/* ═══════════════════════════════════════════════
   StructureXplorer — Dark Molecular Theme
   Fonts: Syne (display) · DM Sans (body) · JetBrains Mono (code)
═══════════════════════════════════════════════ */

/* ── CSS Variables ─────────────────────────── */
:root {
  --bg:          #070b14;
  --surface:     #0d1526;
  --surface-2:   #131f35;
  --surface-3:   #192843;
  --border:      #1c2f4a;
  --border-2:    #243d60;

  --accent:      #00e5b8;
  --accent-dim:  #00b894;
  --accent-glow: rgba(0, 229, 184, 0.15);
  --purple:      #7c4dff;
  --purple-dim:  rgba(124, 77, 255, 0.12);

  --text:        #d0dcf0;
  --text-dim:    #607a9c;
  --text-muted:  #3d5470;

  --danger:      #ff4d6d;
  --success:     #00e5b8;
  --warning:     #ffc147;

  --radius:      10px;
  --radius-sm:   6px;
  --radius-lg:   16px;

  --font-display: 'Syne', sans-serif;
  --font-body:    'DM Sans', sans-serif;
  --font-mono:    'JetBrains Mono', monospace;

  --nav-h: 60px;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.6;
  min-height: 100vh;
  /* dot-grid background */
  background-image:
    radial-gradient(circle at 1px 1px, rgba(255,255,255,0.04) 1px, transparent 0);
  background-size: 28px 28px;
}

/* ── Nav ────────────────────────────────────── */
.nav {
  position: sticky; top: 0; z-index: 100;
  height: var(--nav-h);
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 2rem;
  background: rgba(7, 11, 20, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-brand {
  display: flex; align-items: center; gap: 0.6rem;
  text-decoration: none; color: var(--text);
}
.nav-icon { font-size: 1.4rem; color: var(--accent); }
.nav-title { font-family: var(--font-display); font-weight: 700; font-size: 1.1rem; letter-spacing: -0.02em; }

.nav-links { display: flex; align-items: center; gap: 1.6rem; }
.nav-link {
  color: var(--text-dim); font-size: 0.9rem; text-decoration: none;
  transition: color 0.2s;
}
.nav-link:hover { color: var(--accent); }
.nav-link--ext { color: var(--accent-dim); font-size: 0.85rem; }

/* ── Main ───────────────────────────────────── */
.main { max-width: 1280px; margin: 0 auto; padding: 2.5rem 2rem 4rem; }

/* ── Footer ─────────────────────────────────── */
.footer {
  text-align: center;
  padding: 1.2rem;
  font-size: 0.78rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
}
.footer-sep { margin: 0 0.5rem; }

/* ── Utility ────────────────────────────────── */
.hidden  { display: none !important; }
.mono    { font-family: var(--font-mono); font-size: 0.82rem; }

/* ── Hero ───────────────────────────────────── */
.hero {
  position: relative;
  padding: 5rem 0 3.5rem;
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 70% 40%, rgba(0,229,184,0.06) 0%, transparent 70%),
    radial-gradient(ellipse 40% 60% at 20% 60%, rgba(124,77,255,0.06) 0%, transparent 70%);
  pointer-events: none;
}
.hero-inner { position: relative; }

.hero-badge {
  display: inline-block;
  padding: 0.3rem 0.9rem;
  border: 1px solid var(--accent);
  border-radius: 999px;
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--accent);
  letter-spacing: 0.05em;
  margin-bottom: 1.5rem;
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 6vw, 4.5rem);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.03em;
  color: var(--text);
  margin-bottom: 1.2rem;
}
.hero-accent { color: var(--accent); }

.hero-sub {
  max-width: 560px;
  color: var(--text-dim);
  font-size: 1.05rem;
  line-height: 1.65;
  margin-bottom: 3rem;
}

