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

:root {
  --green: #1D9E75;
  --green-dark: #0F6E56;
  --green-light: #E1F5EE;
  --green-text: #085041;
  --red-light: #FCEBEB;
  --red-text: #A32D2D;
  --gray-50: #F8F8F6;
  --gray-100: #F1EFE8;
  --gray-200: #E2E0D8;
  --gray-400: #888780;
  --gray-600: #5F5E5A;
  --gray-900: #1A1A18;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
}

html, body { height: 100%; }

body {
  font-family: 'DM Sans', sans-serif;
  font-size: 18px;
  line-height: 1.6;
  color: var(--gray-900);
  background: var(--gray-50);
  -webkit-font-smoothing: antialiased;
}

.kg-header {
  background: #fff;
  border-bottom: 0.5px solid var(--gray-200);
  padding: 14px 24px;
  position: sticky;
  top: 0;
  z-index: 10;
}

.kg-header-inner {
  max-width: 960px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 10px;
}

.kg-logo {
  font-family: 'Instrument Serif', serif;
  font-size: 24px;
  color: var(--gray-900);
  letter-spacing: -0.5px;
}

.kg-logo span { color: var(--green); }

.kg-badge {
  font-size: 13px;
  font-weight: 500;
  background: var(--green-light);
  color: var(--green-dark);
  padding: 2px 8px;
  border-radius: 20px;
}

.kg-tagline-header {
  font-size: 15px;
  color: var(--gray-400);
  font-weight: 300;
}

.kg-main {
  max-width: 960px;
  margin: 0 auto;
  padding: 40px 24px 60px;
}

.kg-hero {
  text-align: center;
  margin-bottom: 32px;
}

.kg-title {
  font-family: 'Instrument Serif', serif;
  font-size: 44px;
  font-weight: 400;
  color: var(--gray-900);
  letter-spacing: -1px;
  line-height: 1.2;
  margin-bottom: 10px;
}

.kg-subtitle {
  font-size: 18px;
  color: var(--gray-600);
  font-weight: 300;
}

.kg-panels {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 16px;
}

.kg-panel {
  background: #fff;
  border: 0.5px solid var(--gray-200);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.kg-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  border-bottom: 0.5px solid var(--gray-200);
  background: var(--gray-100);
}

.kg-panel-label {
  font-size: 13px;
  font-weight: 500;
  color: var(--gray-600);
  text-transform: uppercase;
  letter-spacing: 0.6px;
}

.kg-char-count {
  font-size: 13px;
  color: var(--gray-400);
}

.kg-input {
  flex: 1;
  width: 100%;
  min-height: 128px;
  border: none;
  outline: none;
  padding: 16px;
  font-family: 'DM Sans', sans-serif;
  font-size: 17px;
  line-height: 1.75;
  resize: none;
  background: #fff;
  color: var(--gray-900);
}

.kg-input::placeholder { color: var(--gray-400); }

.kg-output {
  flex: 1;
  min-height: 128px;
  padding: 16px;
  font-size: 17px;
  line-height: 1.75;
  color: var(--gray-900);
}

.kg-placeholder {
  color: var(--gray-400);
  font-style: italic;
  font-size: 16px;
}

.kg-panel-footer {
  padding: 10px 14px;
  border-top: 0.5px solid var(--gray-200);
  background: var(--gray-100);
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
}

.kg-footer-note {
  font-size: 14px;
  color: var(--gray-400);
  margin-right: auto;
}

.kg-cta-row {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 16px;
}

.kg-btn-cta {
  width: 220px;
  justify-content: center;
}

.kg-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-family: 'DM Sans', sans-serif;
  font-size: 16px;
  font-weight: 500;
  cursor: pointer;
  border: 0.5px solid var(--gray-200);
  background: #fff;
  color: var(--gray-900);
  transition: background 0.12s, border-color 0.12s;
}

.kg-btn:hover {
  background: var(--gray-100);
  border-color: var(--gray-400);
}

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

.kg-btn-ghost {
  background: transparent;
  border-color: transparent;
  color: var(--gray-600);
}

.kg-btn-ghost:hover {
  background: var(--gray-100);
  border-color: transparent;
}

.kg-btn-primary {
  background: var(--green);
  color: #fff;
  border-color: var(--green);
}

.kg-btn-primary:hover {
  background: var(--green-dark);
  border-color: var(--green-dark);
}

.kg-btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.kg-btn-cta {
  padding: 14px 48px;
  font-size: 18px;
  border-radius: var(--radius-lg);
}

.kg-copy-btn {
  padding: 3px 10px;
  font-size: 13px;
  font-weight: 500;
  border-radius: var(--radius-md);
  background: #fff;
  border: 0.5px solid var(--gray-200);
  color: var(--gray-600);
  cursor: pointer;
  font-family: 'DM Sans', sans-serif;
  transition: background 0.12s;
}

.kg-copy-btn:hover { background: var(--gray-100); }

.diff-added {
  background: var(--green-light);
  color: var(--green-text);
  border-radius: 3px;
  padding: 0 3px;
}

.diff-removed {
  background: var(--red-light);
  color: var(--red-text);
  text-decoration: line-through;
  border-radius: 3px;
  padding: 0 3px;
  margin-right: 1px;
}

.kg-no-errors {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 16px;
  color: var(--green-dark);
  background: var(--green-light);
  padding: 10px 14px;
  border-radius: var(--radius-md);
  margin-bottom: 12px;
}

