoffset: 0; }
  100% { stroke-dashoffset: 20; }
}
@keyframes bl-dot-appear {
  0%   { opacity: 0; }
  55%  { opacity: 0; }
  70%  { opacity: 1; }
  85%  { opacity: 1; }
  100% { opacity: 0; }
}

/* ── 6. FORM-FOCUS FORK (underline prongs on input focus) ── */
.fork-input-wrap {
  position: relative;
  display: flex;
  flex-direction: column;
}
/* The fork prong decoration appears on the right end of the focused underline */
.fork-input-wrap::after {
  content: '';
  position: absolute;
  bottom: 0;
  right: -1px;
  width: 12px;
  height: 14px;
  pointer-events: none;
  opacity: 0;
  transition: opacity var(--dur-fast);
  background: 
    linear-gradient(to bottom left,  transparent 49%, var(--viridian) 49%, var(--viridian) 51%, transparent 51%) 0 0 / 6px 7px no-repeat,
    linear-gradient(to bottom right, transparent 49%, var(--viridian) 49%, var(--viridian) 51%, transparent 51%) 6px 0 / 6px 7px no-repeat;
}
.fork-input-wrap:focus-within::after {
  opacity: 1;
}

/* ════════════════════════════════════════════════════════ */

/* ── Layout containers ── */
.container-prose {
  width: min(720px, 90%);
  margin: 0 auto;
  padding: 0 var(--space-md);
  position: relative;
  z-index: 1;
}
.container-wide {
  width: min(1080px, 90%);
  margin: 0 auto;
  padding: 0 var(--space-md);
  position: relative;
  z-index: 1;
}
.section-block {
  margin-bottom: var(--space-4xl);
}

/* ── Navbar — thin, stone, 1px bottom rule ── */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px var(--space-xl);
  background: var(--canvas);
  border-bottom: 1px solid var(--rule);
}
.navbar-wordmark {
  display: flex;
  align-items: center;
  gap: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  letter-spacing: 0.02em;
  color: var(--ink);
  text-decoration: none;
}
.navbar-wordmark:hover {
  color: var(--ink);
  text-decoration: none;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}
.nav-links a {
  color: var(--ink-2);
  font-size: 13px;
  font-weight: 500;
  text-decoration: underline;
  text-decoration-style: dotted;
  text-decoration-color: var(--rule);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  letter-spacing: 0.02em;
  transition: color var(--dur-fast), text-decoration-color var(--dur-fast);
  font-family: var(--font-body);
}
.nav-links a:hover {
  color: var(--viridian);
  text-decoration-color: var(--viridian);
}
.nav-links a.current {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-style: solid;
  text-decoration-color: var(--viridian);
  text-decoration-thickness: 1.5px;
}

/* ── Hero — journal x lab ── */
.hero {
  padding: var(--space-5xl) 0 var(--space-3xl);
}
.hero-compact {
  padding: var(--space-3xl) 0 var(--space-2xl);
}
.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-3);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: var(--space-md);
}
.hero h1 {
  margin-bottom: var(--space-md);
}
.hero-subtitle {
  font-family: var(--font-body);
  font-size: clamp(16px, 2vw, 19px);
  color: var(--ink-2);
  line-height: 1.5;
  margin-bottom: var(--space-lg);
  max-width: 54ch;
}
.hero-meta {
  display: flex;
  gap: var(--space-xl);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-3);
  margin-top: var(--space-md);
  flex-wrap: wrap;
}
.hero-meta span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.hero-meta span::before {
  content: '';
  width: 4px;
  height: 4px;
  border-radius: 0;
  background: var(--viridian);
  opacity: 0.5;
}

/* ── Forms — underline-only, lab-notebook ── */
fieldset {
  border: 0;
  padding: 0;
  margin: 0 0 var(--space-xl);
}
legend {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 0 0 var(--space-md);
  border-bottom: 1px solid var(--rule);
  width: 100%;
  margin-bottom: var(--space-md);
}
.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg) var(--space-xl);
}
.field {
  display: flex;
  flex-direction: column;
}
.field-label {
  font-size: 12px;
  font-weight: 500;
  color: var(--ink-2);
  margin-bottom: var(--space-xs);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  font-family: var(--font-body);
}
.field-label a {
  font-size: 12px;
  text-transform: none;
  letter-spacing: 0;
  margin-left: 6px;
  font-weight: 400;
  text-decoration: underline dotted;
}

