:root {
  --bg: #f5f6f8;
  --bg-card: #ffffff;
  --bg-hover: #f0f1f3;
  --border: #e2e4e8;
  --border-light: #eef0f2;
  --text: #1a1d23;
  --text-secondary: #5f6874;
  --text-muted: #9199a6;
  --primary: #3b82f6;
  --primary-light: #dbeafe;
  --primary-dark: #2563eb;
  --success: #10b981;
  --success-light: #d1fae5;
  --warning: #f59e0b;
  --warning-light: #fef3c7;
  --danger: #ef4444;
  --danger-light: #fee2e2;
  --purple: #8b5cf6;
  --purple-light: #ede9fe;
  --pink: #ec4899;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.08), 0 1px 2px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 4px 12px rgba(0, 0, 0, 0.1);
  --radius: 10px;
  --radius-sm: 6px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --transition: 0.15s ease;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 14px;
  line-height: 1.5;
  min-height: 100vh;
}

.app {
  max-width: 1200px;
  margin: 0 auto;
  padding: 24px;
}

/* Header */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 20px;
  margin-bottom: 20px;
  box-shadow: var(--shadow);
}

.header-left {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.logo {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
}

.logo-desc {
  font-size: 12px;
  color: var(--text-muted);
}

.header-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

.select-group {
  display: flex;
  align-items: center;
  gap: 8px;
}

.select-group label {
  font-size: 12px;
  color: var(--text-secondary);
  font-weight: 500;
}

select {
  appearance: none;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  padding: 6px 28px 6px 10px;
  font-size: 13px;
  font-family: var(--font);
  cursor: pointer;
  outline: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%239199a6' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 8px center;
  transition: border-color var(--transition);
}

select:hover { border-color: var(--primary); }
select:focus { border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-light); }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 8px 14px;
  font-size: 13px;
  font-weight: 500;
  font-family: var(--font);
  cursor: pointer;
  background: var(--bg-card);
  color: var(--text);
  transition: all var(--transition);
  outline: none;
}

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

.btn-icon {
  width: 36px;
  height: 36px;
  padding: 0;
}

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

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

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

.full-width {
  width: 100%;
  grid-column: 1 / -1;
}

/* Main Grid */
.main {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 16px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow);
}

.card-header {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
}

.card-header h3 {
  font-size: 14px;
  font-weight: 600;
  flex: 1;
}

.card-icon {
  width: 18px;
  height: 18px;
  color: var(--primary);
  flex-shrink: 0;
}

/* CGPA Card */
.card-cgpa {
  grid-column: span 3;
  text-align: center;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.cgpa-display {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  margin-bottom: 16px;
}

.cgpa-label {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-muted);
}

.cgpa-value {
  font-size: 42px;
  font-weight: 700;
  line-height: 1;
  color: var(--text);
}

.cgpa-class {
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
}

.cgpa-meta {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  border-top: 1px solid var(--border-light);
  padding-top: 14px;
}

.meta-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.meta-label {
  font-size: 10px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.3px;
  color: var(--text-muted);
}

.meta-value {
  font-size: 13px;
  font-weight: 600;
}

/* Summary Card */
.card-summary { grid-column: span 4; }

.summary-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.summary-item {
  background: var(--bg);
  border-radius: var(--radius-sm);
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.summary-item.highlight {
  background: var(--primary-light);
  border: 1px solid var(--primary);
}

.summary-label {
  font-size: 11px;
  color: var(--text-secondary);
}

.summary-value {
  font-size: 18px;
  font-weight: 700;
}

.summary-item.highlight .summary-value {
  color: var(--primary-dark);
}

/* Progress Card */
.card-progress { grid-column: span 5; }

.progress-body {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.progress-stats {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
}

.progress-credits {
  display: flex;
  align-items: baseline;
  gap: 3px;
  flex-wrap: wrap;
}

.credits-done {
  font-size: 28px;
  font-weight: 700;
}

.credits-sep {
  font-size: 18px;
  color: var(--text-muted);
}

.credits-total {
  font-size: 18px;
  color: var(--text-secondary);
}

.credits-label {
  width: 100%;
  font-size: 12px;
  color: var(--text-muted);
}

.progress-pct {
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
}

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

.progress-fill {
  height: 100%;
  background: var(--primary);
  border-radius: 4px;
  transition: width 0.4s ease;
}