.kg-loading {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--gray-600);
  font-size: 16px;
}

.kg-spinner {
  width: 18px;
  height: 18px;
  border: 2px solid var(--gray-200);
  border-top-color: var(--green);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  flex-shrink: 0;
}

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

.kg-explanations {
  background: #fff;
  border: 0.5px solid var(--gray-200);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: 32px;
  display: none;
}

.kg-explanations.visible { display: block; }

.kg-exp-header {
  padding: 10px 16px;
  border-bottom: 0.5px solid var(--gray-200);
  background: var(--gray-100);
  font-size: 13px;
  font-weight: 500;
  color: var(--gray-600);
  text-transform: uppercase;
  letter-spacing: 0.6px;
}

.kg-exp-body {
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.kg-exp-item {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  font-size: 16px;
  line-height: 1.6;
}

.kg-exp-num {
  min-width: 24px;
  height: 24px;
  background: var(--green-light);
  color: var(--green-dark);
  border-radius: 50%;
  font-size: 13px;
  font-weight: 500;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 2px;
  flex-shrink: 0;
}

.kg-exp-text {
  color: var(--gray-900);
  line-height: 1.6;
}

.kg-exp-detail {
  font-size: 15px;
  color: var(--gray-600);
  line-height: 1.6;
  font-weight: 300;
  border-left: 2px solid var(--green-light);
  padding-left: 10px;
  margin-top: 6px;
}

.kg-info {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 8px;
}

.kg-info-card {
  background: #fff;
  border: 0.5px solid var(--gray-200);
  border-radius: var(--radius-lg);
  padding: 18px;
  display: flex;
  gap: 14px;
  align-items: flex-start;
}

.kg-info-icon {
  font-family: 'Instrument Serif', serif;
  font-size: 22px;
  color: var(--green);
  min-width: 28px;
  text-align: center;
  margin-top: 1px;
}

.kg-info-title {
  font-size: 16px;
  font-weight: 500;
  color: var(--gray-900);
  margin-bottom: 4px;
}

.kg-info-text {
  font-size: 15px;
  color: var(--gray-600);
  line-height: 1.5;
  font-weight: 300;
}

.kg-footer {
  text-align: center;
  padding: 24px;
  font-size: 15px;
  color: var(--gray-400);
  border-top: 0.5px solid var(--gray-200);
  background: #fff;
}

.kg-error {
  color: var(--red-text);
  font-size: 16px;
  background: var(--red-light);
  padding: 10px 14px;
  border-radius: var(--radius-md);
}

@media (max-width: 680px) {
  .kg-panels { grid-template-columns: 1fr; }
  .kg-info { grid-template-columns: 1fr; }
  .kg-title { font-size: 32px; }
  .kg-tagline-header { display: none; }
}

.kg-drop-zone {
  position: relative;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.kg-drop-overlay {
  position: absolute;
  inset: 0;
  background: rgba(29, 158, 117, 0.08);
  border: 2px dashed var(--green);
  border-radius: var(--radius-md);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 10;
  pointer-events: none;
}

.kg-drop-overlay.active {
  display: flex;
}

.kg-drop-message {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  font-size: 16px;
  font-weight: 500;
  color: var(--green-dark);
}

.kg-drop-message span:first-child {
  font-size: 32px;
}

.kg-panel-footer {
  padding: 10px 14px;
  border-top: 0.5px solid var(--gray-200);
  background: var(--gray-100);
  display: flex;
  align-items: center;
  gap: 8px;
}

.kg-upload-btn {
  cursor: pointer;
}

.kg-extracting {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--green-dark);
  background: var(--green-light);
  padding: 8px 12px;
  border-radius: var(--radius-md);
  margin: 8px 14px;
}

.kg-btn-secondary {
  background: #fff;
  color: var(--green);
  border: 2px solid var(--green);
}

.kg-btn-secondary:hover {
  background: var(--green-light);
}

.kg-cta-row .kg-btn-cta {
  width: 220px;
  justify-content: center;
}

.kg-cta-row .kg-btn-cta {
  width: 260px;
  justify-content: center;
  white-space: nowrap;
}

.kg-hero-logo {
  font-family: 'Instrument Serif', serif;
  font-size: 72px;
  color: var(--gray-900);
  letter-spacing: -2px;
  line-height: 1;
  margin-bottom: 16px;
}

.kg-hero-logo span {
  color: var(--green);
}

.kg-word-section {
  margin-top: 40px;
}

.kg-word-header {
  text-align: center;
  margin-bottom: 24px;
}

.kg-word-title {
  font-family: 'Instrument Serif', serif;
  font-size: 28px;
  color: var(--gray-900);
  letter-spacing: -0.5px;
  margin-bottom: 6px;
}

.kg-word-subtitle {
  font-size: 16px;
  color: var(--gray-600);
  font-weight: 300;
}

.kg-subtitle {
  font-size: 15px;
}

@media (max-width: 680px) {
  .kg-word-section .kg-panels {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 680px) {
  .kg-word-section {
    padding: 0;
  }
}

.kg-detected {
  font-size: 12px;
  color: var(--green-dark);
  background: var(--green-light);
  padding: 3px 10px;
  border-radius: 20px;
  font-weight: 500;
  margin-right: auto;
  display: none;
}

.kg-detected.visible {
  display: inline-block;
}

.kg-panel-header {
  min-height: 42px;
}