/* Design Tokens & Theme Setup */
:root {
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  
  /* Light Theme Palette (Default) */
  --color-bg: #f8fafc;
  --color-card-bg: #ffffff;
  --color-border: #e2e8f0;
  --color-text-primary: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #94a3b8;
  
  /* Buttons & Controls */
  --color-btn-primary-bg: #0f172a;
  --color-btn-primary-text: #ffffff;
  --color-btn-primary-hover: #1e293b;
  
  --color-btn-secondary-bg: #f1f5f9;
  --color-btn-secondary-border: #e2e8f0;
  --color-btn-secondary-text: #475569;
  --color-btn-secondary-hover: #e2e8f0;

  --color-input-bg: #ffffff;
  --color-input-border: #cbd5e1;
  --color-input-focus-border: #0f172a;
  --color-focus-ring: 0 0 0 3px rgba(15, 23, 42, 0.08);
  
  /* Status Colors */
  --color-accent: #2563eb;
  --color-accent-subtle: #eff6ff;
  --color-error-bg: #fef2f2;
  --color-error-border: #fee2e2;
  --color-error-text: #b91c1c;
  --color-success: #10b981;
  
  /* Shadows & Layout */
  --card-shadow: 0 1px 3px rgba(0, 0, 0, 0.05), 
                 0 10px 15px -3px rgba(0, 0, 0, 0.03), 
                 0 4px 6px -2px rgba(0, 0, 0, 0.02),
                 0 0 0 1px rgba(0, 0, 0, 0.02);
  --dialog-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.08), 
                   0 10px 10px -5px rgba(0, 0, 0, 0.03),
                   0 0 0 1px rgba(0, 0, 0, 0.04);
  --border-radius-lg: 16px;
  --border-radius-md: 10px;
}

/* System Dark Theme Overrides */
@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #090d16;
    --color-card-bg: #111827;
    --color-border: #1f2937;
    --color-text-primary: #f9fafb;
    --color-text-secondary: #9ca3af;
    --color-text-muted: #6b7280;
    
    --color-btn-primary-bg: #f9fafb;
    --color-btn-primary-text: #111827;
    --color-btn-primary-hover: #e5e7eb;
    
    --color-btn-secondary-bg: #1f2937;
    --color-btn-secondary-border: #374151;
    --color-btn-secondary-text: #d1d5db;
    --color-btn-secondary-hover: #374151;

    --color-input-bg: #1f2937;
    --color-input-border: #374151;
    --color-input-focus-border: #f9fafb;
    --color-focus-ring: 0 0 0 3px rgba(249, 250, 251, 0.1);
    
    --color-accent: #3b82f6;
    --color-accent-subtle: #172554;
    --color-error-bg: rgba(239, 68, 68, 0.1);
    --color-error-border: rgba(239, 68, 68, 0.2);
    --color-error-text: #fca5a5;
    
    --card-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 
                   0 4px 6px -2px rgba(0, 0, 0, 0.2),
                   0 0 0 1px rgba(255, 255, 255, 0.03);
    --dialog-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5),
                     0 0 0 1px rgba(255, 255, 255, 0.05);
  }
}

/* Base resets & layout */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-primary);
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow-x: hidden;
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* Wrapper container */
.app-container {
  width: 100%;
  max-width: 440px;
  padding: 1.5rem;
  position: relative;
}

/* Settings button inside card */
.settings-btn {
  position: absolute;
  top: 1.25rem;
  right: 1.25rem;
  background: transparent;
  border: none;
  border-radius: 8px;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
  cursor: pointer;
  transition: all 0.15s ease;
}

.settings-btn svg {
  width: 18px;
  height: 18px;
  transition: transform 0.3s ease;
}

.settings-btn:hover {
  color: var(--color-text-primary);
  background: var(--color-btn-secondary-bg);
}

.settings-btn:hover svg {
  transform: rotate(30deg);
}

.settings-btn:focus-visible {
  outline: none;
  box-shadow: var(--color-focus-ring);
}

