:root {
  --bg: #f5f6f8;
  --surf-0: #ffffff;
  --surf-1: #f0f1f4;
  --surf-2: #e6e8ec;
  --surf-3: #d8dbe2;
  --border: #dfe2e8;
  --border-sub: #ebedf0;
  --accent: #2563eb;
  --accent-2: #1d4ed8;
  --accent-dim: rgba(37,99,235,.07);
  --accent-soft: rgba(37,99,235,.12);
  --cyan: #0891b2;
  --violet: #7c3aed;
  --text: #111827;
  --text-2: #4b5563;
  --text-3: #9ca3af;
  --text-4: #d0d4dc;
  --green: #16a34a;
  --red: #ef4444;
  --amber: #f59e0b;
  --font: 'Inter', system-ui, -apple-system, sans-serif;
  --mono: 'JetBrains Mono', ui-monospace, monospace;
}
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; background: var(--bg); color: var(--text);
  font-family: var(--font); -webkit-font-smoothing: antialiased; font-feature-settings: "ss01","cv11"; }
a { color: inherit; }
button { font: inherit; cursor: pointer; }

.shell { min-height: 100vh; display: flex; flex-direction: column; }

nav {
  display: flex; align-items: center; height: 56px;
  padding: 0 28px; border-bottom: 1px solid var(--border);
  background: rgba(255,255,255,.84); backdrop-filter: blur(12px);
  position: sticky; top: 0; z-index: 50;
}
.nav-brand { display: flex; align-items: baseline; gap: 3px;
  font-size: 18px; font-weight: 700; letter-spacing: -.02em;
  text-decoration: none; color: var(--text);
}
.nav-brand span { color: var(--accent); }
.nav-tag {
  margin-left: 14px; font-family: var(--mono); font-size: 10px;
  color: var(--text-3); letter-spacing: .06em; text-transform: uppercase;
  padding: 3px 8px; background: var(--surf-1); border-radius: 4px;
  border: 1px solid var(--border);
}
.nav-spacer { flex: 1; }
.nav-link {
  font-size: 13px; color: var(--text-2); text-decoration: none;
  padding: 6px 10px; border-radius: 6px; transition: background .15s, color .15s;
}
.nav-link:hover { background: var(--surf-1); color: var(--text); }

main { flex: 1; max-width: 1080px; margin: 0 auto; padding: 64px 28px 80px; width: 100%; }

.hero { margin-bottom: 56px; }
.hero h1 {
  font-size: clamp(36px, 5vw, 52px); font-weight: 800; letter-spacing: -.035em;
  line-height: 1.05; margin-bottom: 18px; color: var(--text); max-width: 760px;
}
.hero h1 .accent {
  background: linear-gradient(135deg, var(--accent), var(--cyan));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero p {
  font-size: 17px; line-height: 1.55; color: var(--text-2); max-width: 620px;
}

.actions {
  display: grid; grid-template-columns: 1fr 1fr; gap: 18px;
  margin-bottom: 12px;
}
.action {
  position: relative;
  background: var(--surf-0); border: 1px solid var(--border); border-radius: 18px;
  padding: 28px 28px 24px;
  cursor: pointer; transition: all .22s cubic-bezier(.4,.0,.2,1);
  overflow: hidden;
  text-align: left;
  display: flex; flex-direction: column; gap: 16px;
  min-height: 280px;
}
.action:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 16px 40px rgba(37,99,235,.12), 0 2px 4px rgba(0,0,0,.04);
}
.action::after {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(circle at top left, rgba(37,99,235,.06), transparent 50%);
  opacity: 0; transition: opacity .22s; pointer-events: none;
}
.action:hover::after { opacity: 1; }
.action[disabled] { cursor: not-allowed; opacity: .6; }
.action[disabled]:hover { transform: none; border-color: var(--border); box-shadow: 0 1px 3px rgba(0,0,0,.04); }
.action-icon {
  width: 48px; height: 48px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  background: var(--accent-dim); color: var(--accent);
  margin-bottom: 4px;
  transition: transform .22s;
}
.action.is-upload .action-icon { background: rgba(8,145,178,.08); color: var(--cyan); }
.action:hover .action-icon { transform: scale(1.05); }
.action-title { font-size: 19px; font-weight: 700; letter-spacing: -.015em; color: var(--text); }
.action-desc { font-size: 14px; color: var(--text-2); line-height: 1.5; flex: 1; }
.action-cta {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 13px; font-weight: 600; color: var(--accent);
  padding-top: 4px;
}
.action.is-upload .action-cta { color: var(--cyan); }
.action-cta svg { transition: transform .22s; }
.action:hover .action-cta svg { transform: translateX(3px); }

.action.dragging {
  border-color: var(--accent); background: var(--accent-dim);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.capability-row {
  display: flex; align-items: center; gap: 12px;
  margin: 22px 0 56px;
  font-size: 12px; color: var(--text-3); font-family: var(--mono); letter-spacing: .02em;
}
.cap-dot {
  width: 6px; height: 6px; border-radius: 50%; background: var(--text-4);
}
.cap-dot.on { background: var(--green); }