.progress-control {
  display: flex;
  align-items: center;
  gap: 10px;
}

.progress-control label {
  font-size: 12px;
  color: var(--text-secondary);
  font-weight: 500;
}

.progress-control input {
  width: 70px;
  text-align: center;
}

/* Classification Card */
.card-classification { grid-column: span 3; }

.class-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.class-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 10px;
  font-size: 13px;
  border-radius: var(--radius-sm);
  background: var(--bg);
  transition: all var(--transition);
}

.class-item.active {
  background: var(--primary-light);
  font-weight: 600;
  color: var(--primary-dark);
  border: 1px solid var(--primary);
}

.class-item .class-range {
  color: var(--text-muted);
  font-size: 12px;
  font-weight: 400;
}

.class-item.active .class-range {
  color: var(--primary);
}

/* Trend Chart */
.card-trend { grid-column: span 6; }

.chart-wrap {
  height: 180px;
  position: relative;
}

.trend-svg {
  width: 100%;
  height: 100%;
}

.tooltip {
  position: absolute;
  background: var(--text);
  color: #fff;
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  font-size: 12px;
  pointer-events: none;
  opacity: 0;
  transition: opacity var(--transition);
  z-index: 10;
  white-space: nowrap;
}

/* Entry Card */
.card-entry { grid-column: span 5; }

.entry-tabs {
  display: flex;
  gap: 4px;
  background: var(--bg);
  padding: 4px;
  border-radius: var(--radius-sm);
  margin-bottom: 14px;
}

.tab-btn {
  flex: 1;
  padding: 6px 12px;
  border: none;
  background: transparent;
  font-size: 12px;
  font-weight: 500;
  font-family: var(--font);
  cursor: pointer;
  border-radius: 4px;
  color: var(--text-secondary);
  transition: all var(--transition);
}

.tab-btn.active {
  background: var(--bg-card);
  color: var(--text);
  box-shadow: var(--shadow);
}

.entry-panel {
  display: none;
  flex-direction: column;
  gap: 12px;
}

.entry-panel.active { display: flex; }

.entry-hint {
  font-size: 12px;
  color: var(--text-secondary);
}

textarea, input[type="text"], input[type="number"] {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 8px 10px;
  font-size: 13px;
  font-family: var(--font);
  color: var(--text);
  outline: none;
  transition: border-color var(--transition);
}

textarea:focus, input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-light);
}

textarea {
  resize: vertical;
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 12px;
  min-height: 80px;
}

.manual-form {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.form-group label {
  font-size: 12px;
  font-weight: 500;
  color: var(--text-secondary);
}

/* Courses Card */
.card-courses { grid-column: span 7; }

.card-courses .card-header {
  margin-bottom: 0;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border-light);
}

.filter-group select {
  padding: 5px 24px 5px 8px;
  font-size: 12px;
}

.courses-container {
  max-height: 300px;
  overflow-y: auto;
  margin-top: 12px;
}

.semester-section {
  margin-bottom: 16px;
}

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

.semester-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
}

.semester-title {
  font-size: 14px;
  font-weight: 600;
}

.semester-stats {
  font-size: 12px;
  color: var(--text-secondary);
}

.semester-stats .gpa-value {
  font-weight: 600;
  color: var(--primary);
}

.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 8px;
}

.course-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 12px;
  background: var(--bg);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
  transition: border-color var(--transition);
}

.course-row:hover {
  border-color: var(--border);
}

.course-info {
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.course-code {
  font-size: 13px;
  font-weight: 600;
}

.course-credits {
  font-size: 11px;
  color: var(--text-muted);
}

.course-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.grade-badge {
  font-size: 11px;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 4px;
  text-align: center;
  min-width: 28px;
}

.grade-a { background: var(--success-light); color: var(--success); }
.grade-b { background: var(--primary-light); color: var(--primary); }
.grade-c { background: var(--purple-light); color: var(--purple); }
.grade-d { background: var(--warning-light); color: var(--warning); }
.grade-e { background: #fef3c7; color: var(--warning); }
.grade-f { background: var(--danger-light); color: var(--danger); }
.grade-distinction { background: var(--success-light); color: var(--success); }
.grade-merit { background: var(--primary-light); color: var(--primary); }
.grade-pass { background: var(--warning-light); color: var(--warning); }