/* Steps */
.steps {
  display: flex; align-items: flex-start; gap: 0.8rem; flex-wrap: wrap;
}
.step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.2rem 1.4rem;
  flex: 1; min-width: 180px;
}
.step-num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  margin-bottom: 0.4rem;
  letter-spacing: 0.1em;
}
.step-label {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  margin-bottom: 0.3rem;
}
.step-desc  { font-size: 0.82rem; color: var(--text-dim); }
.step-arrow { color: var(--text-muted); font-size: 1.4rem; padding-top: 1.4rem; }

/* ── Cards ──────────────────────────────────── */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem;
}
.card-title {
  font-family: var(--font-display);
  font-size: 1.4rem; font-weight: 700;
  margin-bottom: 0.4rem;
}
.card-sub { color: var(--text-dim); font-size: 0.9rem; margin-bottom: 1.6rem; }

/* ── Upload Section ─────────────────────────── */
.upload-section { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; margin-top: 2rem; }
@media (max-width: 900px) { .upload-section { grid-template-columns: 1fr; } }

.upload-card { grid-column: 1; }

/* Drop zone */
.dropzone {
  position: relative;
  border: 2px dashed var(--border-2);
  border-radius: var(--radius);
  padding: 2.5rem;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s;
  margin-bottom: 1.4rem;
}
.dropzone:hover, .dropzone.dragover {
  border-color: var(--accent);
  background: var(--accent-glow);
}
.dropzone.has-file { border-color: var(--accent); background: var(--accent-glow); }
.dropzone-icon    { font-size: 2rem; margin-bottom: 0.6rem; color: var(--text-dim); }
.dropzone-text    { font-size: 0.95rem; color: var(--text-dim); margin-bottom: 0.3rem; }
.dropzone-link    { color: var(--accent); text-decoration: underline; }
.dropzone-hint    { font-size: 0.78rem; color: var(--text-muted); }
.dropzone-input   { position: absolute; inset: 0; opacity: 0; cursor: pointer; width: 100%; height: 100%; }

/* Format block */
.format-block { margin-bottom: 1.6rem; }
.format-label {
  font-family: var(--font-mono); font-size: 0.72rem;
  color: var(--text-muted); letter-spacing: 0.08em;
  text-transform: uppercase; margin-bottom: 0.5rem;
}
.code-block {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.9rem 1rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent);
  line-height: 1.7;
  overflow-x: auto;
}

.upload-actions { display: flex; justify-content: flex-end; }

.upload-result {
  margin-top: 1rem;
  padding: 0.8rem 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
}
.upload-result--success { background: rgba(0,229,184,0.08); border: 1px solid var(--accent); color: var(--accent); }
.upload-result--error   { background: rgba(255,77,109,0.08); border: 1px solid var(--danger);  color: var(--danger); }

/* Info grid */
.info-grid { display: flex; flex-direction: column; gap: 1rem; }
.info-card {
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.2rem;
  display: flex; align-items: flex-start; gap: 1rem;
}
.info-icon    { font-size: 1.4rem; flex-shrink: 0; }
.info-title   { font-weight: 600; font-size: 0.9rem; margin-bottom: 0.2rem; }
.info-text    { font-size: 0.82rem; color: var(--text-dim); line-height: 1.5; }

/* ── Buttons ────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.65rem 1.4rem;
  border: none; border-radius: var(--radius-sm);
  font-family: var(--font-body); font-size: 0.9rem; font-weight: 600;
  cursor: pointer; transition: all 0.18s;
}
.btn:disabled { opacity: 0.4; cursor: not-allowed; }
.btn--primary {
  background: var(--accent); color: #000;
}
.btn--primary:hover:not(:disabled) { background: #00ffcd; transform: translateY(-1px); box-shadow: 0 4px 20px rgba(0,229,184,0.3); }
.btn--ghost {
  background: transparent; color: var(--accent);
  border: 1px solid var(--border-2);
}
.btn--ghost:hover:not(:disabled) { border-color: var(--accent); }
.btn--sm  { padding: 0.38rem 0.85rem; font-size: 0.8rem; }
.btn--xs  { padding: 0.25rem 0.65rem; font-size: 0.75rem; }
.btn--predict {
  background: var(--purple-dim); color: var(--purple);
  border: 1px solid rgba(124,77,255,0.25);
}
.btn--predict:hover:not(:disabled) { background: rgba(124,77,255,0.2); border-color: var(--purple); }