.section-hdr {
  display: flex; align-items: baseline; justify-content: space-between;
  margin: 0 0 18px;
}
.section-title {
  font-size: 12px; font-weight: 600; letter-spacing: .08em;
  text-transform: uppercase; color: var(--text-3);
}

.cards {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(420px, 1fr));
  gap: 14px; margin-bottom: 48px;
}
.card {
  display: block; text-decoration: none; color: inherit;
  background: var(--surf-0); border: 1px solid var(--border); border-radius: 14px;
  padding: 22px 24px; cursor: pointer; transition: all .22s;
  position: relative; overflow: hidden;
}
.card:hover { border-color: var(--accent); box-shadow: 0 8px 24px rgba(37,99,235,.08); transform: translateY(-1px); }
.card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--cyan));
  opacity: 0; transition: opacity .22s;
}
.card:hover::before { opacity: 1; }

.card-row { display: flex; align-items: center; justify-content: space-between; gap: 16px; margin-bottom: 6px; }
.card-tag {
  font-family: var(--mono); font-size: 10px; font-weight: 500;
  letter-spacing: .08em; text-transform: uppercase;
  padding: 3px 8px; border-radius: 5px; white-space: nowrap;
}
.card-tag.tag-local  { background: rgba(124,58,237,.08); color: var(--violet); border: 1px solid rgba(124,58,237,.18); }
.card-tag.tag-upload { background: rgba(8,145,178,.08); color: var(--cyan); border: 1px solid rgba(8,145,178,.18); }
.card-tag.tag-demo   { background: var(--surf-1); color: var(--text-3); border: 1px solid var(--border); }
.card-actions { display: flex; gap: 4px; }
.card-actions button {
  width: 26px; height: 26px; border-radius: 6px; border: none;
  background: transparent; color: var(--text-3);
  display: flex; align-items: center; justify-content: center;
}
.card-actions button:hover { background: var(--surf-1); color: var(--text-2); }

.card-title { font-size: 16px; font-weight: 700; letter-spacing: -.015em; margin: 4px 0 6px; color: var(--text); }
.card-subtitle { font-size: 13px; color: var(--text-2); }
.card-meta { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 14px; }
.meta-chip {
  display: inline-flex; align-items: center; gap: 5px;
  padding: 3px 10px; background: var(--surf-1); border: 1px solid var(--border-sub);
  border-radius: 16px; font-size: 11px; color: var(--text-2);
}
.meta-chip b { color: var(--text); font-weight: 600; }

.card-demo { padding: 26px 28px; }
.card-demo .card-title { font-size: 19px; }
.card-demo .badge-row { display: flex; gap: 8px; margin-top: 18px; }
.badge {
  display: inline-flex; align-items: center; gap: 5px;
  padding: 5px 11px; border-radius: 6px;
  font-size: 11px; font-weight: 600; letter-spacing: .015em;
}
.badge-ai {
  background: linear-gradient(135deg, rgba(124,58,237,.08), rgba(37,99,235,.08));
  border: 1px solid rgba(124,58,237,.2); color: var(--violet);
}
.badge-series { background: var(--surf-1); border: 1px solid var(--border-sub); color: var(--text-2); }

footer {
  padding: 28px; border-top: 1px solid var(--border);
  font-size: 11px; color: var(--text-3); text-align: center;
  font-family: var(--mono); letter-spacing: .03em;
  background: var(--surf-0);
}
footer .ft-row { max-width: 1080px; margin: 0 auto; display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 8px; }

/* Modal */
.modal-bg {
  position: fixed; inset: 0; background: rgba(15,18,25,.55); backdrop-filter: blur(8px);
  z-index: 100; display: none; align-items: center; justify-content: center;
  padding: 24px;
  animation: fadeIn .18s ease;
}
.modal-bg.open { display: flex; }
.modal {
  background: var(--surf-0); border-radius: 18px;
  width: 100%; max-width: 620px; max-height: calc(100vh - 48px);
  display: flex; flex-direction: column;
  box-shadow: 0 24px 64px rgba(0,0,0,.18), 0 4px 16px rgba(0,0,0,.08);
  overflow: hidden;
  animation: modalIn .22s cubic-bezier(.4,0,.2,1);
}
.modal-hdr {
  display: flex; align-items: center; justify-content: space-between;
  padding: 18px 24px; border-bottom: 1px solid var(--border-sub);
}
.modal-title { font-size: 15px; font-weight: 700; color: var(--text); letter-spacing: -.01em; }
.modal-close {
  width: 28px; height: 28px; border-radius: 50%; border: none; background: var(--surf-1);
  color: var(--text-3); display: flex; align-items: center; justify-content: center; font-size: 18px;
  line-height: 1; transition: all .15s;
}
.modal-close:hover { background: var(--surf-2); color: var(--text); }