/* Underline inputs */
input[type="text"],
input[type="date"],
input[type="number"],
input[type="file"],
select {
  padding: 10px 0;
  font-size: 15px;
  border: none;
  border-bottom: 1px solid var(--rule);
  background: transparent;
  color: var(--ink);
  outline: none;
  border-radius: 0;
  transition: border-color var(--dur-fast);
  font-family: var(--font-body);
  width: 100%;
}
input:focus,
select:focus {
  border-bottom-color: var(--viridian);
}
input::placeholder { color: var(--ink-3); opacity: 0.5; }
select {
  -webkit-appearance: none;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg width='10' height='6' viewBox='0 0 10 6' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1l4 4 4-4' stroke='%2371717a' stroke-width='1.5' fill='none'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 4px center;
  padding-right: 20px;
}
select option { background: var(--canvas); color: var(--ink); }

/* Base Variant input — larger, mono */
#base_variant {
  font-family: var(--font-mono);
  font-size: 17px;
  letter-spacing: 0.02em;
}

/* Validation */
.invalid-feedback {
  color: var(--amber);
  font-size: 11px;
  margin-top: 4px;
  display: none;
  font-family: var(--font-mono);
}
.is-invalid {
  border-bottom-color: var(--amber) !important;
}

/* Field divider — thin rule + fork-node + mono label */
.field-divider {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin: var(--space-xl) 0 var(--space-md);
}
.field-divider::before {
  content: '';
  flex: 1;
  border-top: 1px solid var(--rule);
}
.field-divider::after {
  content: '';
  flex: 1;
  border-top: 1px solid var(--rule);
}
.field-divider .fd-label {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  flex-shrink: 0;
}

/* ── Buttons — solid viridian rectangle, 4px radius ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 36px;
  border: none;
  border-radius: 4px;
  background: var(--viridian);
  color: #fff;
  font-weight: 600;
  font-size: 15px;
  font-family: var(--font-body);
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: background var(--dur-fast) var(--ease);
}
.btn:hover {
  background: var(--ink);
}
.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}
.btn:disabled:hover { background: var(--viridian); }

.btn-outline {
  background: transparent;
  color: var(--viridian);
  border: 1px solid var(--viridian);
}
.btn-outline:hover {
  background: var(--viridian-10);
  color: var(--viridian);
}

.form-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding-top: var(--space-md);
}

/* ── Results — dark ink well (print pull-quote) ── */
#resultHeader {
  display: none;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--rule);
}
.results-grid {
  display: flex;
  flex-direction: column;
  gap: 0;
  background: var(--ink);
  padding: var(--space-xl);
}
.results-grid:empty { display: none; }
.result-card {
  display: flex;
  gap: var(--space-md);
  align-items: flex-start;
  padding: var(--space-sm) 0;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  animation: fadeIn 200ms var(--ease) forwards;
  opacity: 0;
}
.result-card:last-child {
  border-bottom: 0;
}
.result-badge {
  width: 24px;
  height: 24px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 500;
  font-size: 12px;
  color: var(--viridian);
  flex-shrink: 0;
  font-family: var(--font-mono);
  border: 1px solid var(--viridian);
  background: transparent;
}
.result-content {
  font-size: 13px;
  color: #e4e4e7;
  line-height: 1.7;
  font-family: var(--font-mono);
  word-break: break-all;
}
.result-content .dlogit {
  color: var(--amber);
  font-weight: 500;
  float: right;
  margin-left: var(--space-md);
}

/* ── Tables — minimal, zebra, mono header ── */
.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--rule);
}

/* ── Clade badge — mono, viridian text, no fill ── */
.clade-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--viridian);
  padding: 2px 0;
}

/* ── Variant code — mono ── */
.variant-code {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink);
}

/* ── Sequence name ── */
.seq-name {
  max-width: 300px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink);
}

/* ── Confidence bar — 2px hairline, viridian fill on rule track ── */
.conf-cell {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 110px;
}
.conf-bar {
  width: 64px;
  height: 2px;
  background: var(--rule);
  flex-shrink: 0;
}
.conf-fill {
  height: 100%;
  background: var(--viridian);
  transition: width 0.5s var(--ease);
}
.conf-text {
  font-size: 12px;
  font-weight: 500;
  color: var(--ink-2);
  font-family: var(--font-mono);
}

