/* JT-GELFLOW landing site
   Apache 2.0 — Jason Cheng (Jason Tools)
   Self-contained: no external CDNs / fonts. */

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

:root {
  --bg:        #0a0e14;
  --bg-elev:   #11161e;
  --surface:   #161c26;
  --border:    #1f2937;
  --text:      #e6edf3;
  --text-dim:  #b4c0cf;                /* was #9ba8b8 — bumped a notch for readability on dark bg */
  --accent:    #00d4ff;
  --accent-2:  #00ff88;
  --warn:      #ff9f43;
  --danger:    #ff6b6b;
  --max-w:     1100px;
  --radius:    10px;
  --shadow-1:  0 0 0 1px rgba(255,255,255,.05),
               0 1px 2px rgba(0,0,0,.3),
               0 8px 20px rgba(0,0,0,.25);
  --shadow-2:  0 0 0 1px rgba(255,255,255,.08),
               0 1px 2px rgba(0,0,0,.15),
               0 8px 20px rgba(0,0,0,.20),
               0 32px 64px -8px rgba(0,0,0,.25);
}

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue",
               "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", Arial, sans-serif;
  background: radial-gradient(ellipse at top, #11202a 0%, var(--bg) 60%) fixed;
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

code, pre { font-family: ui-monospace, SFMono-Regular, "JetBrains Mono", Menlo, Consolas, monospace; }

/* ───────── Top nav ───────── */
.nav {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 28px;
  background: rgba(10, 14, 20, 0.78);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav .brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 600; font-size: 16px; letter-spacing: 0.5px;
  color: var(--text);
  white-space: nowrap;
  flex-shrink: 0;
}
.nav .brand .logo-dot {
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--accent-2);
  box-shadow: 0 0 12px var(--accent-2);
  animation: breathe 2s ease-in-out infinite;
}
@keyframes breathe {
  0%, 100% { opacity: 0.6; box-shadow: 0 0 4px var(--accent-2); }
  50%      { opacity: 1;   box-shadow: 0 0 14px var(--accent-2); }
}
.nav .links { display: flex; gap: 18px; align-items: center; font-size: 14px; }
.nav .links a { color: var(--text-dim); white-space: nowrap; flex-shrink: 0; }
.nav .links a:hover { color: var(--accent); text-decoration: none; }
.nav .lang {
  padding: 4px 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 13px;
  white-space: nowrap;
  flex-shrink: 0;
}

/* Hamburger toggle — desktop hides it, narrow viewports show it. */
.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 6px;
  width: 38px;
  height: 38px;
  padding: 0;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 4px;
}
.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--text);
  border-radius: 1px;
  transition: transform 0.2s, opacity 0.2s;
}
.nav.open .nav-toggle span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav.open .nav-toggle span:nth-child(2) { opacity: 0; }
.nav.open .nav-toggle span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* Narrow viewports: collapse the link strip into a dropdown drawer
   triggered by the hamburger button. */
@media (max-width: 720px) {
  .nav { padding: 12px 16px; }
  .nav-toggle { display: flex; }
  .nav .links {
    position: absolute;
    top: 100%;
    right: 16px;
    left: 16px;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 0;
    background: rgba(10, 14, 20, 0.96);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border);
    border-radius: 10px;
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.4);
    font-size: 15px;
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.18s ease, opacity 0.18s ease;
  }
  .nav.open .links {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
  .nav .links a {
    padding: 12px 18px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  }
  .nav .links a:last-child { border-bottom: none; }
  .nav .lang {
    margin: 8px 12px 4px;
    text-align: center;
  }
}

/* ───────── Hero ───────── */
.hero {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 80px 28px 50px;
  text-align: center;
}
.hero h1 {
  font-size: clamp(38px, 6vw, 64px);
  font-weight: 700;
  letter-spacing: -1px;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-2) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 16px;
}
.hero .tagline {
  font-size: clamp(17px, 2.2vw, 22px);
  color: var(--text-dim);
  max-width: 760px;
  margin: 0 auto 14px;
}
.hero .promise {
  font-size: 14px;
  color: var(--text-dim);
  margin-bottom: 32px;
}
.hero .promise strong { color: var(--text); }
.hero .ctas { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; margin-top: 22px; }

.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 22px;
  border-radius: 8px;
  font-size: 15px; font-weight: 500;
  border: 1px solid transparent;
  transition: transform 0.15s, box-shadow 0.15s, border-color 0.15s;
  cursor: pointer;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent) 0%, #00a8d4 100%);
  color: #04121a;
  box-shadow: 0 4px 14px rgba(0,212,255,0.25);
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 6px 20px rgba(0,212,255,0.35); text-decoration: none; }
.btn-ghost {
  background: transparent;
  color: var(--text);
  border-color: var(--border);
}
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }

