:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: #1a1a24;
  --bg-hover: #22222e;
  
  --text-primary: #ffffff;
  --text-secondary: #8888a0;
  --text-muted: #555566;
  
  --accent-primary: #00d4aa;
  --accent-secondary: #00b894;
  --accent-glow: rgba(0, 212, 170, 0.3);
  
  --upload-color: #667eea;
  --download-color: #00d4aa;
  
  --error: #ff6b6b;
  --warning: #feca57;
  
  --font-display: 'JetBrains Mono', 'SF Mono', monospace;
  --font-body: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.45, 0, 0.55, 1);
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  background: 
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(0, 212, 170, 0.08), transparent),
    radial-gradient(ellipse 60% 40% at 100% 100%, rgba(102, 126, 234, 0.05), transparent);
  pointer-events: none;
  z-index: -1;
}

.app {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-lg) var(--space-xl);
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

.logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.logo-accent {
  color: var(--accent-primary);
}

.server-info {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.server-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--text-muted);
  transition: background 0.3s ease;
}

.server-dot.connected {
  background: var(--accent-primary);
  box-shadow: 0 0 8px var(--accent-glow);
}

.server-dot.error {
  background: var(--error);
}

.main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-xl);
}

.download-main {
  flex: 1;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: var(--space-xl);
}

.download-panel {
  width: 100%;
  max-width: 900px;
  background: var(--bg-card);
  border: 1px solid var(--bg-hover);
  border-radius: 18px;
  padding: var(--space-2xl);
}

.download-title {
  font-family: var(--font-display);
  font-size: 1.75rem;
  margin-bottom: var(--space-sm);
}

.download-subtitle {
  color: var(--text-secondary);
  line-height: 1.6;
}

.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-lg);
  margin-top: var(--space-xl);
}

.download-card {
  background: var(--bg-secondary);
  border: 1px solid var(--bg-hover);
  border-radius: 14px;
  padding: var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.download-card-title {
  font-family: var(--font-display);
  font-size: 1.05rem;
}

.download-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.download-link {
  color: var(--accent-primary);
  text-decoration: none;
  font-weight: 600;
}

.download-link:hover {
  color: var(--accent-secondary);
}

.download-meta {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.speed-section {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  animation: fadeIn 0.4s var(--ease-out);
  position: relative;
  min-height: 400px;
  padding-bottom: 60px;
}

.hidden {
  display: none !important;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.start-btn {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--bg-card) 0%, var(--bg-secondary) 100%);
  border: 2px solid var(--accent-primary);
  color: var(--text-primary);
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  transition: all 0.3s var(--ease-out);
  position: relative;
  overflow: hidden;
}

.start-btn::before {
  content: '';
  position: absolute;
  inset: -2px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent-primary), var(--upload-color));
  opacity: 0;
  transition: opacity 0.3s ease;
  z-index: -1;
}

.start-btn:hover {
  transform: scale(1.05);
  box-shadow: 
    0 0 30px var(--accent-glow),
    0 10px 40px rgba(0, 0, 0, 0.4);
}

.start-btn:hover::before {
  opacity: 0.15;
}

.start-btn:active {
  transform: scale(0.98);
}

.start-btn-text {
  font-family: var(--font-display);
  font-size: 3rem;
  font-weight: 700;
  color: var(--accent-primary);
  text-shadow: 0 0 20px var(--accent-glow);
}

.start-btn-hint {
  font-size: 0.75rem;
  color: var(--text-secondary);
  max-width: 120px;
}

.speed-display {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.speed-number {
  font-family: var(--font-display);
  font-size: clamp(5rem, 22vw, 12rem);
  font-weight: 800;
  line-height: 0.85;
  color: var(--text-primary);
  text-shadow: 0 0 100px var(--accent-glow);
  transition: color 0.3s ease;
  letter-spacing: -0.02em;
}

.speed-number.downloading {
  color: var(--download-color);
}

.speed-number.uploading {
  color: var(--upload-color);
}

.speed-unit {
  font-family: var(--font-display);
  font-size: 1.25rem;
  color: var(--text-secondary);
  letter-spacing: 0.1em;
  margin-top: var(--space-xs);
}

.test-type {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-top: var(--space-sm);
  opacity: 0.8;
}

.progress-ring-container {
  position: absolute;
  width: 280px;
  height: 280px;
  pointer-events: none;
}

.progress-ring {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.progress-ring-bg {
  fill: none;
  stroke: var(--bg-card);
  stroke-width: 4;
}

