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

:root {
  --bg: #0b0b10;
  --surface: #14141e;
  --border: #252535;
  --accent: #22c55e;
  --accent-hover: #16a34a;
  --text: #e8e8f0;
  --muted: #7878a0;
  --success: #4ade80;
  --radius: 14px;
}

html { scroll-behavior: smooth; }
body { background: var(--bg); color: var(--text); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; font-size: 16px; line-height: 1.65; }
a { color: inherit; text-decoration: none; }

/* ── NAV ─────────────────────────────────────────────────────── */
.navbar { position: sticky; top: 0; z-index: 100; display: flex; align-items: center; justify-content: space-between; padding: 0 40px; height: 60px; background: rgba(11,11,16,0.88); backdrop-filter: blur(12px); border-bottom: 1px solid var(--border); }
.nav-logo { font-size: 1.15rem; font-weight: 800; color: var(--text); }
.nav-logo span { color: var(--accent); }

/* ── HERO ────────────────────────────────────────────────────── */
.hero { padding: 100px 20px 80px; text-align: center; position: relative; overflow: hidden; }
.hero::before { content: ''; position: absolute; top: -200px; left: 50%; transform: translateX(-50%); width: 800px; height: 600px; background: radial-gradient(ellipse, rgba(34,197,94,0.13) 0%, transparent 70%); pointer-events: none; }
.hero-inner { position: relative; max-width: 760px; margin: 0 auto; }
.hero-badge { display: inline-block; background: rgba(34,197,94,0.12); border: 1px solid rgba(34,197,94,0.3); color: #86efac; font-size: 0.8rem; font-weight: 600; padding: 4px 14px; border-radius: 20px; margin-bottom: 24px; letter-spacing: 0.04em; text-transform: uppercase; }
h1 { font-size: clamp(2rem, 5vw, 3.2rem); font-weight: 800; line-height: 1.15; letter-spacing: -0.02em; margin-bottom: 20px; }
.gradient-text { background: linear-gradient(135deg, #22c55e, #86efac); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero-sub { font-size: 1.1rem; color: var(--muted); max-width: 580px; margin: 0 auto 32px; }
.hero-sub strong { color: var(--text); }
.hero-cta { display: flex; flex-direction: column; align-items: center; gap: 10px; margin-bottom: 48px; }
.hero-note { font-size: 0.8rem; color: var(--muted); }
.hero-stats { display: flex; align-items: center; justify-content: center; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px 32px; }
.hstat { display: flex; flex-direction: column; align-items: center; padding: 0 28px; }
.hstat strong { font-size: 1.6rem; font-weight: 800; background: linear-gradient(135deg, #22c55e, #86efac); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hstat span { font-size: 0.78rem; color: var(--muted); margin-top: 2px; }
.hstat-div { width: 1px; height: 36px; background: var(--border); }

/* ── SECTIONS ────────────────────────────────────────────────── */
.section-inner { max-width: 1000px; margin: 0 auto; padding: 0 20px; }
.section-inner--narrow { max-width: 720px; }
.section-title { font-size: clamp(1.4rem, 3vw, 1.9rem); font-weight: 800; text-align: center; margin-bottom: 48px; letter-spacing: -0.02em; }

/* ── FEATURES ────────────────────────────────────────────────── */
.features { padding: 80px 20px; border-top: 1px solid var(--border); }
.features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; }
.feature-card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 28px; transition: border-color 0.2s, transform 0.2s; }
.feature-card:hover { border-color: rgba(34,197,94,0.35); transform: translateY(-2px); }
.feat-icon { font-size: 1.8rem; margin-bottom: 14px; }
.feature-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: 8px; }
.feature-card p { font-size: 0.88rem; color: var(--muted); line-height: 1.6; }

/* ── TOOL ────────────────────────────────────────────────────── */
.tool-section { padding: 80px 20px; border-top: 1px solid var(--border); background: var(--surface); }

.mode-tabs { display: flex; gap: 8px; margin-bottom: 28px; background: var(--bg); border: 1px solid var(--border); border-radius: 12px; padding: 6px; width: fit-content; }
.mode-tab { padding: 9px 22px; border-radius: 8px; border: none; background: transparent; color: var(--muted); font-size: 0.9rem; font-weight: 600; cursor: pointer; transition: background 0.15s, color 0.15s; }
.mode-tab.active { background: var(--accent); color: #0b0b10; }

.mode-panel { display: none; }
.mode-panel.active { display: block; }

/* Drop zone */
.drop-zone { border: 2px dashed var(--border); border-radius: var(--radius); padding: 56px 24px; text-align: center; cursor: pointer; transition: border-color 0.2s, background 0.2s; }
.drop-zone:hover, .drop-zone.drag-over { border-color: var(--accent); background: rgba(34,197,94,0.04); }
.drop-icon { font-size: 3rem; margin-bottom: 16px; }
.drop-title { font-size: 1.05rem; font-weight: 600; margin-bottom: 6px; }
.drop-sub { font-size: 0.88rem; color: var(--muted); }

/* File info */
.file-info { background: var(--bg); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px 20px; margin-top: 16px; }
.file-meta { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.file-name { font-size: 0.9rem; font-weight: 600; color: var(--accent); word-break: break-all; }
.sheet-selector-wrap { display: flex; align-items: center; gap: 10px; margin-top: 12px; font-size: 0.88rem; color: var(--muted); }
.sheet-select { background: var(--surface); border: 1px solid var(--border); color: var(--text); border-radius: 8px; padding: 6px 10px; font-size: 0.88rem; outline: none; cursor: pointer; }
.sheet-select:focus { border-color: rgba(34,197,94,0.4); }