/* Minimalist main weather card */
.weather-card {
  position: relative;
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-lg);
  padding: 2.25rem 2rem;
  box-shadow: var(--card-shadow);
  text-align: center;
  transition: background-color 0.3s ease, border-color 0.3s ease;
}

.weather-card h1 {
  font-size: 1.6rem;
  font-weight: 700;
  margin-bottom: 1.75rem;
  letter-spacing: -0.5px;
  color: var(--color-text-primary);
}

/* Search Form */
#weatherForm {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.input-group {
  display: flex;
  gap: 0.5rem;
  width: 100%;
}

#cityInput {
  flex: 1;
  background: var(--color-input-bg);
  border: 1px solid var(--color-input-border);
  border-radius: var(--border-radius-md);
  padding: 0.75rem 1rem;
  color: var(--color-text-primary);
  font-family: inherit;
  font-size: 0.95rem;
  transition: all 0.2s ease;
  min-width: 0;
}

#cityInput::placeholder {
  color: var(--color-text-muted);
}

#cityInput:focus {
  outline: none;
  border-color: var(--color-input-focus-border);
  box-shadow: var(--color-focus-ring);
}

#weatherForm button[type="submit"] {
  background: var(--color-btn-primary-bg);
  color: var(--color-btn-primary-text);
  border: none;
  border-radius: var(--border-radius-md);
  padding: 0.75rem 1.25rem;
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

#weatherForm button[type="submit"]:hover {
  background: var(--color-btn-primary-hover);
}

#weatherForm button[type="submit"]:focus-visible {
  outline: none;
  box-shadow: var(--color-focus-ring);
}

/* Weather Output Container */
.weather-data-container {
  margin-top: 1rem;
  min-height: 80px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

/* Result Layout */
.weather-result {
  animation: fade-in 0.3s ease-out forwards;
}

@keyframes fade-in {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

.weather-header {
  margin-bottom: 0.25rem;
}

.weather-city {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--color-text-primary);
}

.weather-country {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--color-text-muted);
  font-weight: 600;
  margin-top: 0.15rem;
}

.weather-main {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.25rem;
  margin: 1.25rem 0;
  padding: 0.75rem;
  background: var(--color-bg);
  border-radius: var(--border-radius-md);
  border: 1px solid var(--color-border);
}

.weather-icon-box {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.weather-icon-img {
  width: 52px;
  height: 52px;
  object-fit: contain;
}

.weather-temp-box {
  text-align: left;
}

.weather-temp-value {
  font-size: 2.25rem;
  font-weight: 700;
  line-height: 1;
  color: var(--color-text-primary);
}

.weather-temp-unit {
  font-size: 1.1rem;
  vertical-align: super;
  font-weight: 600;
  color: var(--color-text-secondary);
}

.weather-details {
  border-radius: var(--border-radius-md);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  margin-top: 1rem;
}

.weather-detail-item {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-md);
  padding: 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.weather-detail-label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--color-text-muted);
  font-weight: 600;
}

.weather-detail-value {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text-primary);
}

/* Error and prompt states */
.weather-error {
  background: var(--color-error-bg);
  border: 1px solid var(--color-error-border);
  border-radius: var(--border-radius-md);
  padding: 1rem;
  color: var(--color-error-text);
  font-size: 0.9rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  align-items: center;
}

.weather-error-title {
  font-weight: 700;
  font-size: 0.95rem;
}

.weather-prompt {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  line-height: 1.5;
  padding: 0.5rem;
}

.weather-prompt button {
  background: none;
  border: none;
  color: var(--color-accent);
  text-decoration: underline;
  font-family: inherit;
  font-size: inherit;
  cursor: pointer;
  font-weight: 500;
  padding: 0;
}