.progress-ring-fill {
  fill: none;
  stroke: var(--accent-primary);
  stroke-width: 4;
  stroke-linecap: round;
  stroke-dasharray: 565.48;
  stroke-dashoffset: 565.48;
  transition: stroke-dashoffset 0.3s ease, stroke 0.3s ease;
}

.progress-ring-fill.downloading {
  stroke: var(--download-color);
}

.progress-ring-fill.uploading {
  stroke: var(--upload-color);
}

.results-main {
  display: flex;
  gap: var(--space-xl);
  margin-bottom: var(--space-2xl);
}

.result-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--space-xl);
  background: var(--bg-card);
  border-radius: 16px;
  min-width: 160px;
  border: 1px solid transparent;
  animation: slideUp 0.5s var(--ease-out) backwards;
}

.result-card:nth-child(1) { animation-delay: 0.1s; }
.result-card:nth-child(2) { animation-delay: 0.2s; }

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.result-primary {
  border-color: var(--download-color);
}

.result-secondary {
  border-color: var(--upload-color);
}

.result-icon {
  font-size: 1.5rem;
  margin-bottom: var(--space-sm);
  opacity: 0.6;
}

.result-primary .result-icon { color: var(--download-color); }
.result-secondary .result-icon { color: var(--upload-color); }

.result-value {
  font-family: var(--font-display);
  font-size: 3rem;
  font-weight: 700;
  line-height: 1;
  margin-bottom: var(--space-xs);
}

.result-primary .result-value { color: var(--download-color); }
.result-secondary .result-value { color: var(--upload-color); }

.result-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.result-unit {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: var(--space-xs);
}

.results-extra {
  display: flex;
  gap: var(--space-2xl);
  margin-bottom: var(--space-2xl);
  animation: slideUp 0.5s var(--ease-out) 0.3s backwards;
}

.extra-stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-xs);
}

.extra-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.extra-value {
  font-family: var(--font-display);
  font-size: 1.25rem;
  color: var(--text-secondary);
}

.results-details {
  margin-top: var(--space-2xl);
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--bg-hover);
  animation: slideUp 0.5s var(--ease-out) 0.4s backwards;
}

.detail-section {
  margin-bottom: var(--space-xl);
}

.detail-section:last-child {
  margin-bottom: 0;
}

.detail-title {
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-md);
  font-weight: 600;
}

.detail-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--space-md);
}

.detail-item {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.detail-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.detail-value {
  font-family: var(--font-display);
  font-size: 1rem;
  color: var(--text-secondary);
}

.results-actions {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  margin-top: var(--space-2xl);
  animation: slideUp 0.5s var(--ease-out) 0.5s backwards;
}

.cancel-btn {
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  background: transparent;
  border: 1px solid var(--text-muted);
  color: var(--text-muted);
  padding: var(--space-xs) var(--space-md);
  border-radius: 6px;
  font-family: var(--font-body);
  font-size: 0.75rem;
  cursor: pointer;
  transition: all 0.2s ease;
  opacity: 0.7;
}

.cancel-btn:hover {
  border-color: var(--error);
  color: var(--error);
  opacity: 1;
}

.restart-btn {
  background: transparent;
  border: 1px solid var(--text-muted);
  color: var(--text-secondary);
  padding: var(--space-sm) var(--space-lg);
  border-radius: 8px;
  font-family: var(--font-body);
  font-size: 0.875rem;
  cursor: pointer;
  transition: all 0.2s ease;
  animation: slideUp 0.5s var(--ease-out) 0.4s backwards;
}

.restart-btn:hover {
  border-color: var(--accent-primary);
  color: var(--accent-primary);
}

.footer {
  padding: var(--space-lg) var(--space-xl);
  text-align: center;
}

.footer-links {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
}

.footer-link {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.75rem;
  cursor: pointer;
  text-decoration: none;
  transition: color 0.2s ease;
}

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

.footer-divider {
  color: var(--text-muted);
}

.modal {
  border: none;
  padding: 0;
  width: min(92vw, 460px);
  margin: auto;
  background: var(--bg-card);
  border-radius: 16px;
  border: 1px solid var(--bg-hover);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.45);
}

.modal[open] {
  animation: modalIn 0.2s var(--ease-out);
}

.modal::backdrop {
  background: rgba(0, 0, 0, 0.72);
  backdrop-filter: blur(4px);
}

.modal-content {
  display: flex;
  flex-direction: column;
  max-height: min(80vh, 560px);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-lg);
  border-bottom: 1px solid var(--bg-hover);
}

