:root {
  --primary: #0284c7;
  --primary-dark: #0369a1;
  --primary-light: #e0f2fe;
  --accent: #10b981;
  --danger: #ef4444;
  --warning: #f59e0b;
  --dark: #0f172a;
  --slate: #475569;
  --light: #f8fafc;
  --border: #e2e8f0;
  --radius: 16px;
  --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

body {
  background: #f1f5f9;
  color: var(--dark);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
.app-header {
  background: linear-gradient(135deg, #0284c7 0%, #0369a1 100%);
  color: #fff;
  padding: 16px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 4px 20px rgba(2, 132, 199, 0.15);
}

.brand-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: #fff;
}

.brand-icon {
  width: 44px;
  height: 44px;
  background: rgba(255, 255, 255, 0.2);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
}

.brand-title {
  font-size: 1.15rem;
  font-weight: 800;
  letter-spacing: -0.3px;
}

.brand-sub {
  font-size: 0.8rem;
  opacity: 0.85;
}

.nav-btn {
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.25);
  color: #fff;
  padding: 8px 16px;
  border-radius: 10px;
  font-size: 0.85rem;
  font-weight: 700;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all 0.2s;
  cursor: pointer;
}

.nav-btn:hover {
  background: rgba(255, 255, 255, 0.25);
}

/* Container */
.container {
  max-width: 960px;
  margin: 30px auto;
  padding: 0 20px;
  flex: 1;
  width: 100%;
}

.card {
  background: #fff;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  padding: 28px;
  margin-bottom: 24px;
}

.card-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--dark);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.card-desc {
  font-size: 0.88rem;
  color: var(--slate);
  margin-bottom: 20px;
  line-height: 1.5;
}

/* Forms */
.form-group {
  margin-bottom: 18px;
}

.form-label {
  display: block;
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 6px;
}

.form-control {
  width: 100%;
  padding: 12px 16px;
  border-radius: 12px;
  border: 1.5px solid var(--border);
  font-size: 0.95rem;
  outline: none;
  transition: all 0.2s;
  background: #fff;
}

.form-control:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.15);
}

/* Checkin Action Buttons */
.check-btn-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin: 24px 0;
}

.btn-check {
  padding: 20px 16px;
  border-radius: 16px;
  border: none;
  color: #fff;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: transform 0.15s, box-shadow 0.15s;
  font-weight: 800;
  font-size: 1.1rem;
}

.btn-check:hover {
  transform: translateY(-2px);
}

.btn-check:active {
  transform: translateY(0);
}

.btn-check-in {
  background: linear-gradient(135deg, #10b981 0%, #059669 100%);
  box-shadow: 0 8px 20px rgba(16, 185, 129, 0.25);
}

.btn-check-out {
  background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
  box-shadow: 0 8px 20px rgba(245, 158, 11, 0.25);
}

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 4px 10px;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 700;
}

.badge-success { background: #dcfce7; color: #15803d; }
.badge-warning { background: #fef3c7; color: #b45309; }
.badge-danger { background: #fee2e2; color: #b91c1c; }
.badge-info { background: #e0f2fe; color: #0369a1; }

/* History Table */
.custom-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

.custom-table th {
  background: #f8fafc;
  padding: 12px 16px;
  text-align: left;
  font-weight: 800;
  color: var(--slate);
  border-bottom: 2px solid var(--border);
}

.custom-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}

/* Digital Clock */
.clock-display {
  text-align: center;
  padding: 20px;
  background: #f8fafc;
  border-radius: 14px;
  border: 1px dashed var(--border);
  margin-bottom: 20px;
}

.clock-time {
  font-size: 2.4rem;
  font-weight: 900;
  color: var(--dark);
  letter-spacing: 1px;
}

.clock-date {
  font-size: 0.9rem;
  color: var(--slate);
  margin-top: 4px;
}

@media (max-width: 640px) {
  .check-btn-grid {
    grid-template-columns: 1fr;
  }
}