.delete-btn {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-muted);
  padding: 4px;
  border-radius: 4px;
  opacity: 0;
  transition: all var(--transition);
}

.course-row:hover .delete-btn { opacity: 1; }

.delete-btn:hover { color: var(--danger); }

.delete-btn i { width: 14px; height: 14px; }

.empty-state {
  text-align: center;
  padding: 40px 20px;
  color: var(--text-muted);
  font-size: 13px;
}

/* Advisor Card */
.card-advisor { grid-column: span 5; }

.advisor-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 12px;
}

.advisor-stat {
  background: var(--bg);
  border-radius: var(--radius-sm);
  padding: 10px;
  text-align: center;
}

.advisor-label {
  display: block;
  font-size: 10px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.3px;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.advisor-value {
  font-size: 15px;
  font-weight: 700;
}

.advisor-message {
  display: flex;
  gap: 10px;
  background: var(--bg);
  border-radius: var(--radius-sm);
  padding: 12px;
  align-items: flex-start;
}

.advisor-avatar {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  font-weight: 700;
  flex-shrink: 0;
}

.advisor-message p {
  font-size: 12px;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* What-If Card */
.card-whatif { grid-column: span 7; }

.whatif-body {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.whatif-hint {
  font-size: 12px;
  color: var(--text-secondary);
}

.sim-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.sim-row {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
}

.sim-label {
  color: var(--text-secondary);
}

.sim-value {
  font-weight: 600;
}

input[type="range"] {
  -webkit-appearance: none;
  width: 100%;
  height: 6px;
  background: var(--bg);
  border-radius: 3px;
  outline: none;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--primary);
  cursor: pointer;
  border: 2px solid #fff;
  box-shadow: var(--shadow);
  transition: transform var(--transition);
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}

.sim-result {
  display: flex;
  gap: 12px;
  background: var(--bg);
  border-radius: var(--radius-sm);
  padding: 14px;
}

.sim-result-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sim-result-label {
  font-size: 10px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.3px;
  color: var(--text-muted);
}

.sim-result-value {
  font-size: 18px;
  font-weight: 700;
}

/* Guide Card */
.card-guide { grid-column: span 12; }

.guide-body {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.guide-section h4 {
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text);
}

.guide-section p,
.guide-section li {
  font-size: 12px;
  color: var(--text-secondary);
  line-height: 1.6;
}

.guide-section ul {
  list-style: none;
  padding: 0;
}

.guide-section li {
  padding: 2px 0;
}

.guide-section li strong {
  color: var(--text);
}

.guide-section code {
  background: var(--bg);
  padding: 1px 5px;
  border-radius: 3px;
  font-size: 12px;
  color: var(--primary-dark);
  font-family: 'SF Mono', 'Fira Code', monospace;
}

/* Footer */
.footer {
  text-align: center;
  padding: 32px 0 0;
  margin-top: 32px;
  border-top: 1px solid var(--border-light);
}

.footer p {
  font-size: 12px;
  color: var(--text-muted);
}

/* Responsive */
@media (max-width: 900px) {
  .card-cgpa { grid-column: span 4; }
  .card-summary { grid-column: span 8; }
  .card-progress { grid-column: span 8; }
  .card-classification { grid-column: span 4; }
  .card-trend { grid-column: span 8; }
  .card-entry { grid-column: span 12; }
  .card-courses { grid-column: span 12; }
  .card-advisor { grid-column: span 6; }
  .card-whatif { grid-column: span 6; }
}

@media (max-width: 600px) {
  .app { padding: 12px; }
  .header { flex-direction: column; gap: 12px; align-items: stretch; text-align: center; }
  .header-left { flex-direction: column; align-items: center; gap: 4px; }
  .header-right { justify-content: center; }
  .card-cgpa, .card-summary, .card-progress, .card-classification,
  .card-trend, .card-entry, .card-courses, .card-advisor, .card-whatif,
  .card-guide {
    grid-column: span 12;
  }
  .manual-form { grid-template-columns: 1fr; }
  .main { gap: 12px; }
}