.modal-header h2 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.modal-close {
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 1.5rem;
  cursor: pointer;
  line-height: 1;
  padding: var(--space-xs);
  transition: color 0.2s ease;
}

.modal-close:hover {
  color: var(--text-primary);
}

.modal-body {
  padding: var(--space-lg);
  overflow: auto;
}

.setting-group {
  margin-bottom: var(--space-lg);
}

.setting-group:last-child {
  margin-bottom: 0;
}

.setting-label {
  display: flex;
  align-items: center;
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-sm);
  cursor: pointer;
}

.setting-hint {
  display: block;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: var(--space-xs);
  line-height: 1.4;
}

.setting-input {
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  background: var(--bg-secondary);
  border: 1px solid var(--bg-hover);
  border-radius: 8px;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.875rem;
}

.setting-input:focus {
  outline: none;
  border-color: var(--accent-primary);
}

.setting-input:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
}

.modal-close:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
  border-radius: 6px;
}

select.setting-input {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%238888a0' d='M6 9L1 4h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--space-md) center;
  padding-right: calc(var(--space-md) + 16px);
}

.server-status {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  margin-top: var(--space-md);
  font-size: 0.75rem;
  color: var(--text-muted);
}

.server-status::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--text-muted);
}

.server-status.connected {
  color: var(--text-secondary);
}

.server-status.connected::before {
  background: var(--accent-primary);
  box-shadow: 0 0 6px var(--accent-primary);
}

.server-status.error {
  color: var(--text-secondary);
}

.server-status.error::before {
  background: var(--error);
  box-shadow: 0 0 6px var(--error);
}

#customServerGroup {
  margin-top: var(--space-md);
}

/* Toggle Switch */
.toggle {
  position: relative;
  display: inline-block;
  width: 48px;
  height: 26px;
  cursor: pointer;
}

.toggle input {
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-slider {
  position: absolute;
  inset: 0;
  background: var(--bg-secondary);
  border: 1px solid var(--text-muted);
  border-radius: 26px;
  transition: all 0.2s var(--ease-out);
}

.toggle-slider::before {
  content: '';
  position: absolute;
  left: 3px;
  top: 50%;
  transform: translateY(-50%);
  width: 18px;
  height: 18px;
  background: var(--text-secondary);
  border-radius: 50%;
  transition: all 0.2s var(--ease-out);
}

.toggle input:checked + .toggle-slider {
  background: var(--accent-primary);
  border-color: var(--accent-primary);
}

.toggle input:checked + .toggle-slider::before {
  left: calc(100% - 21px);
  background: var(--bg-primary);
}

.toggle input:focus + .toggle-slider {
  box-shadow: 0 0 0 2px var(--accent-glow);
}

.setting-group .setting-label {
  justify-content: space-between;
}

.toast {
  position: fixed;
  bottom: var(--space-xl);
  left: 50%;
  transform: translateX(-50%);
  background: var(--error);
  color: var(--text-primary);
  padding: var(--space-sm) var(--space-lg);
  border-radius: 8px;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.875rem;
  animation: slideUp 0.3s var(--ease-out);
  z-index: 100;
}

.toast-icon {
  font-size: 1rem;
}

@keyframes modalIn {
  from {
    opacity: 0;
    transform: translateY(8px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@media (max-width: 600px) {
  .header {
    padding: var(--space-md);
  }
  
  .logo {
    font-size: 1.25rem;
  }
  
  .start-btn {
    width: 160px;
    height: 160px;
  }
  
  .start-btn-text {
    font-size: 2.5rem;
  }
  
  .speed-section {
    width: 220px;
    height: 220px;
  }
  
  .speed-number {
    font-size: 4rem;
  }
  
  .speed-display {
    max-width: 300px;
  }
  
  .progress-ring-container {
    width: 220px;
    height: 220px;
  }
  
  .results-main {
    flex-direction: column;
    gap: var(--space-md);
  }
  
  .result-card {
    min-width: 200px;
  }
  
  .results-extra {
    flex-direction: column;
    gap: var(--space-md);
  }
  
  .results-details {
    margin-top: var(--space-lg);
    padding-top: var(--space-lg);
  }
  
  .detail-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .results-actions {
    flex-direction: column;
  }
  
  .restart-btn {
    width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .modal[open] {
    animation: none;
  }
}

@keyframes pulse {
  0%, 100% { opacity: 0.6; }
  50% { opacity: 1; }
}

.loading {
  animation: pulse 1.5s ease-in-out infinite;
}

@keyframes countUp {
  from { opacity: 0; }
  to { opacity: 1; }
}

.counting {
  animation: countUp 0.1s ease-out;
}