.weather-prompt button:hover {
  color: var(--color-text-primary);
}

/* Professional Settings Dialog */
dialog.settings-dialog {
  position: fixed;
  top: 50%;
  left: 50%;
  translate: -50% -50%;
  border: 1px solid var(--color-border);
  background: var(--color-card-bg);
  color: var(--color-text-primary);
  border-radius: var(--border-radius-lg);
  padding: 2rem;
  max-width: 400px;
  width: calc(100% - 2rem);
  box-shadow: var(--dialog-shadow);
  opacity: 0;
  transform: scale(0.96);
  transition: opacity 0.2s ease, 
              transform 0.2s cubic-bezier(0.16, 1, 0.3, 1), 
              display 0.2s ease allow-discrete;
}

dialog.settings-dialog[open] {
  opacity: 1;
  transform: scale(1);
}

@starting-style {
  dialog.settings-dialog[open] {
    opacity: 0;
    transform: scale(0.96);
  }
}

dialog.settings-dialog::backdrop {
  background: rgba(15, 23, 42, 0.3);
  backdrop-filter: blur(4px);
  opacity: 0;
  transition: opacity 0.2s ease, backdrop-filter 0.2s ease, display 0.2s ease allow-discrete;
}

@media (prefers-color-scheme: dark) {
  dialog.settings-dialog::backdrop {
    background: rgba(3, 7, 18, 0.6);
  }
}

dialog.settings-dialog[open]::backdrop {
  opacity: 1;
}

@starting-style {
  dialog.settings-dialog[open]::backdrop {
    opacity: 0;
  }
}

.dialog-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.dialog-header h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text-primary);
}

.close-btn {
  background: none;
  border: none;
  color: var(--color-text-secondary);
  font-size: 1.5rem;
  cursor: pointer;
  line-height: 1;
  transition: color 0.15s ease;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
}

.close-btn:hover {
  color: var(--color-text-primary);
  background: var(--color-btn-secondary-bg);
}

.close-btn:focus-visible {
  outline: none;
  box-shadow: var(--color-focus-ring);
}

.dialog-body p {
  color: var(--color-text-secondary);
  font-size: 0.85rem;
  line-height: 1.45;
  margin-bottom: 1.25rem;
}

.dialog-body a {
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 500;
}

.dialog-body a:hover {
  text-decoration: underline;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  margin-bottom: 1.5rem;
}

.form-group label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-text-secondary);
}

#apiKeyInput {
  background: var(--color-input-bg);
  border: 1px solid var(--color-input-border);
  border-radius: var(--border-radius-md);
  padding: 0.7rem 0.9rem;
  color: var(--color-text-primary);
  font-family: inherit;
  font-size: 0.9rem;
  transition: all 0.2s ease;
}

#apiKeyInput:focus {
  outline: none;
  border-color: var(--color-input-focus-border);
  box-shadow: var(--color-focus-ring);
}

.dialog-actions {
  display: flex;
  justify-content: flex-end;
  gap: 0.5rem;
}

.btn {
  padding: 0.65rem 1.1rem;
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: var(--border-radius-md);
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-secondary {
  background: var(--color-btn-secondary-bg);
  color: var(--color-btn-secondary-text);
  border: 1px solid var(--color-btn-secondary-border);
}

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

.btn-primary {
  background: var(--color-btn-primary-bg);
  color: var(--color-btn-primary-text);
  border: none;
}

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

.btn:focus-visible {
  outline: none;
  box-shadow: var(--color-focus-ring);
}

/* Minimalist Toast Alerts */
.toast-msg {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%) translateY(10px);
  background: var(--color-btn-primary-bg);
  color: var(--color-btn-primary-text);
  padding: 0.6rem 1.2rem;
  border-radius: 30px;
  font-weight: 500;
  font-size: 0.85rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  opacity: 0;
  pointer-events: none;
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  z-index: 1000;
  border: 1px solid var(--color-border);
}

.toast-msg.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* Mobile Responsiveness styling */
@media (max-width: 480px) {
  .weather-card {
    padding: 1.75rem 1.25rem;
  }
  
  .input-group {
    flex-direction: column;
    gap: 0.5rem;
  }
  
  #cityInput, #weatherForm button[type="submit"] {
    width: 100%;
    text-align: center;
  }
}