:root {
  --bg-dark: #0f1016;
  --panel-bg: rgba(26, 28, 38, 0.65);
  --panel-border: rgba(255, 255, 255, 0.08);
  --accent-color: #2563eb;
  --accent-hover: #1d4ed8;
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --input-bg: #151722;
  --danger-color: #ef4444;
  --success-color: #10b981;
}

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

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background: radial-gradient(circle at center, #1b1c2b 0%, #090a0f 100%);
  color: var(--text-main);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Nav Menu Header */
header.app-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  background: rgba(15, 16, 22, 0.8);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--panel-border);
  z-index: 100;
}

.brand-title {
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.brand-dot {
  width: 10px;
  height: 10px;
  background-color: var(--success-color);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--success-color);
}

nav.app-menu {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

nav.app-menu a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.2s ease;
}

nav.app-menu a:hover, nav.app-menu a.active {
  color: var(--text-main);
}

.logout-btn {
  color: var(--danger-color) !important;
}

/* Main Container */
main.app-container {
  flex: 1;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

/* Auth / Login Page Layout */
body.login-page {
  justify-content: center;
  align-items: center;
}

.login-card {
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 16px;
  padding: 2.5rem;
  width: 100%;
  max-width: 420px;
  backdrop-filter: blur(20px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
  text-align: center;
}

.login-card h2 {
  font-size: 1.75rem;
  margin-bottom: 0.5rem;
  font-weight: 700;
}

.login-card p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 2rem;
}

.form-group {
  margin-bottom: 1.25rem;
  text-align: left;
}

.form-group label {
  display: block;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.form-group input {
  width: 100%;
  background: var(--input-bg);
  border: 1px solid var(--panel-border);
  border-radius: 8px;
  padding: 0.75rem 1rem;
  color: var(--text-main);
  font-size: 1rem;
  outline: none;
  transition: border-color 0.2s ease;
}

.form-group input:focus {
  border-color: var(--accent-color);
}

.btn-primary, #loginButton button {
  width: 100%;
  background: var(--accent-color);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 0.85rem;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.2s ease;
  margin-top: 1rem;
}

.btn-primary:hover, #loginButton button:hover {
  background-color: var(--accent-hover);
}

.btn-danger, #terminate button {
  width: 100%;
  background: linear-gradient(135deg, #c0392b, #e74c3c);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 0.75rem;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s ease, transform 0.1s ease;
  letter-spacing: 0.02em;
}

.btn-danger:hover, #terminate button:hover {
  background: linear-gradient(135deg, #a93226, #cb4335);
  transform: translateY(-1px);
}

/* Conference Grid Layout */
.conference-layout {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 1.5rem;
  height: calc(100vh - 120px);
  min-height: 500px;
}

.video-section {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.video-grid {
  flex: 1;
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 16px;
  overflow: hidden;
  position: relative;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 10px;
  padding: 10px;
}

.video-card {
  position: relative;
  background: #000;
  border-radius: 12px;
  overflow: hidden;
  aspect-ratio: 16/9;
}

.video-card video {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.video-label {
  position: absolute;
  bottom: 10px;
  left: 10px;
  background: rgba(0, 0, 0, 0.6);
  padding: 4px 8px;
  border-radius: 4px;
  font-size: 0.75rem;
  color: #fff;
  z-index: 10;
}

/* Chat & Users Panel */
.panel-sidebar {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 16px;
  padding: 1.25rem;
  height: 100%;
}

.sidebar-section {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.sidebar-section.chat-section {
  flex: 1;
  min-height: 0;
}

.sidebar-title {
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  font-weight: 700;
  border-bottom: 1px solid var(--panel-border);
  padding-bottom: 0.5rem;
}

.users-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  max-height: 120px;
  overflow-y: auto;
}

.user-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
}

.user-status {
  width: 8px;
  height: 8px;
  background-color: var(--success-color);
  border-radius: 50%;
}

.chat-history {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  padding-right: 5px;
}

.chat-msg {
  background: rgba(255, 255, 255, 0.03);
  border-radius: 8px;
  padding: 0.6rem 0.8rem;
  font-size: 0.85rem;
  line-height: 1.4;
}

.chat-author {
  font-weight: 600;
  color: var(--accent-color);
  margin-bottom: 2px;
}

.chat-input-wrapper {
  display: flex;
  gap: 0.5rem;
}

.chat-input-wrapper input {
  flex: 1;
  background: var(--input-bg);
  border: 1px solid var(--panel-border);
  border-radius: 8px;
  padding: 0.6rem 0.8rem;
  color: var(--text-main);
  outline: none;
  font-size: 0.85rem;
}

.chat-input-wrapper input:focus {
  border-color: var(--accent-color);
}

.btn-send {
  background: var(--accent-color);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 0 1rem;
  cursor: pointer;
  font-weight: 600;
  font-size: 0.85rem;
}

.btn-send:hover {
  background-color: var(--accent-hover);
}

/* Footer Controls */
.video-controls {
  display: flex;
  justify-content: center;
  gap: 1rem;
  padding: 1rem;
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 12px;
}

.btn-control {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid var(--panel-border);
  color: #fff;
  border-radius: 50%;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-control:hover {
  background: rgba(255, 255, 255, 0.15);
  transform: translateY(-2px);
}

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

.btn-control svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
}