/* ── Mutation toggle — mono, viridian ── */
.mut-count {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  cursor: pointer;
  color: var(--viridian);
  font-weight: 500;
  user-select: none;
  font-size: 12px;
  font-family: var(--font-mono);
  transition: color var(--dur-fast);
}
.mut-count:hover { color: var(--ink); }
.mut-count .arrow {
  font-size: 8px;
  transition: transform var(--dur-fast);
}
.mut-count.expanded .arrow { transform: rotate(180deg); }
.mut-detail {
  margin-top: var(--space-sm);
  font-size: 12px;
  color: var(--ink-2);
  max-width: 380px;
  word-break: break-all;
  background: var(--canvas-2);
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-mono);
  line-height: 1.7;
}
.mut-detail-row {
  background: var(--canvas-2);
}

/* ── Recent Variants ── */
.recent-section {
  margin-bottom: var(--space-xl);
}
.recent-details {
  border: 1px solid var(--rule);
  padding: var(--space-md) var(--space-lg);
  background: var(--canvas);
}
.recent-details summary {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 15px;
  color: var(--ink);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}
.recent-count {
  color: var(--ink-3);
  font-family: var(--font-mono);
  font-size: 13px;
}
.recent-list {
  margin-top: var(--space-md);
  font-size: 13px;
  color: var(--ink-2);
}

/* ── Growth-tracking link (to cov-atlas trends) ── */
.growth-link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 18px;
  letter-spacing: -0.01em;
  color: var(--ink);
  text-decoration: underline dotted var(--rule);
  text-underline-offset: 5px;
  text-decoration-thickness: 1px;
  transition: color var(--dur-fast) var(--ease);
}
.growth-link:hover { color: var(--viridian); }
.growth-link .branch-tick svg { width: 14px; height: 16px; }
.growth-link .link-arrow { color: var(--viridian); margin-left: 2px; }
.recent-list table { width: 100%; border-collapse: collapse; font-size: 0.85em; }
.recent-list th {
  text-align: left;
  padding: 6px 10px;
  color: var(--ink-3);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  font-size: 10px;
  border-bottom: 1px solid var(--rule);
}
.recent-list td {
  padding: 6px 10px;
  border-top: 1px solid var(--rule);
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-2);
}

/* ── Batch Section ── */
.batch-section {
  margin-top: var(--space-2xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--rule);
}
.batch-section h3 {
  font-family: var(--font-display);
  font-size: 22px;
  margin: 0 0 6px;
  color: var(--ink);
  font-weight: 700;
}
.batch-section .sub {
  color: var(--ink-2);
  font-size: 15px;
  margin-bottom: var(--space-lg);
  line-height: 1.5;
  font-family: var(--font-body);
}
.batch-upload {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  flex-wrap: wrap;
}
.batch-upload input[type="file"] {
  flex: 1;
  min-width: 200px;
  font-size: 14px;
}
.batch-upload input[type="file"]::file-selector-button {
  background: var(--canvas-2);
  color: var(--ink);
  border: 1px solid var(--rule);
  padding: 6px 16px;
  font-family: var(--font-body);
  font-size: 13px;
  cursor: pointer;
  margin-right: 12px;
  border-radius: 2px;
  transition: background var(--dur-fast);
}
.batch-upload input[type="file"]::file-selector-button:hover {
  background: var(--rule);
}
.btn-batch {
  padding: 14px 32px;
  background: var(--viridian);
  color: #fff;
  border: none;
  border-radius: 4px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
  transition: background var(--dur-fast) var(--ease);
  font-family: var(--font-body);
  letter-spacing: 0.02em;
}
.btn-batch:hover { background: var(--ink); }
.btn-batch:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-batch:disabled:hover { background: var(--viridian); }
.batch-note {
  font-size: 12px;
  color: var(--ink-3);
  margin-top: var(--space-sm);
  font-family: var(--font-mono);
}
.batch-error {
  display: none;
  padding: var(--space-md);
  margin: var(--space-md) 0;
  background: var(--amber-10);
  border: 1px solid var(--amber-15);
  color: var(--amber);
  font-weight: 500;
  font-size: 14px;
}
.batch-results { display: none; margin-top: var(--space-lg); }
.batch-summary {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink-2);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--rule);
}
.batch-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}
.batch-table thead th {
  text-align: left;
  padding: 10px 14px;
  font-size: 11px;
  font-weight: 500;
  color: var(--ink-3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-bottom: 1px solid var(--ink-3);
}
.batch-table tbody td {
  padding: 10px 14px;
  border-bottom: 1px solid var(--rule);
  font-size: 13px;
  color: var(--ink-2);
}
.batch-table tbody tr:nth-child(even) td { background: var(--canvas-2); }
.batch-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--rule);
}
.pred-toggle {
  cursor: pointer;
  color: var(--viridian);
  font-weight: 500;
  user-select: none;
  font-size: 12px;
  font-family: var(--font-mono);
  transition: color var(--dur-fast);
}
.pred-toggle:hover { color: var(--ink); }
.pred-detail {
  display: none;
  margin-top: 4px;
  font-size: 12px;
  color: var(--ink-2);
  max-width: 340px;
  word-break: break-all;
  background: var(--canvas-2);
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-mono);
  line-height: 1.7;
}

