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

:root {
  --primary: #4285f4;
  --primary-dark: #3367d6;
  --danger: #ea4335;
  --success: #34a853;
  --warning: #fbbc04;
  --bg: #f8f9fa;
  --card-bg: #ffffff;
  --text: #202124;
  --text-secondary: #5f6368;
  --border: #e0e0e0;
  --radius: 12px;
  --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);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px;
}

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

header h1 {
  font-size: 1.8rem;
  color: var(--primary);
  margin-bottom: 4px;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* Child nav */
.child-nav {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-top: 12px;
  flex-wrap: wrap;
}

.child-nav a {
  display: inline-block;
  padding: 6px 16px;
  border-radius: 20px;
  text-decoration: none;
  color: var(--text-secondary);
  background: var(--card-bg);
  border: 1px solid var(--border);
  font-size: 0.9rem;
  transition: all 0.2s;
}

.child-nav a.active {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

.child-nav a:hover:not(.active) {
  border-color: var(--primary);
  color: var(--primary);
}

.btn-add {
  background: var(--success) !important;
  color: white !important;
  border-color: var(--success) !important;
}

/* Child info */
.child-info {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
  padding: 12px 0;
}

.child-info h2 {
  font-size: 1.3rem;
}

.birth-date {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

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

.card h3 {
  font-size: 1.05rem;
  margin-bottom: 14px;
  color: var(--text);
}

/* Charts */
.charts-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.chart-card {
  min-height: 360px;
}

.chart-wrapper {
  position: relative;
  height: 300px;
}

/* Filter */
.filter-card {
  background: linear-gradient(135deg, #e8f0fe, #f0f4ff);
}

.filter-row {
  display: flex;
  gap: 16px;
  align-items: flex-end;
  flex-wrap: wrap;
}

.quick-filters {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.btn-sm {
  padding: 4px 12px;
  border: 1px solid var(--border);
  background: var(--card-bg);
  border-radius: 16px;
  cursor: pointer;
  font-size: 0.82rem;
  transition: all 0.2s;
}

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

/* Analysis */
.analysis-card {
  background: linear-gradient(135deg, #fef7e0, #fff8e8);
  border-left: 4px solid var(--warning);
}

.analysis-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.analysis-item {
  display: flex;
  flex-direction: column;
}

.analysis-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.analysis-value {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text);
}

.analysis-detail {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.trend-up { color: var(--success); }
.trend-down { color: var(--danger); }
.trend-stable { color: var(--text-secondary); }

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

.form-group label {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.form-group input, .form-group select {
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.95rem;
  transition: border-color 0.2s;
}

.form-group input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(66, 133, 244, 0.15);
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 12px;
  margin-bottom: 14px;
}

.measurement-form {
  max-width: 100%;
}

/* Buttons */
.btn {
  padding: 10px 24px;
  border: none;
  border-radius: 8px;
  font-size: 0.95rem;
  cursor: pointer;
  font-weight: 500;
  transition: all 0.2s;
}

.btn-primary {
  background: var(--primary);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-dark);
  box-shadow: var(--shadow-lg);
}

.btn-danger-sm {
  background: none;
  border: none;
  color: var(--danger);
  cursor: pointer;
  font-size: 0.85rem;
  padding: 2px 6px;
  opacity: 0.6;
  transition: opacity 0.2s;
}

.btn-danger-sm:hover {
  opacity: 1;
}

.inline-form {
  display: inline;
}

/* Table */
.table-responsive {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

thead th {
  background: var(--bg);
  padding: 10px 12px;
  text-align: left;
  font-weight: 600;
  color: var(--text-secondary);
  border-bottom: 2px solid var(--border);
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.3px;
}

tbody td {
  padding: 10px 12px;
  border-bottom: 1px solid var(--border);
}

tbody tr:hover {
  background: rgba(66, 133, 244, 0.04);
}

.empty-state {
  color: var(--text-secondary);
  text-align: center;
  padding: 24px;
}

/* Footer */
footer {
  text-align: center;
  padding: 24px 0;
  color: var(--text-secondary);
  font-size: 0.8rem;
}

/* Login */
.login-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 60vh;
}

.login-card {
  max-width: 360px;
  width: 100%;
  text-align: center;
}

.login-card h1 {
  color: var(--primary);
  margin-bottom: 4px;
}

.login-card .subtitle {
  margin-bottom: 20px;
}

.login-card .form-group {
  margin-bottom: 14px;
}

.login-card input[type="password"] {
  width: 100%;
  padding: 12px;
  font-size: 1.1rem;
  text-align: center;
}

.btn-full {
  width: 100%;
}

.error-msg {
  background: #fce8e6;
  color: var(--danger);
  padding: 8px 12px;
  border-radius: 8px;
  margin-bottom: 14px;
  font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
  .charts-grid {
    grid-template-columns: 1fr;
  }

  .filter-row {
    flex-direction: column;
    align-items: stretch;
  }

  .form-row {
    grid-template-columns: 1fr 1fr;
  }

  .child-info {
    flex-wrap: wrap;
  }

  header h1 {
    font-size: 1.4rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 12px;
  }

  .form-row {
    grid-template-columns: 1fr;
  }
}