.btn-loader { font-style: italic; color: inherit; }

/* ── Explore Layout ─────────────────────────── */
.explore-header {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 1.6rem; flex-wrap: wrap; gap: 1rem;
}
.explore-title { font-family: var(--font-display); font-size: 1.6rem; font-weight: 700; }
.explore-sub   { color: var(--text-dim); font-size: 0.88rem; margin-top: 0.2rem; }

/* Prediction meter */
.prediction-meter { display: flex; align-items: center; gap: 0.8rem; }
.pm-label { font-size: 0.78rem; color: var(--text-dim); font-family: var(--font-mono); letter-spacing: 0.04em; }
.pm-bar   { display: flex; gap: 0.4rem; }
.pm-pip   {
  width: 28px; height: 8px; border-radius: 4px;
  background: var(--surface-3);
  border: 1px solid var(--border-2);
  transition: background 0.3s;
}
.pm-pip--used { background: var(--accent); border-color: var(--accent); }
.pm-count { font-family: var(--font-mono); font-size: 0.9rem; }
.pm-used  { color: var(--accent); font-weight: 700; }
.pm-sep   { color: var(--text-muted); }
.pm-max   { color: var(--text-dim); }

/* Demo banner */
.demo-banner {
  background: rgba(255,193,71,0.08);
  border: 1px solid rgba(255,193,71,0.3);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  font-size: 0.85rem;
  color: var(--warning);
  margin-bottom: 1.4rem;
}
.demo-banner code {
  font-family: var(--font-mono); font-size: 0.8rem;
  background: rgba(255,193,71,0.1); padding: 0.1rem 0.3rem;
  border-radius: 3px;
}

.explore-layout {
  display: grid;
  grid-template-columns: 1fr 420px;
  gap: 1.5rem;
  align-items: start;
}
@media (max-width: 1100px) { .explore-layout { grid-template-columns: 1fr; } }

.panel { display: flex; flex-direction: column; gap: 1.2rem; }

/* ── Target selector ────────────────────────── */
.target-selector {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.2rem;
}

.field-label {
  display: block;
  font-family: var(--font-mono); font-size: 0.72rem;
  color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.08em;
  margin-bottom: 0.6rem;
}

.select {
  width: 100%;
  background: var(--bg);
  border: 1px solid var(--border-2);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.85rem;
  color: var(--text);
  font-family: var(--font-body); font-size: 0.9rem;
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%23607a9c' stroke-width='1.5' fill='none'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.9rem center;
  padding-right: 2.2rem;
}
.select:focus { outline: none; border-color: var(--accent); }

.target-meta {
  margin-top: 0.7rem;
  padding: 0.6rem 0.8rem;
  background: var(--surface-3);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--accent);
  font-size: 0.82rem;
  display: flex; flex-direction: column; gap: 0.15rem;
}
.tm-desc   { color: var(--text); }
.tm-cancer { color: var(--text-dim); font-size: 0.78rem; }

/* ── Metabolite table ────────────────────────── */
.metabolite-section {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.2rem;
}

.table-scroll { overflow-x: auto; margin-top: 0.5rem; }

.meta-table {
  width: 100%; border-collapse: collapse; font-size: 0.83rem;
}
.meta-table th {
  font-family: var(--font-mono); font-size: 0.7rem;
  text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--text-muted);
  padding: 0.5rem 0.7rem;
  border-bottom: 1px solid var(--border);
  text-align: left; white-space: nowrap;
}
.meta-table td {
  padding: 0.55rem 0.7rem;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}
.meta-row:hover td { background: var(--surface-2); }
.meta-row--failed td { opacity: 0.5; }

