:root {
  --bg: #06080d;
  --surface: rgba(14, 18, 27, 0.92);
  --surface-2: rgba(19, 24, 36, 0.92);
  --line: rgba(130, 160, 210, 0.18);
  --text: #f5f7fb;
  --muted: #9aa5b7;
  --accent: #67c9ff;
  --accent-2: #39e0c1;
  --contact-border: rgba(103, 201, 255, 0.26);
  --contact-bg: transparent;
  --page-shadow: 0 14px 40px rgba(0, 0, 0, 0.24);
  --field-bg: rgba(19, 24, 36, 0.88);
  --video-bg: linear-gradient(135deg, rgba(103, 201, 255, 0.1), rgba(57, 224, 193, 0.06));
}

:root[data-theme="light"] {
  --bg: #eef3f8;
  --surface: rgba(255, 255, 255, 0.94);
  --surface-2: rgba(244, 247, 251, 0.98);
  --line: rgba(73, 104, 145, 0.18);
  --text: #182230;
  --muted: #5d6b7f;
  --accent: #176fcb;
  --accent-2: #008d78;
  --contact-border: rgba(23, 111, 203, 0.18);
  --contact-bg: rgba(23, 111, 203, 0.05);
  --page-shadow: 0 12px 28px rgba(50, 74, 110, 0.1);
  --field-bg: rgba(244, 247, 251, 0.98);
  --video-bg: linear-gradient(135deg, rgba(23, 111, 203, 0.08), rgba(0, 141, 120, 0.06));
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: Inter, "Segoe UI", Arial, sans-serif;
  background:
    radial-gradient(circle at top left, rgba(57, 224, 193, 0.08), transparent 25%),
    radial-gradient(circle at top right, rgba(103, 201, 255, 0.1), transparent 25%),
    var(--bg);
  color: var(--text);
  line-height: 1.5;
}

button,
input,
textarea {
  font: inherit;
}

.page-shell {
  width: min(1380px, 95%);
  margin: 0 auto;
  padding: 1rem 0 2rem;
}

.masthead,
.browser-panel,
.inspector-panel,
.about,
.contact {
  border: 1px solid var(--line);
  background: var(--surface);
  backdrop-filter: blur(12px);
  box-shadow: var(--page-shadow);
}

.masthead {
  display: flex;
  justify-content: space-between;
  align-items: end;
  border-radius: 20px;
  padding: 1rem 1.1rem;
  margin-bottom: 1rem;
}

.masthead-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.brand {
  margin: 0;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.tagline {
  margin: 0.15rem 0 0;
  color: var(--muted);
}

.contact-link {
  color: var(--accent);
  text-decoration: none;
  border: 1px solid var(--contact-border);
  border-radius: 999px;
  padding: 0.45rem 0.8rem;
  background: var(--contact-bg);
}

.theme-toggle {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.45rem 0.8rem;
  background: var(--surface-2);
  color: var(--text);
  cursor: pointer;
}

.workspace {
  display: grid;
  grid-template-columns: minmax(360px, 420px) 1fr;
  gap: 1rem;
}

.browser-panel,
.inspector-panel {
  border-radius: 22px;
}

.section-head {
  padding: 1.1rem;
  border-bottom: 1px solid var(--line);
}

.section-head h1,
.inspector-panel h2,
.about h2,
.contact h2 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
}

.section-head p,
.about p,
.form-note,
.empty-state,
.browser-status,
.browser-error,
.task-description,
.meta-list li span {
  margin: 0;
  color: var(--muted);
}

.environment-stack,
.session-stack,
.task-stack,
.meta-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.environment-card,
.session-card {
  border-bottom: 1px solid var(--line);
}

.environment-trigger,
.session-trigger,
.task-trigger {
  width: 100%;
  border: 0;
  background: transparent;
  color: var(--text);
  text-align: left;
  cursor: pointer;
}

.environment-trigger,
.session-trigger {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 1rem;
  align-items: center;
  padding: 1rem 1.1rem;
}

.environment-trigger strong,
.session-trigger strong,
.task-trigger strong {
  display: block;
  font-size: 0.96rem;
  font-weight: 600;
}

.environment-trigger span,
.session-trigger span {
  display: block;
  font-size: 0.82rem;
  color: var(--muted);
  margin-top: 0.18rem;
}

.badge {
  color: var(--accent-2);
  font-size: 0.78rem;
  border: 1px solid rgba(57, 224, 193, 0.24);
  border-radius: 999px;
  padding: 0.32rem 0.55rem;
}