/* ───────── Install block ───────── */
.install {
  max-width: 820px;
  margin: 30px auto 0;
  padding: 0 28px;
}
.install .tabs {
  display: flex; gap: 4px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 0;
}
.install .tab {
  background: transparent; border: 0; color: var(--text-dim);
  padding: 10px 16px;
  font-size: 13px; cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
}
.install .tab.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}
/* Wrap the <pre> so the copy button can position relative to a non-scrolling
   parent. Without this, scrolling the pre horizontally would drag the button
   along with the code text. */
.install .code-block { position: relative; }
.install .code-block[hidden] { display: none; }
.install .prereq-note {
  margin: 14px 0 12px;
  padding: 12px 16px;
  background: rgba(0, 212, 255, 0.05);
  border: 1px dashed var(--border);
  border-radius: var(--radius);
  font-size: 13.5px;
  color: var(--text);                     /* full brightness — this is body copy you actually need to read */
  line-height: 1.7;
}
.install .prereq-note code.kbd { font-size: 12.5px; }
.install .prereq-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13.5px;
  margin-bottom: 12px;
  margin-top: -6px;
}
.install .prereq-table td {
  padding: 8px 14px;
  border-top: 1px solid var(--border);
  vertical-align: middle;
  color: var(--text);
}
.install .prereq-table tr:first-child td { border-top: 0; }
.install .prereq-table td:first-child {
  white-space: nowrap;
  width: 1%;
  font-weight: 500;                       /* distro family labels read at full text colour */
}
.install .prereq-table code.kbd { font-size: 12.5px; }

.install .install-followup {
  margin-top: 18px;
  padding: 14px 16px;
  background: rgba(0, 212, 255, 0.06);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--text-dim);
}
.install .install-followup strong { color: var(--text); }
.install .install-followup em { font-style: normal; color: var(--text); }
.install .install-followup a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px dashed currentColor;
}
.install pre {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-top: 0;
  border-radius: 0 0 var(--radius) var(--radius);
  padding: 18px 20px;
  overflow-x: auto;
  font-size: 14px;
  margin: 0;
}
.install pre code { color: var(--text); }
.install .code-block .copy-btn {
  position: absolute; top: 12px; right: 12px; z-index: 2;
  background: var(--surface);
  color: var(--text-dim);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 4px 10px;
  font-size: 12px;
  cursor: pointer;
}
.install .code-block .copy-btn:hover { color: var(--accent); }
.install .post-note {
  display: grid;
  grid-template-columns: max-content 1fr;
  column-gap: 16px;
  row-gap: 8px;
  margin: 22px auto 0;
  max-width: max-content;
  color: var(--text-dim);
  font-size: 13px;
  align-items: center;
}
.install .post-note dt {
  color: var(--text-dim);
  font-weight: 500;
  font-size: 11px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  text-align: right;
}
.install .post-note dd {
  margin: 0;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}
.install .post-note .muted {
  color: var(--text-dim);
  font-size: 12.5px;
  opacity: 1;                             /* dim alone is enough; piling 0.85 on top made it unreadable */
}
@media (max-width: 600px) {
  .install .post-note {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .install .post-note dt { text-align: center; }
  .install .post-note dd { justify-content: center; }
}

/* ───────── Sections ───────── */
section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 70px 28px;
}
section h2 {
  font-size: clamp(26px, 3vw, 34px);
  font-weight: 600;
  margin-bottom: 8px;
}
section .subhead {
  color: var(--text-dim);
  margin-bottom: 36px;
  font-size: 16px;
}

/* Four view modes — 2×2 grid (cyan / mint / coral / purple). Stacks at <640px. */
.modes {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}
@media (max-width: 640px) {
  .modes { grid-template-columns: 1fr; }
}
.mode {
  --mode-accent: var(--accent);
  --mode-accent-soft: rgba(0,212,255,0.12);
  --mode-glow: rgba(0,212,255,0.18);
  background:
    linear-gradient(180deg, var(--mode-accent-soft) 0%, transparent 60%),
    var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px 22px;
  position: relative;
  overflow: hidden;
  transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s;
}
/* Coloured top stripe + glow */
.mode::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--mode-accent);
  opacity: 0.85;
}
.mode:hover {
  transform: translateY(-3px);
  border-color: var(--mode-accent);
  box-shadow:
    0 12px 28px rgba(0,0,0,0.35),
    0 0 0 1px var(--mode-glow);
}
.mode .icon {
  width: 38px; height: 38px;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--mode-accent-soft);
  border-radius: 8px;
  color: var(--mode-accent);
  margin-bottom: 14px;
}
.mode h3 {
  font-size: 18px;
  margin-bottom: 8px;
  color: var(--mode-accent);
}
.mode p { color: var(--text-dim); font-size: 14px; }