/* ── Dropzone — dashed viridian border ── */
.drop-zone {
  border: 2px dashed var(--viridian);
  padding: 60px var(--space-xl);
  text-align: center;
  cursor: pointer;
  transition: all var(--dur) var(--ease);
  background: var(--canvas-2);
  margin-bottom: var(--space-lg);
  position: relative;
}
.drop-zone:hover {
  background: var(--viridian-10);
}
.drop-zone.dragover {
  border-style: solid;
  background: var(--viridian-10);
}
.drop-zone .dz-icon {
  margin-bottom: var(--space-md);
  display: flex;
  align-items: center;
  justify-content: center;
}
.drop-zone .dz-icon svg {
  width: 48px;
  height: 48px;
  color: var(--ink-3);
}
.drop-zone .hint {
  font-family: var(--font-display);
  font-size: 22px;
  color: var(--ink);
  margin-bottom: 6px;
  font-weight: 700;
}
.drop-zone .formats {
  font-size: 12px;
  color: var(--ink-3);
  font-family: var(--font-mono);
}

/* Branch grow indicator in dropzone dragover */
.drop-zone .dz-branch-grow {
  position: absolute;
  top: 12px;
  right: 16px;
  width: 28px;
  height: 20px;
  opacity: 0;
  transition: opacity var(--dur);
}
.drop-zone.dragover .dz-branch-grow {
  opacity: 1;
}
.drop-zone .dz-branch-grow svg line,
.drop-zone .dz-branch-grow svg path {
  stroke: var(--viridian);
  stroke-width: 1.4;
  stroke-linecap: round;
}

/* ── Classify: File Info ── */
.file-info {
  display: none;
  margin-bottom: var(--space-lg);
  padding: var(--space-md);
  background: var(--canvas-2);
  border: 1px solid var(--rule);
  font-size: 14px;
  color: var(--ink-2);
}
.file-info .file-name {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink);
}

/* ── Classify: Banners ── */
.error-banner {
  display: none;
  padding: var(--space-md);
  margin: var(--space-md) 0;
  background: var(--amber-10);
  border: 1px solid var(--amber-15);
  color: var(--amber);
  font-weight: 500;
  font-size: 14px;
}
.warning-banner {
  display: none;
  padding: var(--space-md);
  margin: var(--space-md) 0;
  background: var(--amber-10);
  border: 1px solid var(--amber-15);
  color: var(--amber);
  font-weight: 500;
  font-size: 14px;
}

/* ── Classify: Upload Actions ── */
.upload-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* ── Classify: Results ── */
.summary {
  display: none;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink-2);
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--rule);
}
.results-section { display: none; margin-top: var(--space-md); }

.result-table-wrap { overflow-x: auto; }
.result-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
  border: 1px solid var(--rule);
}
.result-table thead th {
  text-align: left;
  padding: 10px 14px;
  font-size: 11px;
  font-weight: 500;
  color: var(--ink-3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-bottom: 1px solid var(--ink-3);
}
.result-table tbody td {
  padding: 10px 14px;
  border-bottom: 1px solid var(--rule);
  vertical-align: top;
  color: var(--ink-2);
}
.result-table tbody tr:nth-child(even) td { background: var(--canvas-2); }
.result-table tbody tr {
  animation: fadeIn 0.3s var(--ease) forwards;
}