.animated-panel {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 220ms ease;
}

.animated-panel.is-open {
  grid-template-rows: 1fr;
}

.animated-inner {
  overflow: hidden;
}

.session-stack {
  padding: 0 0.75rem 0.8rem;
}

.session-card {
  margin-top: 0.75rem;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--surface-2);
  overflow: hidden;
}

.task-stack {
  padding: 0 0.85rem 0.75rem;
}

.task-trigger {
  border-top: 1px solid var(--line);
  padding: 0.85rem 0;
  transition: transform 180ms ease, color 180ms ease;
}

.task-trigger:hover,
.task-trigger.is-selected {
  transform: translateX(6px);
}

.task-trigger.is-selected strong {
  color: var(--accent);
}

.inspector-panel {
  padding: 1rem;
  position: sticky;
  top: 1rem;
  height: fit-content;
}

.task-card {
  display: grid;
  gap: 1rem;
  animation: fade-in 220ms ease;
}

.task-top {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: start;
}

.route {
  color: var(--muted);
  font-size: 0.82rem;
  margin: 0 0 0.35rem;
}

.marker {
  color: var(--accent);
  border: 1px solid rgba(103, 201, 255, 0.24);
  border-radius: 999px;
  padding: 0.35rem 0.6rem;
  font-size: 0.8rem;
}

.video-frame {
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line);
  border-radius: 18px;
  overflow: hidden;
  background: var(--video-bg);
  position: relative;
  display: grid;
  grid-template-rows: minmax(0, 1fr) auto;
}

.video-stage,
.video-thumbnail,
.video-frame video,
.video-empty {
  width: 100%;
  height: 100%;
}

.video-stage {
  position: relative;
  overflow: hidden;
  background: #000;
}

.video-frame video {
  display: block;
  object-fit: contain;
  background: #000;
}

.video-thumbnail {
  display: block;
  object-fit: contain;
  background: #000;
  z-index: 1;
}

.video-controls {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto auto auto;
  align-items: center;
  gap: 0.65rem;
  padding: 0.65rem 0.8rem;
  border-top: 1px solid var(--line);
  background: var(--surface-2);
}

.video-control-button {
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  color: var(--text);
  padding: 0.35rem 0.7rem;
  cursor: pointer;
}

.video-progress,
.video-volume {
  width: 100%;
  accent-color: var(--accent);
}

.video-volume {
  max-width: 90px;
}

.video-time {
  color: var(--muted);
  font-size: 0.8rem;
  white-space: nowrap;
}

.video-empty {
  display: grid;
  place-items: center;
  padding: 1rem;
  text-align: center;
  color: var(--muted);
}

.meta-list {
  display: grid;
  gap: 0.7rem;
}

.meta-list li {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  border-top: 1px solid var(--line);
  padding-top: 0.7rem;
}

.meta-list li strong {
  font-size: 0.82rem;
}

.support-grid {
  display: grid;
  grid-template-columns: minmax(360px, 420px) 1fr;
  gap: 1rem;
  margin-top: 1rem;
}

.about,
.contact {
  border-radius: 18px;
  padding: 1rem 1.1rem;
}

.contact-form {
  display: grid;
  gap: 0.8rem;
  max-width: 100%;
}

.contact-form label {
  display: block;
}

.contact-form input,
.contact-form textarea,
.contact-form button {
  border-radius: 14px;
  border: 1px solid var(--line);
  background: var(--field-bg);
  color: var(--text);
  padding: 0.75rem 0.85rem;
}

.contact-form button {
  width: fit-content;
  cursor: pointer;
}

.browser-status,
.browser-error {
  padding: 1rem 1.1rem;
  border-top: 1px solid var(--line);
}

.browser-error {
  color: #d96c7a;
}

.environment-trigger:focus-visible,
.session-trigger:focus-visible,
.task-trigger:focus-visible,
.theme-toggle:focus-visible,
.contact-link:focus-visible,
.video-control-button:focus-visible,
.contact-form button:focus-visible,
input:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

@keyframes fade-in {
  from {
    opacity: 0;
    transform: translateY(6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 1120px) {
  .workspace {
    grid-template-columns: 1fr;
  }

  .support-grid {
    grid-template-columns: 1fr;
  }

  .inspector-panel {
    position: static;
  }
}

@media (max-width: 640px) {
  .masthead,
  .masthead-actions,
  .task-top,
  .meta-list li {
    flex-direction: column;
    align-items: start;
  }

  .video-controls {
    grid-template-columns: 1fr;
  }
}