.cell-name   { font-weight: 500; white-space: nowrap; }
.cell-formula { color: var(--accent); }
.cell-smiles  { max-width: 180px; }

.smiles-pill {
  display: inline-block;
  font-family: var(--font-mono); font-size: 0.72rem;
  background: var(--surface-3); color: var(--text-dim);
  padding: 0.15rem 0.4rem; border-radius: 4px;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
  max-width: 160px; vertical-align: middle;
}
.smiles-fail {
  color: var(--danger); font-size: 0.78rem;
}

/* ── Right panel: viewer ────────────────────── */
.panel--right {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.4rem;
  position: sticky; top: calc(var(--nav-h) + 1.5rem);
}

.viewer-header {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 1rem;
}

.plddt-badge {
  font-family: var(--font-mono); font-size: 0.78rem;
  padding: 0.25rem 0.6rem;
  background: var(--surface-3); border: 1px solid var(--border-2);
  border-radius: 999px; color: var(--accent);
  display: flex; align-items: center; gap: 0.4rem;
}

/* Placeholder */
.viewer-placeholder {
  height: 340px;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 0.5rem;
  background: var(--bg);
  border: 1px dashed var(--border-2);
  border-radius: var(--radius);
}
.vp-icon { font-size: 3rem; color: var(--border-2); }
.vp-text { font-size: 0.95rem; color: var(--text-dim); }
.vp-hint { font-size: 0.78rem; color: var(--text-muted); }

/* 3Dmol container */
.viewer-container { position: relative; }
.mol-viewer {
  width: 100%; height: 340px;
  background: var(--bg);
  border-radius: var(--radius);
  overflow: hidden;
}

.viewer-controls {
  display: flex; gap: 0.4rem; margin-top: 0.6rem;
  justify-content: flex-end;
}
.vctrl-btn {
  background: var(--surface-2); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 0.3rem 0.65rem;
  color: var(--text-dim); cursor: pointer; font-size: 1rem;
  transition: all 0.15s;
}
.vctrl-btn:hover { border-color: var(--accent); color: var(--accent); }

/* Loading */
.viewer-loading {
  height: 340px;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 0.6rem;
  background: var(--bg); border-radius: var(--radius);
  border: 1px solid var(--border);
}
@keyframes spin { to { transform: rotate(360deg); } }
.spinner {
  width: 36px; height: 36px;
  border: 3px solid var(--border-2);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.9s linear infinite;
}
.loading-text { font-family: var(--font-display); font-weight: 600; font-size: 0.95rem; }
.loading-sub  { font-size: 0.78rem; color: var(--text-dim); }

/* Prediction info */
.pred-info {
  margin-top: 0.8rem;
  background: var(--surface-3);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.8rem;
}
.pi-row   { display: flex; justify-content: space-between; padding: 0.2rem 0; font-size: 0.83rem; }
.pi-label { color: var(--text-dim); }
.pi-val   { font-weight: 500; }

/* Confidence colors */
.conf-tag { padding: 0.1rem 0.4rem; border-radius: 4px; font-size: 0.72rem; font-weight: 600; }
.conf--high { background: rgba(0,229,184,0.15); color: var(--accent); }
.conf--med  { background: rgba(255,193,71,0.15); color: var(--warning); }
.conf--low  { background: rgba(255,77,109,0.15); color: var(--danger); }

.demo-tag {
  background: rgba(255,193,71,0.12);
  color: var(--warning); font-size: 0.72rem;
  padding: 0.1rem 0.4rem; border-radius: 4px;
}

/* Previous results */
.prev-results { margin-top: 1rem; }
.prev-card {
  background: var(--bg); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 0.7rem 0.9rem;
  margin-top: 0.5rem;
  display: flex; align-items: center; justify-content: space-between;
  gap: 0.5rem;
}
.prev-card-title { font-size: 0.83rem; font-weight: 500; flex: 1; }
.prev-card-meta  { font-size: 0.75rem; color: var(--text-dim); font-family: var(--font-mono); }

