:root {
  --primary: #2563eb;
  --primary-dark: #1e40af;
  --success: #16a34a;
  --warning: #ea580c;
  --error: #dc2626;
  --bg: #f8fafc;
  --card-bg: #ffffff;
  --border: #e2e8f0;
  --text: #0f172a;
  --text-muted: #64748b;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.05), 0 4px 12px rgba(0, 0, 0, 0.05);
}

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

html, body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 16px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
header {
  text-align: center;
  margin: 16px 0 24px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 24px;
  font-weight: 700;
  color: var(--primary-dark);
}

.logo-icon {
  font-size: 32px;
}

.subtitle {
  margin-top: 4px;
  color: var(--text-muted);
  font-size: 14px;
}

/* Cards */
main {
  flex: 1;
}

.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 16px;
  box-shadow: var(--shadow);
}

.card h2, .card h3 {
  font-size: 16px;
  margin-bottom: 12px;
  color: var(--text);
}

.card h2 {
  font-size: 18px;
  color: var(--primary-dark);
}

/* OS Info */
.os-info {
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border: 1px solid #bfdbfe;
}

.os-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px 16px;
  font-size: 14px;
  margin-bottom: 12px;
}

.os-grid div, .os-local, .os-obs {
  font-size: 14px;
}

.os-local, .os-obs {
  margin-top: 8px;
  padding-top: 8px;
  border-top: 1px dashed #bfdbfe;
}

/* Radio cards */
.radio-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.radio-card {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px;
  border: 2px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.15s;
  background: #fff;
}

.radio-card:hover {
  border-color: var(--primary);
  background: #f8fafc;
}

.radio-card input[type="radio"] {
  width: 20px;
  height: 20px;
  accent-color: var(--primary);
  margin: 0;
  flex-shrink: 0;
}

.radio-card:has(input:checked) {
  border-color: var(--primary);
  background: #eff6ff;
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.radio-icon {
  font-size: 22px;
}

.radio-label {
  flex: 1;
  font-weight: 500;
}

/* Field label */
.field-label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  margin: 16px 0 6px;
  color: var(--text);
}

.hint {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 12px;
}

textarea {
  width: 100%;
  padding: 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-family: inherit;
  font-size: 14px;
  resize: vertical;
  background: #fff;
}

textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* Upload */
.upload-area {
  margin-bottom: 12px;
}

.upload-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px;
  background: var(--primary);
  color: #fff;
  border-radius: var(--radius);
  cursor: pointer;
  font-weight: 600;
  font-size: 15px;
  transition: background 0.15s;
}

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

.upload-icon {
  font-size: 20px;
}

.fotos-preview {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: 8px;
  margin-bottom: 8px;
}

.foto-thumb {
  position: relative;
  aspect-ratio: 1;
  border-radius: 8px;
  overflow: hidden;
  background: var(--border);
}

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

.foto-thumb .remove {
  position: absolute;
  top: 4px;
  right: 4px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.6);
  color: #fff;
  border: none;
  cursor: pointer;
  font-size: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.foto-thumb .upload-status {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: rgba(0, 0, 0, 0.6);
  color: #fff;
  font-size: 11px;
  padding: 2px 4px;
  text-align: center;
}

/* Stars */
.star-rating {
  display: flex;
  gap: 6px;
  justify-content: center;
  margin-bottom: 8px;
}

.star {
  background: none;
  border: none;
  font-size: 40px;
  color: #cbd5e1;
  cursor: pointer;
  padding: 0;
  transition: color 0.1s, transform 0.1s;
}

.star:hover, .star.active {
  color: #fbbf24;
}

.star:active {
  transform: scale(1.2);
}

/* Submit */
.submit-area {
  margin: 24px 0 32px;
}

.btn-primary {
  width: 100%;
  padding: 16px;
  background: var(--success);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  font-size: 17px;
  font-weight: 700;
  cursor: pointer;
  transition: background 0.15s;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.btn-primary:hover:not(:disabled) {
  background: #15803d;
}

.btn-primary:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* State cards */
.state-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 40px 20px;
  text-align: center;
  box-shadow: var(--shadow);
  margin: 40px 0;
}

.state-icon {
  font-size: 64px;
  margin-bottom: 16px;
}

.state-card h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.state-card p {
  color: var(--text-muted);
}

/* Spinner */
.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: 0 auto 16px;
}

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

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

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

footer {
  text-align: center;
  margin-top: 32px;
  padding: 16px 0;
  font-size: 12px;
  color: var(--text-muted);
}

/* Mobile */
@media (max-width: 480px) {
  .container {
    padding: 12px;
  }
  .card {
    padding: 16px;
  }
  .os-grid {
    grid-template-columns: 1fr;
  }
  .logo {
    font-size: 20px;
  }
  .logo-icon {
    font-size: 28px;
  }
}