.steps { display: flex; gap: 8px; padding: 16px 24px 0; align-items: center; }
.step-dot { display: flex; align-items: center; gap: 8px; font-size: 12px; color: var(--text-3); font-weight: 500; }
.step-dot .num {
  width: 22px; height: 22px; border-radius: 50%;
  background: var(--surf-1); color: var(--text-3); border: 1px solid var(--border);
  display: flex; align-items: center; justify-content: center; font-size: 11px; font-weight: 600;
  transition: all .22s;
}
.step-dot.active .num { background: var(--accent); color: #fff; border-color: var(--accent); }
.step-dot.done    .num { background: var(--green); color: #fff; border-color: var(--green); }
.step-dot.active, .step-dot.done { color: var(--text); }
.step-line { flex: 1; height: 1px; background: var(--border); }
.step-line.done { background: var(--green); }

.modal-body { padding: 22px 24px 24px; overflow-y: auto; }
.modal-foot {
  padding: 16px 24px; border-top: 1px solid var(--border-sub);
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
}

.btn {
  font-size: 13px; font-weight: 600; padding: 10px 16px; border-radius: 10px;
  border: 1px solid var(--border); background: var(--surf-0); color: var(--text);
  transition: all .15s;
}
.btn:hover { background: var(--surf-1); border-color: var(--text-4); }
.btn.primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.btn.primary:hover { background: var(--accent-2); border-color: var(--accent-2); box-shadow: 0 4px 14px rgba(37,99,235,.32); }
.btn.primary[disabled] { background: var(--text-4); border-color: var(--text-4); cursor: not-allowed; box-shadow: none; }
.btn.ghost { background: transparent; border: none; color: var(--text-2); }
.btn.ghost:hover { background: var(--surf-1); }

.picker-tabs { display: flex; padding: 4px; background: var(--surf-1); border-radius: 10px; margin-bottom: 16px; }
.picker-tab {
  flex: 1; padding: 8px 12px; border-radius: 7px; border: none; background: transparent;
  font-size: 13px; font-weight: 500; color: var(--text-2);
  transition: all .15s;
}
.picker-tab.active { background: var(--surf-0); color: var(--text); box-shadow: 0 1px 2px rgba(0,0,0,.06); }
.picker-tab[disabled] { opacity: .4; cursor: not-allowed; }

.dropzone {
  border: 2px dashed var(--border); border-radius: 14px;
  padding: 36px 24px; text-align: center;
  transition: all .15s; background: var(--surf-1);
}
.dropzone.is-drag { border-color: var(--accent); background: var(--accent-dim); }
.dropzone p { font-size: 14px; color: var(--text-2); margin-bottom: 14px; }
.dropzone p b { color: var(--text); font-weight: 600; }
.dropzone-hint { font-size: 11px; color: var(--text-3); margin-top: 12px; font-family: var(--mono); }

.privacy-line {
  display: flex; align-items: flex-start; gap: 8px;
  margin-top: 16px;
  font-size: 12px; color: var(--text-3); line-height: 1.5;
  padding: 12px 14px; background: var(--surf-1); border-radius: 10px;
}
.privacy-line.local svg { color: var(--green); }
.privacy-line.upload svg { color: var(--amber); }
.privacy-line svg { flex-shrink: 0; margin-top: 1px; }

.preview-section { margin-bottom: 18px; }
.preview-section h3 { font-size: 11px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--text-3); margin-bottom: 8px; }
.preview-table { width: 100%; border-collapse: collapse; font-size: 13px; }
.preview-table td { padding: 8px 0; border-bottom: 1px solid var(--border-sub); color: var(--text-2); }
.preview-table td:first-child { color: var(--text-3); width: 38%; font-size: 12px; }
.preview-table td b { color: var(--text); font-weight: 600; }

.preview-series { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 8px; }
.preview-series .pser {
  background: var(--surf-1); border: 1px solid var(--border-sub); border-radius: 8px;
  padding: 10px 12px;
}
.preview-series .pser-name { font-size: 12px; font-weight: 600; color: var(--text); margin-bottom: 2px; }
.preview-series .pser-meta { font-size: 11px; color: var(--text-3); font-family: var(--mono); }

.title-input {
  width: 100%; padding: 10px 14px; border: 1px solid var(--border); border-radius: 10px;
  font-size: 14px; font-family: var(--font); font-weight: 500; color: var(--text);
  background: var(--surf-0); transition: border-color .15s, box-shadow .15s;
}
.title-input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }

.progress-card { background: var(--surf-1); border-radius: 12px; padding: 18px 20px; }
.progress-row { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 8px; font-size: 13px; }
.progress-row b { font-weight: 600; color: var(--text); }
.progress-bar { height: 6px; background: var(--surf-2); border-radius: 4px; overflow: hidden; }
.progress-fill {
  height: 100%; background: linear-gradient(90deg, var(--accent), var(--cyan));
  transition: width .2s ease-out;
}
.progress-detail { font-size: 11px; color: var(--text-3); margin-top: 8px; font-family: var(--mono); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

.error-box {
  background: rgba(239,68,68,.06); border: 1px solid rgba(239,68,68,.2); border-radius: 10px;
  padding: 12px 14px; font-size: 13px; color: var(--red); margin-top: 12px;
}

@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes modalIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

@media (max-width: 720px) {
  .actions { grid-template-columns: 1fr; }
  main { padding: 40px 20px 60px; }
  .hero h1 { font-size: 34px; }
  .cards { grid-template-columns: 1fr; }
}