:root {
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* HSL Tailored Color Palette */
  --bg-dark: hsl(224, 25%, 6%);
  --bg-card: hsla(223, 20%, 12%, 0.6);
  --border-card: hsla(223, 20%, 20%, 0.4);
  
  --primary: hsl(252, 90%, 65%);
  --primary-hover: hsl(252, 90%, 72%);
  --primary-glow: hsla(252, 90%, 65%, 0.25);
  
  --secondary: hsl(210, 20%, 18%);
  --secondary-hover: hsl(210, 20%, 24%);
  
  --success: hsl(142, 70%, 45%);
  --success-glow: hsla(142, 70%, 45%, 0.2);
  --warning: hsl(38, 92%, 50%);
  --danger: hsl(346, 84%, 61%);
  
  --text-primary: hsl(210, 20%, 98%);
  --text-secondary: hsl(215, 15%, 70%);
  --text-muted: hsl(215, 10%, 45%);
  
  --radius-lg: 16px;
  --radius-md: 10px;
  --radius-sm: 6px;
  
  --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
  background-color: var(--bg-dark);
  color: var(--text-primary);
  font-family: var(--font-sans);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  overflow-x: hidden;
  position: relative;
}

/* Background decoration glow */
.background-glow {
  position: absolute;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--primary-glow) 0%, transparent 70%);
  top: -200px;
  left: calc(50% - 300px);
  z-index: -1;
  pointer-events: none;
  filter: blur(40px);
}

.app-container {
  width: 100%;
  max-width: 800px;
  padding: 2.5rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

/* Header */
.app-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border-card);
  padding-bottom: 1.5rem;
}

.logo-container {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.logo-shield {
  width: 42px;
  height: 42px;
  background: linear-gradient(135deg, var(--primary), hsl(280, 80%, 60%));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  box-shadow: 0 4px 15px var(--primary-glow);
}

.logo-shield svg {
  width: 22px;
  height: 22px;
}

h1 {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.025em;
  background: linear-gradient(to right, var(--text-primary), var(--text-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.subtitle {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 0.1rem;
}

/* Badges */
.badge {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  border-radius: 9999px;
  border: 1px solid transparent;
  transition: var(--transition-smooth);
}

.badge-disconnected {
  background-color: hsla(346, 84%, 61%, 0.1);
  color: var(--danger);
  border-color: hsla(346, 84%, 61%, 0.2);
}

.badge-connecting {
  background-color: hsla(38, 92%, 50%, 0.1);
  color: var(--warning);
  border-color: hsla(38, 92%, 50%, 0.2);
}

.badge-connected {
  background-color: hsla(142, 70%, 45%, 0.1);
  color: var(--success);
  border-color: hsla(142, 70%, 45%, 0.2);
  box-shadow: 0 0 10px var(--success-glow);
}

.app-main {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;}

/* Cards (Glassmorphism) */
.card {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.3);
}

.card h2 {
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 1.5rem;
}

/* Room Setup Grid */
.setup-grid {
  display: flex;
  align-items: stretch;
  gap: 1.5rem;
}

@media (max-width: 600px) {
  .setup-grid {
    flex-direction: column;
  }
  .divider-text {
    align-self: center;
  }
}

.setup-col {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.75rem;
}

.setup-col h3 {
  font-size: 0.95rem;
  color: var(--text-primary);
  font-weight: 600;
}

.divider-text {
  display: flex;
  align-items: center;
  color: var(--text-muted);
  font-size: 0.8rem;
  font-weight: 600;
}

/* Buttons */
.btn {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 550;
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: var(--transition-smooth);
}

.btn-primary {
  background-color: var(--primary);
  color: white;
  box-shadow: 0 4px 14px var(--primary-glow);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px var(--primary-glow);
}

.btn-secondary {
  background-color: var(--secondary);
  color: var(--text-primary);
  border-color: var(--border-card);
}

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

.btn-danger {
  background-color: hsla(346, 84%, 61%, 0.1);
  color: var(--danger);
  border: 1px solid hsla(346, 84%, 61%, 0.2);
}

.btn-danger:hover {
  background-color: hsla(346, 84%, 61%, 0.2);
}

.btn-sm {
  padding: 0.4rem 0.8rem;
  font-size: 0.8rem;
  border-radius: var(--radius-sm);
}

.btn-block {
  width: 100%;
}

.btn-icon {
  width: 16px;
  height: 16px;
}

/* Text Inputs */
input[type="text"] {
  width: 100%;
  padding: 0.75rem 1rem;
  background-color: hsla(223, 20%, 8%, 0.5);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  color: white;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  outline: none;
  transition: var(--transition-smooth);
}

input[type="text"]:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.join-group {
  display: flex;
  gap: 0.5rem;
}

/* Connection Info */
.connection-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1.5rem;
}

.text-room-id {
  font-family: var(--font-mono);
  color: var(--primary);
  font-weight: 600;
  letter-spacing: 0.05em;
}

.secure-line-indicator {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 0.25rem;
}

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

.badge-connected ~ .app-main .status-dot,
.secure-line-indicator.secure .status-dot {
  background-color: var(--success);
}