/* Per-card accents */
.mode:nth-child(1) {
  --mode-accent: #00d4ff;          /* Flow — cyan */
  --mode-accent-soft: rgba(0,212,255,0.10);
  --mode-glow: rgba(0,212,255,0.22);
}
.mode:nth-child(2) {
  --mode-accent: #00ff88;          /* 2D Map — mint */
  --mode-accent-soft: rgba(0,255,136,0.10);
  --mode-glow: rgba(0,255,136,0.22);
}
.mode:nth-child(3) {
  --mode-accent: #ff9f43;          /* 3D Globe — coral/orange */
  --mode-accent-soft: rgba(255,159,67,0.12);
  --mode-glow: rgba(255,159,67,0.22);
}
.mode:nth-child(4) {
  --mode-accent: #c56cf0;          /* Sankey — purple */
  --mode-accent-soft: rgba(197,108,240,0.12);
  --mode-glow: rgba(197,108,240,0.22);
}

/* Video player */
.video-wrap {
  max-width: 1080px;
  margin: 0 auto;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow:
    0 0 0 1px rgba(255,255,255,.08),
    0 1px 2px rgba(0,0,0,.15),
    0 8px 20px rgba(0,0,0,.20),
    0 32px 64px -8px rgba(0,0,0,.25);
}
.video-wrap video {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;            /* lock the box before metadata loads — no layout shift on click-to-play */
  height: auto;
  background: #000;
}

/* Click-to-load facade — keeps the demo video off the wire on first paint.
   Aspect ratio matches the recording (16:9-ish); no fake screenshot poster
   so there's no frame mismatch when the real video starts. */
.video-facade {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 14px;
  width: 100%;
  aspect-ratio: 16 / 9;
  border: 0;
  cursor: pointer;
  color: #e6edf3;
  background:
    /* dark scrim so the play button + label stay readable on top of the frame */
    linear-gradient(180deg, rgba(5,7,9,0.45) 0%, rgba(5,7,9,0.65) 100%),
    url("screenshots/demo_poster.jpg") center / cover no-repeat;
  transition: filter 0.2s;
}
.video-facade:hover { filter: brightness(1.15); }
.video-facade-play {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 84px;
  height: 84px;
  border-radius: 50%;
  background: rgba(0, 212, 255, 0.92);
  color: #061015;
  box-shadow: 0 0 24px rgba(0,212,255,0.45);
  transition: transform 0.2s, box-shadow 0.2s;
}
.video-facade:hover .video-facade-play {
  transform: scale(1.05);
  box-shadow: 0 0 32px rgba(0,212,255,0.65);
}
.video-facade-label {
  font-size: 14px;
  letter-spacing: 0.5px;
  color: var(--text-dim);
}

/* Feature grid — 3x3 on desktop (9 cards), 2 cols on tablet, 1 col on mobile. */
.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
@media (max-width: 900px) {
  .features { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 560px) {
  .features { grid-template-columns: 1fr; }
}
.feature {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.feature h4 {
  font-size: 15px;
  margin-bottom: 6px;
  display: flex; align-items: center; gap: 8px;
}
.feature h4::before {
  content: "";
  width: 6px; height: 6px;
  background: var(--accent);
  border-radius: 50%;
  flex-shrink: 0;
}
.feature p { color: var(--text-dim); font-size: 13.5px; }

/* Screenshots */
.shots {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}
.shot {
  background: var(--surface);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  display: block;
  color: inherit;
  text-decoration: none;
  padding: 12px 12px 0;             /* inner gap so image isn't flush with card border */
  transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s;
}
.shot:hover {
  text-decoration: none;
  transform: translateY(-3px);
  border-color: rgba(0,212,255,0.4);
  box-shadow: 0 12px 28px rgba(0,0,0,0.3);
}
.shot .ss-img {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, #1a2a35 0%, #0d1219 100%);
  display: flex; align-items: center; justify-content: center;
  color: var(--text-dim);
  font-size: 13px;
  letter-spacing: 0.5px;
  position: relative;
  border-radius: 6px;               /* matches inner inset */
}
.shot img.ss-img {
  background: none;
  display: block;
  height: auto;
  object-fit: cover;
  image-rendering: auto;             /* explicit bilinear for downscaled thumbs */
  transform: translateZ(0);          /* nudge GPU compositor — smooths Chrome/Safari downscaling */
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
}
.shot .label {
  padding: 12px 6px 14px;
  font-size: 14px;
}
.shot .label small { color: var(--text-dim); display: block; margin-top: 2px; font-size: 12px; }
.placeholder-tag {
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  padding: 6px 14px;
  border: 1px dashed var(--border);
  border-radius: 6px;
  background: rgba(0,0,0,0.3);
  font-size: 12px;
  letter-spacing: 1px;
  text-transform: uppercase;
}

