:root {
  --bg-a: #0f1115;
  --bg-b: #131722;
  --card: #171a21;
  --card-2: #1d212b;
  --border: #2a2f3a;
  --text: #e8eaed;
  --muted: #9aa1ac;
  --accent: #4f8cff;
  --accent-2: #7c5cff;
  --accent-dark: #2f6de0;
  --error: #ff5c5c;
  --success: #3ecf8e;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: radial-gradient(1200px 600px at 20% -10%, rgba(79, 140, 255, 0.12), transparent),
    radial-gradient(1000px 500px at 100% 10%, rgba(124, 92, 255, 0.1), transparent), var(--bg-a);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  padding: 24px;
}

.card {
  width: 100%;
  max-width: 560px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 32px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.35);
}

.app-header {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 24px;
}

.logo {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: white;
}

h1 {
  margin: 0 0 4px;
  font-size: 1.4rem;
}

.subtitle {
  margin: 0;
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.4;
}

.hidden {
  display: none !important;
}

/* Dropzone */

.dropzone {
  border: 2px dashed var(--border);
  border-radius: 14px;
  padding: 36px 16px;
  text-align: center;
  cursor: pointer;
  color: var(--muted);
  transition: border-color 0.15s ease, background 0.15s ease;
}

.dropzone:hover,
.dropzone.dragover {
  border-color: var(--accent);
  background: rgba(79, 140, 255, 0.06);
}

.upload-icon {
  color: var(--accent);
  margin-bottom: 8px;
}

.dropzone p {
  margin: 0;
}

.dropzone .hint {
  margin-top: 4px;
  font-size: 0.78rem;
  color: var(--muted);
  opacity: 0.8;
}

.link {
  color: var(--accent);
  text-decoration: underline;
}

/* Selected file preview */

.file-preview {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 14px;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--card-2);
}

.thumb-wrap {
  width: 56px;
  height: 56px;
  border-radius: 8px;
  overflow: hidden;
  background: var(--bg-a);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.thumb-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.thumb-fallback {
  color: var(--muted);
}

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

.file-name {
  margin: 0;
  font-weight: 500;
  font-size: 0.9rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.file-details {
  margin: 2px 0 0;
  font-size: 0.78rem;
  color: var(--muted);
}

.icon-btn {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.15s ease, border-color 0.15s ease;
}

.icon-btn:hover {
  color: var(--error);
  border-color: var(--error);
}

/* Options */

.options {
  display: flex;
  flex-direction: column;
  gap: 18px;
  margin: 24px 0;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.field-label {
  font-size: 0.82rem;
  color: var(--muted);
  display: flex;
  justify-content: space-between;
}

.field-label strong {
  color: var(--text);
  font-weight: 600;
}

.segmented {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 1fr;
  gap: 6px;
}

.segment {
  border: 1px solid var(--border);
  background: var(--card-2);
  color: var(--muted);
  border-radius: 10px;
  padding: 8px 6px;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  transition: border-color 0.15s ease, background 0.15s ease, color 0.15s ease;
  font-family: inherit;
}

.segment strong {
  font-size: 0.85rem;
  font-weight: 600;
  color: inherit;
}

.segment small {
  font-size: 0.68rem;
  opacity: 0.8;
}

.segment:hover {
  border-color: var(--accent);
}

.segment.active {
  border-color: var(--accent);
  background: rgba(79, 140, 255, 0.12);
  color: var(--text);
}

input[type="range"] {
  width: 100%;
  accent-color: var(--accent);
}

/* Submit button */

button#submitBtn {
  width: 100%;
  padding: 13px;
  border: none;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: white;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: opacity 0.15s ease, transform 0.1s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: inherit;
}

button#submitBtn:hover:not(:disabled) {
  opacity: 0.92;
}

button#submitBtn:active:not(:disabled) {
  transform: scale(0.99);
}

button#submitBtn:disabled {
  background: var(--border);
  color: var(--muted);
  cursor: not-allowed;
}

.spinner {
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* Progress */

.progress-wrap {
  margin-top: 18px;
}

.progress-bar {
  height: 8px;
  border-radius: 4px;
  background: var(--border);
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  transition: width 0.2s ease;
}

.progress-fill.indeterminate {
  width: 40% !important;
  animation: indeterminate 1.1s ease-in-out infinite;
}

@keyframes indeterminate {
  0% {
    margin-left: -40%;
  }
  100% {
    margin-left: 100%;
  }
}

#progressLabel {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 0.85rem;
  text-align: center;
}

/* Result step */

.result-step {
  text-align: center;
  padding: 8px 0 0;
}

.result-icon {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  margin: 0 auto 12px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.result-icon.success {
  background: rgba(62, 207, 142, 0.12);
  color: var(--success);
}

.result-title {
  margin: 0 0 4px;
  font-size: 1.2rem;
  font-weight: 600;
}

.result-savings {
  margin: 0 0 20px;
  color: var(--muted);
  font-size: 0.9rem;
}

.size-compare {
  display: flex;
  flex-direction: column;
  gap: 10px;
  text-align: left;
  margin-bottom: 24px;
}

.size-row {
  display: grid;
  grid-template-columns: 70px 1fr 70px;
  align-items: center;
  gap: 10px;
  font-size: 0.78rem;
  color: var(--muted);
}

.size-row span:last-child {
  text-align: right;
  color: var(--text);
}

.size-bar-track {
  height: 8px;
  border-radius: 4px;
  background: var(--card-2);
  overflow: hidden;
}

.size-bar {
  height: 100%;
  border-radius: 4px;
}

.size-bar.original {
  background: var(--muted);
  width: 100%;
}

.size-bar.optimized {
  background: linear-gradient(90deg, var(--accent), var(--success));
}

.result-actions {
  display: flex;
  gap: 10px;
}

.secondary-btn {
  flex: 1;
  padding: 11px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--card-2);
  color: var(--text);
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
  font-family: inherit;
  transition: border-color 0.15s ease;
}

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

/* Error */

.error-box {
  margin-top: 18px;
  padding: 12px 14px;
  border-radius: 10px;
  font-size: 0.88rem;
  background: rgba(255, 92, 92, 0.1);
  border: 1px solid rgba(255, 92, 92, 0.4);
  color: var(--error);
  display: flex;
  align-items: center;
  gap: 8px;
}

.error-box svg {
  flex-shrink: 0;
}

@media (max-width: 480px) {
  .card {
    padding: 24px 18px;
  }

  .segmented {
    grid-auto-flow: row;
    grid-template-columns: 1fr 1fr;
  }
}