/* Base Styles and Reset */
:root {
  --bg-gradient: linear-gradient(135deg, #0f172a 0%, #1e1b4b 100%);
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --accent-color: #6366f1;
  --glass-bg: rgba(255, 255, 255, 0.05); /* Slight transparency */
  --glass-border: rgba(255, 255, 255, 0.1);
  --glass-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --card-hover-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.2), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --error-color: #ef4444;
  --modal-bg: rgba(0, 0, 0, 0.4);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg-gradient);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  overflow-x: hidden;
  position: relative;
}

/* Header */
header {
  margin-top: 3rem;
  margin-bottom: 2rem;
  text-align: center;
  animation: fadeInDown 0.8s ease-out;
}

h1 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.025em;
  background: linear-gradient(to right, #ffffff, #94a3b8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 0.5rem;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 1rem;
  font-weight: 400;
}

/* Grid Layout */
.clock-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  width: 90%;
  max-width: 1200px;
  padding-bottom: 6rem; /* Space for FAB */
}

/* Glass Card */
.clock-card {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 1.5rem;
  box-shadow: var(--glass-shadow);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
  position: relative;
  overflow: hidden;
  animation: fadeInUp 0.5s ease-out forwards;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 180px;
}

.clock-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(120deg, rgba(255,255,255,0.1), rgba(255,255,255,0));
  opacity: 0;
  transition: opacity 0.3s;
  pointer-events: none;
}

.clock-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--card-hover-shadow);
  border-color: rgba(255, 255, 255, 0.2);
}

.clock-card:hover::before {
  opacity: 1;
}

/* Card Content */
.card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.location-name {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.4;
}

.timezone-offset {
  font-size: 0.875rem;
  color: var(--text-secondary);
  background: rgba(255, 255, 255, 0.1);
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  white-space: nowrap;
}

.time-display {
  font-family: 'JetBrains Mono', monospace;
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
  letter-spacing: -0.05em;
  text-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

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

.delete-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 0.4rem;
  border-radius: 50%;
  transition: background 0.2s, color 0.2s;
  position: absolute;
  top: 1rem;
  right: 1rem;
  opacity: 0; 
  /* Usually simpler to keep the delete button separate/visible on hover */
}

.clock-card:hover .delete-btn {
  opacity: 1;
}

.delete-btn:hover {
  background: rgba(239, 68, 68, 0.2); /* Red tint */
  color: var(--error-color);
}

/* FAB */
.fab {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--accent-color);
  color: white;
  border: none;
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: transform 0.2s, background 0.2s, box-shadow 0.2s;
  z-index: 100;
}

.fab:hover {
  transform: scale(1.1);
  background: #4f46e5;
  box-shadow: 0 6px 16px rgba(99, 102, 241, 0.6);
}

.fab svg {
  width: 28px;
  height: 28px;
}

/* Modal */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  padding: 1rem;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.modal.visible {
  opacity: 1;
  pointer-events: auto;
}

.hidden {
  display: none; /* Fallback for older browsers or initial state */
}

/* Show/hide utility classes override display:none if we use opacity transition */
.modal:not(.visible) {
    pointer-events: none;
}


.modal-content {
  background: #1e293b; 
  width: 100%;
  max-width: 500px;
  border-radius: 16px;
  padding: 1.5rem;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3);
  border: 1px solid rgba(255, 255, 255, 0.1);
  transform: scale(0.95);
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  display: flex;
  flex-direction: column;
  max-height: 80vh;
}

.modal.visible .modal-content {
  transform: scale(1);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}

.modal-header h2 {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text-primary);
}

.icon-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.2rem;
  transition: color 0.2s;
}

.icon-btn:hover {
  color: var(--text-primary);
}

.search-container input {
  width: 100%;
  padding: 0.75rem 1rem;
  border-radius: 8px;
  border: 1px solid var(--glass-border);
  background: rgba(15, 23, 42, 0.6);
  color: var(--text-primary);
  font-size: 1rem;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
  font-family: inherit;
}

.search-container input:focus {
  border-color: var(--accent-color);
  box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

.timezone-list {
  list-style: none;
  margin-top: 1rem;
  overflow-y: auto;
  flex-grow: 1;
  border-top: 1px solid var(--glass-border);
}

.timezone-item {
  padding: 0.75rem 1rem;
  cursor: pointer;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  transition: background 0.2s;
  color: var(--text-secondary);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.timezone-item:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-primary);
}

.timezone-item .region {
  font-size: 0.8rem;
  opacity: 0.7;
}

/* Animations */
@keyframes fadeInDown {
  from { opacity: 0; transform: translateY(-20px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}
::-webkit-scrollbar-track {
  background: rgba(0,0,0,0.1); 
}
::-webkit-scrollbar-thumb {
  background: rgba(255,255,255,0.1); 
  border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
  background: rgba(255,255,255,0.2); 
}