/* Footer */
footer {
  border-top: 1px solid var(--border);
  margin-top: 60px;
  padding: 32px 28px;
  text-align: center;
  color: var(--text-dim);
  font-size: 13.5px;
}
footer a { color: var(--text-dim); }
footer a:hover { color: var(--accent); }
footer .row { display: flex; gap: 18px; justify-content: center; flex-wrap: wrap; margin-bottom: 8px; }

/* Tiny utilities */
.kbd {
  display: inline-block;
  padding: 2px 8px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 4px;
  font-family: ui-monospace, monospace;
  font-size: 12px;
}

/* Field mapping cards */
.mapping-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}
.mapping-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 20px;
}
.mapping-card h4 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--accent);
}
.mapping-card p {
  font-size: 13.5px;
  line-height: 1.6;
  margin-bottom: 8px;
  color: var(--text-dim);
}
.mapping-card p:last-child { margin-bottom: 0; }
.mapping-card .muted-line {
  font-size: 12px;
  opacity: 0.85;
}
.mapping-card code.kbd { font-size: 11.5px; }
.mapping-cta {
  margin-top: 24px;
  text-align: center;
  font-size: 14px;
  color: var(--text-dim);
}
.mapping-cta a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px dashed currentColor;
}

/* Hotkeys grid */
.hotkeys {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}
.hk {
  display: flex;
  align-items: center;
  gap: 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
}
.hk-keys {
  display: flex;
  gap: 4px;
  flex-shrink: 0;
}
.hk-keys .kbd {
  font-size: 13px;
  padding: 4px 10px;
  min-width: 28px;
  text-align: center;
}
.hk-desc {
  font-size: 14px;
  color: var(--text-dim);
}

/* ─── Lightbox ─────────────────────────────────────────────────────────── */
.shot {
  /* override default <button> chrome — but keep the inset padding from the
     original .shot rule above so the screenshot doesn't hit the card edge. */
  font: inherit;
  width: 100%;
  text-align: left;
  margin: 0;
}
.shot:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 1000;
  background: rgba(0, 0, 0, 0.92);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  cursor: zoom-out;
  animation: lightbox-fade 0.2s ease-out;
}
@keyframes lightbox-fade {
  from { opacity: 0; }
  to   { opacity: 1; }
}
.lightbox[hidden] { display: none; }
.lightbox-img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  border-radius: 6px;
  box-shadow:
    0 0 0 1px rgba(255,255,255,0.06),
    0 24px 80px rgba(0,0,0,0.8);
  animation: lightbox-zoom 0.2s ease-out;
}
@keyframes lightbox-zoom {
  from { transform: scale(0.96); opacity: 0; }
  to   { transform: scale(1);    opacity: 1; }
}
.lightbox-close {
  position: absolute;
  top: 16px;
  right: 20px;
  width: 40px;
  height: 40px;
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 50%;
  font-size: 26px;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s, transform 0.15s;
}
.lightbox-close:hover {
  background: rgba(255, 255, 255, 0.18);
  transform: scale(1.05);
}

/* ─── Promise chips (hero) ─────────────────────────────────────────────── */
.promise-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin: 24px 0 8px;
}
.promise-chips .chip {
  display: inline-flex;
  align-items: center;
  padding: 5px 12px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.3px;
  border: 1px solid;
  background: rgba(0, 0, 0, 0.2);
  white-space: nowrap;
}
.chip-cyan   { color: #00d4ff; border-color: rgba(0,212,255,0.4);   background: rgba(0,212,255,0.08);  }
.chip-mint   { color: #00ff88; border-color: rgba(0,255,136,0.4);   background: rgba(0,255,136,0.08);  }
.chip-purple { color: #c56cf0; border-color: rgba(197,108,240,0.4); background: rgba(197,108,240,0.08); }
.chip-coral  { color: #ff9f43; border-color: rgba(255,159,67,0.4);  background: rgba(255,159,67,0.08);  }
.chip-amber  { color: #ffd93d; border-color: rgba(255,217,61,0.4);  background: rgba(255,217,61,0.08);  }