/* ── Empty state ────────────────────────────── */
.empty-state {
  text-align: center; padding: 5rem 2rem;
  display: flex; flex-direction: column; align-items: center; gap: 1rem;
}
.empty-icon { font-size: 4rem; color: var(--border-2); }
.empty-state h2 { font-family: var(--font-display); font-size: 1.8rem; }
.empty-state p  { color: var(--text-dim); }

/* ── Scrollbar ──────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border-2); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-dim); }

/* ════════════════════════════════════════════════
   Additions: Fix button · Export · Modal
════════════════════════════════════════════════ */

/* Fix SMILES button */
.btn--fix {
  background: rgba(255, 193, 71, 0.1);
  color: var(--warning);
  border: 1px solid rgba(255, 193, 71, 0.25);
}
.btn--fix:hover:not(:disabled) {
  background: rgba(255, 193, 71, 0.2);
  border-color: var(--warning);
}

/* Previous results header row */
.prev-results-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.4rem;
}

/* Previous card body + actions layout */
.prev-card-body    { flex: 1; min-width: 0; }
.prev-card-actions { display: flex; gap: 0.3rem; flex-shrink: 0; }

/* Text input (SMILES entry) */
.text-input {
  width: 100%;
  background: var(--bg);
  border: 1px solid var(--border-2);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.85rem;
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  margin-top: 0.4rem;
  transition: border-color 0.2s;
}
.text-input:focus {
  outline: none;
  border-color: var(--accent);
}
.text-input::placeholder { color: var(--text-muted); }

/* Accent link */
.link-accent { color: var(--accent); text-decoration: underline; }
.link-accent:hover { color: #00ffcd; }

/* ── Modal ───────────────────────────────────── */
.modal-overlay {
  position: fixed; inset: 0; z-index: 200;
  background: rgba(4, 8, 16, 0.82);
  backdrop-filter: blur(6px);
  display: flex; align-items: center; justify-content: center;
  padding: 1rem;
}

.modal-box {
  background: var(--surface);
  border: 1px solid var(--border-2);
  border-radius: var(--radius-lg);
  width: 100%; max-width: 480px;
  box-shadow: 0 24px 64px rgba(0,0,0,0.6);
  animation: modal-in 0.18s ease;
}

@keyframes modal-in {
  from { opacity: 0; transform: scale(0.96) translateY(8px); }
  to   { opacity: 1; transform: scale(1)    translateY(0);   }
}

.modal-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 1.2rem 1.4rem 0.8rem;
  border-bottom: 1px solid var(--border);
}
.modal-title {
  font-family: var(--font-display);
  font-size: 1.1rem; font-weight: 700;
}
.modal-close {
  background: none; border: none; color: var(--text-dim);
  font-size: 1rem; cursor: pointer; padding: 0.2rem 0.4rem;
  border-radius: 4px; transition: color 0.15s, background 0.15s;
}
.modal-close:hover { color: var(--text); background: var(--surface-3); }

.modal-body {
  padding: 1.2rem 1.4rem;
}
.modal-desc {
  font-size: 0.88rem; color: var(--text-dim);
  margin-bottom: 1rem; line-height: 1.55;
}
.modal-desc strong { color: var(--text); }

.modal-hint {
  margin-top: 0.6rem;
  font-size: 0.78rem; color: var(--text-muted);
  line-height: 1.5;
}

.modal-error {
  margin-top: 0.7rem;
  padding: 0.5rem 0.8rem;
  background: rgba(255, 77, 109, 0.08);
  border: 1px solid var(--danger);
  border-radius: var(--radius-sm);
  color: var(--danger);
  font-size: 0.82rem;
}

.modal-footer {
  display: flex; justify-content: flex-end; gap: 0.6rem;
  padding: 0.9rem 1.4rem 1.2rem;
  border-top: 1px solid var(--border);
}