/* Preview */
.preview-wrap { margin-top: 20px; }
.preview-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; flex-wrap: wrap; gap: 10px; }
.preview-label { font-size: 0.82rem; font-weight: 600; color: var(--muted); text-transform: uppercase; letter-spacing: 0.05em; }
.table-scroll { overflow-x: auto; border: 1px solid var(--border); border-radius: 10px; }
.preview-table { width: 100%; border-collapse: collapse; font-size: 0.82rem; }
.preview-table th { background: rgba(34,197,94,0.08); color: var(--accent); font-weight: 700; padding: 10px 14px; text-align: left; border-bottom: 1px solid var(--border); white-space: nowrap; }
.preview-table td { padding: 9px 14px; border-bottom: 1px solid var(--border); color: var(--muted); white-space: nowrap; max-width: 200px; overflow: hidden; text-overflow: ellipsis; }
.preview-table tr:last-child td { border-bottom: none; }
.preview-table tr:hover td { background: rgba(34,197,94,0.03); color: var(--text); }

/* ── HOW IT WORKS ─────────────────────────────────────────────── */
.how-section { padding: 80px 20px; border-top: 1px solid var(--border); }
.steps-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 24px; }
.step { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 32px 24px; text-align: center; }
.step-num { width: 48px; height: 48px; border-radius: 50%; background: rgba(34,197,94,0.12); border: 1px solid rgba(34,197,94,0.3); color: var(--accent); font-size: 1.2rem; font-weight: 800; display: flex; align-items: center; justify-content: center; margin: 0 auto 18px; }
.step h3 { font-size: 1rem; font-weight: 700; margin-bottom: 10px; }
.step p { font-size: 0.88rem; color: var(--muted); line-height: 1.65; }

/* ── FAQ ─────────────────────────────────────────────────────── */
.faq-section { padding: 80px 20px; border-top: 1px solid var(--border); }
.faq-list { display: flex; flex-direction: column; gap: 12px; }
.faq-item { background: var(--surface); border: 1px solid var(--border); border-radius: 10px; overflow: hidden; }
.faq-item summary { padding: 18px 20px; font-weight: 600; font-size: 0.95rem; cursor: pointer; list-style: none; display: flex; justify-content: space-between; align-items: center; user-select: none; }
.faq-item summary::after { content: '+'; font-size: 1.2rem; color: var(--accent); transition: transform 0.2s; }
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p { padding: 0 20px 18px; font-size: 0.9rem; color: var(--muted); line-height: 1.7; }

/* ── BUTTONS ─────────────────────────────────────────────────── */
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 11px 22px; border-radius: 9px; font-size: 0.9rem; font-weight: 600; cursor: pointer; border: none; transition: background 0.15s, transform 0.1s; white-space: nowrap; }
.btn:active { transform: scale(0.97); }
.btn-primary { background: var(--accent); color: #0b0b10; }
.btn-primary:hover { background: var(--accent-hover); }
.btn-lg { padding: 14px 32px; font-size: 1rem; border-radius: 10px; }
.btn-ghost { background: transparent; color: var(--muted); border: 1px solid var(--border); }
.btn-ghost:hover { color: var(--text); border-color: var(--text); }
.btn-sm { padding: 6px 14px; font-size: 0.8rem; }

/* ── TOAST ───────────────────────────────────────────────────── */
.toast { position: fixed; bottom: 28px; left: 50%; transform: translateX(-50%) translateY(20px); background: #1e1e2e; border: 1px solid var(--border); color: var(--text); font-size: 0.88rem; font-weight: 500; padding: 10px 20px; border-radius: 30px; opacity: 0; transition: opacity 0.2s, transform 0.2s; pointer-events: none; z-index: 999; }
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

/* ── FOOTER ──────────────────────────────────────────────────── */
.site-footer { border-top: 1px solid var(--border); background: var(--surface); }
.footer-inner { max-width: 1000px; margin: 0 auto; padding: 60px 20px 40px; display: flex; gap: 60px; flex-wrap: wrap; }
.footer-brand { flex: 2; min-width: 220px; }
.footer-brand p { color: var(--muted); font-size: 0.88rem; margin-top: 10px; line-height: 1.7; }
.footer-home-link { display: inline-flex; align-items: center; gap: 6px; margin-top: 14px; font-size: 0.85rem; font-weight: 600; color: var(--accent); border: 1px solid var(--border); padding: 7px 14px; border-radius: 8px; transition: background 0.15s, color 0.15s; }
.footer-home-link:hover { background: var(--surface); border-color: var(--accent); color: var(--text); }
.footer-links { flex: 1; min-width: 120px; }
.footer-links h3 { font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); margin-bottom: 14px; }
.footer-links ul { list-style: none; display: flex; flex-direction: column; gap: 8px; }
.footer-links a { font-size: 0.88rem; color: var(--muted); transition: color 0.15s; }
.footer-links a:hover { color: var(--text); }
.footer-bottom { border-top: 1px solid var(--border); text-align: center; padding: 20px; font-size: 0.8rem; color: var(--muted); } .footer-bottom a { color: var(--muted); text-decoration: underline; text-underline-offset: 3px; transition: color 0.15s; } .footer-bottom a:hover { color: var(--text); }

/* ── RESPONSIVE ──────────────────────────────────────────────── */
@media (max-width: 640px) {
  .navbar { padding: 0 20px; }
  .hero { padding: 70px 16px 60px; }
  .hero-stats { padding: 16px; flex-wrap: wrap; }
  .hstat { padding: 0 12px; }
  .hstat-div { display: none; }
  .mode-tabs { width: 100%; }
  .mode-tab { flex: 1; text-align: center; }
  .footer-inner { gap: 32px; }
}