/* Pulse animation */
.pulse {
  animation: pulse-ring 1.5s infinite;
}

@keyframes pulse-ring {
  0% {
    box-shadow: 0 0 0 0 hsla(142, 70%, 45%, 0.7);
  }
  70% {
    box-shadow: 0 0 0 6px hsla(142, 70%, 45%, 0);
  }
  100% {
    box-shadow: 0 0 0 0 hsla(142, 70%, 45%, 0);
  }
}

/* Fingerprint (Security Code Verification) */
.fingerprint-wrapper {
  background: hsla(223, 20%, 8%, 0.4);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  padding: 1.25rem;
}

.fingerprint-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.icon-sm {
  width: 16px;
  height: 16px;
}

.fingerprint-desc {
  font-size: 0.8rem !important;
  color: var(--text-muted) !important;
  margin-bottom: 1rem !important;
}

.fingerprint-code {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-align: center;
  padding: 1rem;
  background-color: hsla(223, 20%, 6%, 0.8);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-card);
  color: var(--text-primary);
  user-select: all;
  margin-bottom: 1.25rem;
}

.fingerprint-action {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
  cursor: pointer;
}

.fingerprint-action input[type="checkbox"] {
  cursor: pointer;
  accent-color: var(--primary);
  width: 16px;
  height: 16px;
}

.fingerprint-action label {
  cursor: pointer;
  user-select: none;
}

/* Dropzone styling */
.dropzone {
  border: 2px dashed var(--border-card);
  border-radius: var(--radius-lg);
  padding: 3rem 2rem;
  text-align: center;
  cursor: pointer;
  transition: var(--transition-smooth);
  background: hsla(223, 20%, 8%, 0.2);
}

.dropzone:hover, .dropzone.dragover {
  border-color: var(--primary);
  background: hsla(252, 90%, 65%, 0.05);
}

.dropzone-icon {
  width: 48px;
  height: 48px;
  color: var(--text-muted);
  margin-bottom: 1rem;
  transition: var(--transition-smooth);
}

.dropzone:hover .dropzone-icon {
  color: var(--primary);
  transform: translateY(-4px);
}

.dropzone-main-text {
  font-size: 0.95rem;
  color: var(--text-primary);
  font-weight: 500;
  margin-bottom: 0.4rem;
}

.dropzone-main-text span {
  color: var(--primary);
  text-decoration: underline;
}

.dropzone-sub-text {
  font-size: 0.8rem !important;
  color: var(--text-muted) !important;
  margin-bottom: 0 !important;
}

/* Selected File Details */
.file-details {
  background: hsla(223, 20%, 8%, 0.4);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  padding: 1rem;
  margin-top: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.file-info-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.file-info-icon {
  width: 36px;
  height: 36px;
  background: hsla(252, 90%, 65%, 0.1);
  border-radius: var(--radius-sm);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
}

.file-info-icon svg {
  width: 20px;
  height: 20px;
}

.file-info-text {
  flex: 1;
  min-width: 0;
}

.file-name {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.file-size {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 0.1rem;
}

.btn-close {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0.25rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition-smooth);
}

.btn-close:hover {
  background: hsla(0, 0%, 100%, 0.05);
  color: var(--text-primary);
}

.btn-close svg {
  width: 18px;
  height: 18px;
}

/* Progress Section */
.progress-container {
  margin-top: 1.25rem;
  padding: 1.25rem;
  background: hsla(223, 20%, 8%, 0.4);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
}

.progress-header {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.progress-bar-bg {
  width: 100%;
  height: 6px;
  background: hsla(223, 20%, 6%, 0.8);
  border-radius: 3px;
  overflow: hidden;
  margin-bottom: 0.5rem;
}

.progress-bar-fill {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--primary), hsl(280, 80%, 60%));
  border-radius: 3px;
  transition: width 0.1s linear;
}

.progress-stats {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* Audit Log / Crypto Console */
.log-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.btn-link {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.8rem;
  cursor: pointer;
  text-decoration: underline;
  transition: var(--transition-smooth);
}

.btn-link:hover {
  color: var(--text-secondary);
}

.log-console {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  background-color: hsl(224, 25%, 4%);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  padding: 1rem;
  height: 200px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  scroll-behavior: smooth;
  /* Custom Scrollbars */
  scrollbar-width: thin;
  scrollbar-color: var(--border-card) transparent;
}

.log-console::-webkit-scrollbar {
  width: 6px;
}
.log-console::-webkit-scrollbar-thumb {
  background: var(--border-card);
  border-radius: 3px;
}

.log-entry {
  line-height: 1.4;
  word-break: break-all;
}

.log-system {
  color: hsl(210, 15%, 60%);
}

.log-crypto {
  color: hsl(190, 85%, 65%);
}

.log-p2p {
  color: hsl(280, 75%, 70%);
}

.log-send {
  color: hsl(45, 85%, 60%);
}

.log-recv {
  color: hsl(145, 75%, 60%);
}

.log-error {
  color: var(--danger);
  font-weight: 500;
}

/* Footer */
.app-footer {
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 1rem;
}

/* Helpers */
.hidden {
  display: none !important;
}