:root {
  --bg: #f6f7f9;
  --panel: #ffffff;
  --panel-soft: #eef3f0;
  --text: #17201b;
  --muted: #64706a;
  --line: #dce3df;
  --primary: #146c5b;
  --primary-dark: #0e4d41;
  --accent: #b25531;
  --danger: #b3261e;
  --shadow: 0 16px 42px rgba(23, 32, 27, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
}

button,
input,
select,
textarea {
  font: inherit;
}

button {
  border: 0;
  cursor: pointer;
}

.app-shell {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
}

.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  padding: 28px 20px;
  background: #18231f;
  color: #f8faf9;
  overflow-y: auto;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 28px;
}

.brand-mark {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 8px;
  background: #d6efe6;
  color: #0d5547;
  font-weight: 800;
}

.brand h1 {
  margin: 0;
  font-size: 20px;
  line-height: 1.2;
}

.brand p {
  margin: 3px 0 0;
  color: #a9b7b1;
  font-size: 13px;
}

.group-list {
  display: grid;
  gap: 8px;
}

.group-button {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 12px 13px;
  border-radius: 8px;
  background: transparent;
  color: #d8e0dc;
  text-align: left;
}

.group-button:hover,
.group-button.active {
  background: rgba(255, 255, 255, 0.1);
  color: #ffffff;
}

.group-count {
  min-width: 26px;
  padding: 2px 8px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.12);
  color: #d6efe6;
  text-align: center;
  font-size: 12px;
}

.main {
  min-width: 0;
  padding: 32px;
}

.topbar {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 24px;
}

.topbar h2 {
  margin: 0;
  font-size: 28px;
  line-height: 1.2;
}

.topbar p {
  margin: 8px 0 0;
  color: var(--muted);
}

.search-wrap {
  min-width: 280px;
}

.input,
.select,
.textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
  color: var(--text);
  outline: none;
}

.input,
.select {
  height: 42px;
  padding: 0 12px;
}

.textarea {
  min-height: 86px;
  resize: vertical;
  padding: 10px 12px;
}

.input:focus,
.select:focus,
.textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(20, 108, 91, 0.12);
}

.video-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(320px, 0.8fr);
  gap: 22px;
  align-items: start;
}

.player-panel,
.list-panel,
.admin-panel,
.login-panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.player-panel {
  overflow: hidden;
}

.player-frame {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #0d1210;
}

.player-frame video {
  width: 100%;
  height: 100%;
  display: block;
  background: #0d1210;
}

.player-info {
  padding: 18px 20px 20px;
}

.player-info h3 {
  margin: 0;
  font-size: 22px;
  line-height: 1.25;
}

.player-info p {
  margin: 10px 0 0;
  color: var(--muted);
  line-height: 1.6;
}

.list-panel {
  padding: 14px;
}

.video-list {
  display: grid;
  gap: 10px;
  max-height: calc(100vh - 150px);
  overflow-y: auto;
  padding-right: 2px;
}

.video-item {
  width: 100%;
  display: grid;
  gap: 6px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
  color: var(--text);
  text-align: left;
}

.video-item:hover,
.video-item.active {
  border-color: rgba(20, 108, 91, 0.55);
  background: #f2f8f5;
}

.video-item strong {
  font-size: 15px;
  line-height: 1.35;
}

.video-item span {
  color: var(--muted);
  font-size: 13px;
}

.empty {
  padding: 48px 20px;
  border: 1px dashed var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.7);
  color: var(--muted);
  text-align: center;
}

.admin-shell {
  min-height: 100vh;
  padding: 28px;
}

.admin-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin: 0 auto 22px;
  max-width: 1180px;
}

.admin-header h1 {
  margin: 0;
  font-size: 28px;
}

.admin-header p {
  margin: 6px 0 0;
  color: var(--muted);
}

.admin-grid {
  max-width: 1180px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(320px, 0.7fr) minmax(0, 1.3fr);
  gap: 20px;
  align-items: start;
}

.admin-panel {
  padding: 20px;
}

.admin-panel h2 {
  margin: 0 0 16px;
  font-size: 19px;
}

.form-stack {
  display: grid;
  gap: 12px;
}

.field {
  display: grid;
  gap: 7px;
}

.field label {
  color: var(--muted);
  font-size: 13px;
}

.button-row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.btn {
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  padding: 0 14px;
  border-radius: 8px;
  background: var(--primary);
  color: #ffffff;
  font-weight: 700;
}

.btn:hover {
  background: var(--primary-dark);
}

.btn.secondary {
  border: 1px solid var(--line);
  background: #ffffff;
  color: var(--text);
}

.btn.secondary:hover {
  background: #f1f4f2;
}

.btn.danger {
  background: var(--danger);
}

.btn.danger:hover {
  background: #8f1e19;
}

.btn:disabled {
  cursor: not-allowed;
  opacity: 0.62;
}

.message {
  min-height: 22px;
  color: var(--muted);
  font-size: 14px;
}

.message.error {
  color: var(--danger);
}

.login-screen {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.login-panel {
  width: min(420px, 100%);
  padding: 26px;
}

.login-panel h1 {
  margin: 0 0 8px;
  font-size: 25px;
}

.login-panel p {
  margin: 0 0 18px;
  color: var(--muted);
}

.admin-list {
  display: grid;
  gap: 10px;
}

.admin-item {
  display: grid;
  gap: 10px;
  padding: 13px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.admin-item-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
}

.admin-item strong {
  line-height: 1.35;
}

.admin-item small {
  display: block;
  margin-top: 4px;
  color: var(--muted);
}

.admin-item-actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.small-btn {
  min-height: 32px;
  padding: 0 10px;
  border-radius: 8px;
  background: var(--panel-soft);
  color: var(--text);
  font-size: 13px;
}

.small-btn:hover {
  background: #dceae3;
}

.small-btn.danger {
  background: #fdebea;
  color: var(--danger);
}

.progress {
  width: 100%;
  height: 8px;
  overflow: hidden;
  border-radius: 999px;
  background: #e4ebe7;
}

.progress-bar {
  width: 0%;
  height: 100%;
  background: var(--accent);
  transition: width 0.2s ease;
}

.hidden {
  display: none !important;
}

@media (max-width: 980px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: relative;
    height: auto;
    padding: 18px;
  }

  .group-list {
    grid-auto-flow: column;
    grid-auto-columns: minmax(150px, max-content);
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .video-layout,
  .admin-grid {
    grid-template-columns: 1fr;
  }

  .video-list {
    max-height: none;
  }
}

@media (max-width: 680px) {
  .main,
  .admin-shell {
    padding: 18px;
  }

  .topbar,
  .admin-header {
    display: grid;
  }

  .search-wrap {
    min-width: 0;
  }

  .topbar h2,
  .admin-header h1 {
    font-size: 23px;
  }

  .player-info h3 {
    font-size: 19px;
  }
}