/* ── Tree page ── */
#tree {
  position: fixed;
  top: 57px;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--canvas);
}
#tree svg { display: block; }
#tree svg circle {
  stroke: var(--rule);
  stroke-width: 1.5;
  cursor: pointer;
  transition: stroke var(--dur-fast);
}
#tree svg circle:hover {
  stroke: var(--viridian);
  stroke-width: 2.5;
}
#tree svg text {
  font-size: 10px;
  font-family: var(--font-body);
}
#tree .link {
  fill: none;
  stroke: var(--rule);
  stroke-width: 1.4;
  stroke-opacity: 0.8;
  transition: stroke var(--dur-fast);
}
#tree .link:hover {
  stroke: var(--ink-3);
  stroke-opacity: 1;
}

/* Tree tooltip */
.tip {
  position: fixed;
  pointer-events: none;
  z-index: 200;
  background: var(--canvas);
  color: var(--ink);
  padding: 10px 14px;
  font-size: 12px;
  max-width: 300px;
  display: none;
  line-height: 1.5;
  border: 1px solid var(--rule);
}
.tip b { color: var(--ink); }

/* Tree search box */
.sbox {
  position: fixed;
  top: 70px;
  right: 20px;
  z-index: 10;
  background: var(--canvas);
  border: 1px solid var(--rule);
  padding: 6px 12px;
}
.sbox input {
  border: 0;
  outline: 0;
  font-size: 13px;
  width: 160px;
  background: transparent;
  color: var(--ink);
  font-family: var(--font-body);
}
.sbox input::placeholder { color: var(--ink-3); }

/* ── Footer — branch-seam top, 备案 ── */
.footer {
  padding: var(--space-xl) 0 var(--space-2xl);
  text-align: center;
  font-size: 11px;
  color: var(--ink-3);
  font-family: var(--font-body);
  border-top: 0;
  margin-top: var(--space-4xl);
  position: relative;
  z-index: 1;
}
.footer a {
  color: var(--ink-3);
  text-decoration: none;
  margin: 0 6px;
  transition: color var(--dur-fast);
}
.footer a:hover { color: var(--ink); }
.footer-mission {
  margin-bottom: 6px;
  font-family: var(--font-body);
}
.footer-beian {
  margin-bottom: 4px;
  font-family: var(--font-body);
}
.footer-stats {
  font-family: var(--font-mono);
}

/* ── Animations ── */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .navbar {
    padding: 12px var(--space-md);
  }
  .nav-links {
    gap: 16px;
  }
  .nav-links a {
    font-size: 11px;
  }
  .hero {
    padding: var(--space-3xl) 0 var(--space-2xl);
  }
  .hero-compact {
    padding: var(--space-2xl) 0 var(--space-xl);
  }
  .hero h1 {
    font-size: 36px;
  }
  .hero-subtitle {
    font-size: 15px;
  }
  .form-grid {
    grid-template-columns: 1fr;
  }
  .phylo-tree {
    margin: var(--space-xl) auto;
  }
  .footer {
    padding: var(--space-lg) 0 var(--space-xl);
  }
  .results-grid {
    padding: var(--space-md);
  }
  .result-table-wrap {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
  .result-table {
    min-width: 560px;
  }
  .drop-zone {
    padding: 40px var(--space-md);
  }
  .drop-zone .hint {
    font-size: 18px;
  }
  .upload-actions {
    flex-direction: column;
    align-items: stretch;
  }
  .batch-upload {
    flex-direction: column;
  }
  .batch-upload select,
  .batch-upload input[type="number"] {
    width: 100% !important;
  }
}

@media (max-width: 390px) {
  .hero {
    padding: var(--space-2xl) 0 var(--space-xl);
  }
  .hero h1 {
    font-size: 28px;
  }
  .hero-subtitle {
    font-size: 14px;
  }
  .section-header h2 {
    font-size: 22px;
  }
  .btn {
    padding: 12px 28px;
    font-size: 14px;
  }
  .navbar-wordmark {
    font-size: 16px;
  }
  .results-grid {
    padding: var(--space-md);
  }
}