/* ========================================================================
   Face Shape Detector – Design System & Styles
   ======================================================================== */

/* ── Google Font ────────────────────────────────────────────────────────── */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

/* ── CSS Custom Properties (Dark Theme Default) ────────────────────────── */
:root {
  /* Typography */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;

  /* Border radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 50%;

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ── Dark Theme (Default) ──────────────────────────────────────────────── */
[data-theme="dark"] {
  --color-bg-primary: #0a0a1a;
  --color-bg-secondary: rgba(20, 20, 50, 0.6);
  --color-bg-card: rgba(255, 255, 255, 0.05);
  --color-bg-card-hover: rgba(255, 255, 255, 0.08);
  --color-bg-glass: rgba(255, 255, 255, 0.06);
  --color-border: rgba(255, 255, 255, 0.08);
  --color-border-hover: rgba(255, 255, 255, 0.15);

  --color-text-primary: #f0f0f8;
  --color-text-secondary: #a0a0c0;
  --color-text-muted: #606080;

  --color-accent: #6c63ff;
  --color-accent-hover: #7b73ff;
  --color-accent-glow: rgba(108, 99, 255, 0.3);

  --color-success: #4ecdc4;
  --color-warning: #ffd93d;
  --color-danger: #ff6b6b;

  --gradient-bg: linear-gradient(135deg, #0a0a1a 0%, #1a1040 35%, #0d1b2a 65%, #0a0a1a 100%);
  --gradient-accent: linear-gradient(135deg, #6c63ff 0%, #3b82f6 50%, #8b5cf6 100%);
  --gradient-card: linear-gradient(135deg, rgba(255, 255, 255, 0.04) 0%, rgba(255, 255, 255, 0.01) 100%);

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 40px rgba(108, 99, 255, 0.15);
}

/* ── Light Theme ───────────────────────────────────────────────────────── */
[data-theme="light"] {
  --color-bg-primary: #f5f5ff;
  --color-bg-secondary: rgba(255, 255, 255, 0.7);
  --color-bg-card: rgba(255, 255, 255, 0.7);
  --color-bg-card-hover: rgba(255, 255, 255, 0.9);
  --color-bg-glass: rgba(255, 255, 255, 0.5);
  --color-border: rgba(0, 0, 0, 0.08);
  --color-border-hover: rgba(0, 0, 0, 0.15);

  --color-text-primary: #1a1a2e;
  --color-text-secondary: #4a4a6a;
  --color-text-muted: #8a8aaa;

  --color-accent: #5b52e0;
  --color-accent-hover: #4a42d0;
  --color-accent-glow: rgba(91, 82, 224, 0.2);

  --color-success: #2eb8a8;
  --color-warning: #e6c230;
  --color-danger: #e55555;

  --gradient-bg: linear-gradient(135deg, #f5f5ff 0%, #e8e0ff 35%, #e0f0ff 65%, #f5f5ff 100%);
  --gradient-accent: linear-gradient(135deg, #5b52e0 0%, #3b82f6 50%, #7c5ce0 100%);
  --gradient-card: linear-gradient(135deg, rgba(255, 255, 255, 0.8) 0%, rgba(255, 255, 255, 0.4) 100%);

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.1);
  --shadow-glow: 0 0 40px rgba(91, 82, 224, 0.1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-primary);
  background: var(--gradient-bg);
  color: var(--color-text-primary);
  min-height: 100vh;
  line-height: 1.6;
  transition: background var(--transition-slow), color var(--transition-normal);
  overflow-x: hidden;
}

/* Animated background */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    radial-gradient(ellipse 600px 600px at 20% 20%, rgba(108, 99, 255, 0.08) 0%, transparent 70%),
    radial-gradient(ellipse 500px 500px at 80% 80%, rgba(59, 130, 246, 0.06) 0%, transparent 70%),
    radial-gradient(ellipse 400px 400px at 50% 50%, rgba(139, 92, 246, 0.04) 0%, transparent 70%);
  z-index: -1;
  animation: bgPulse 12s ease-in-out infinite alternate;
}

@keyframes bgPulse {
  0% {
    opacity: 0.7;
    transform: scale(1);
  }

  100% {
    opacity: 1;
    transform: scale(1.05);
  }
}

/* ── Utility ───────────────────────────────────────────────────────────── */
.hidden {
  display: none !important;
}

/* ── Layout ────────────────────────────────────────────────────────────── */
.app-container {
  max-width: 960px;
  margin: 0 auto;
  padding: var(--space-md);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ── Header ────────────────────────────────────────────────────────────── */
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-lg) 0;
  gap: var(--space-md);
}

.header a {
  color: var(--color-text-primary);
  text-decoration: none;
  font-weight: 600;
  transition: color var(--transition-fast);
}

.header a:hover {
  color: var(--color-accent);
}

.header-brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.header-logo {
  font-size: 1.8rem;
  line-height: 1;
}

.header-title {
  font-size: 1.35rem;
  font-weight: 700;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
}

.header-subtitle {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  font-weight: 400;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.theme-toggle {
  background: var(--color-bg-glass);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  width: 42px;
  height: 42px;
  display: grid;
  padding-right: 10px;
  margin: auto 10px;
  place-items: center;
  cursor: pointer;
  font-size: 1.2rem;
  transition: all var(--transition-normal);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.theme-toggle:hover {
  background: var(--color-bg-card-hover);
  border-color: var(--color-border-hover);
  transform: rotate(20deg) scale(1.05);
}

/* ── Main Content ──────────────────────────────────────────────────────── */
.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: var(--space-xl);
}

/* ── Upload Zone ───────────────────────────────────────────────────────── */
.upload-zone {
  background: var(--gradient-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 2px dashed var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-2xl) var(--space-xl);
  text-align: center;
  transition: all var(--transition-normal);
  cursor: default;
}

.upload-zone.drag-over {
  border-color: var(--color-accent);
  background: rgba(108, 99, 255, 0.05);
  box-shadow: var(--shadow-glow);
  transform: scale(1.01);
}

.upload-icon {
  font-size: 3.5rem;
  margin-bottom: var(--space-md);
  display: block;
  animation: float 3s ease-in-out infinite;
}

@keyframes float {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-8px);
  }
}

.upload-title {
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: var(--space-xs);
  color: var(--color-text-primary);
}

.upload-subtitle {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-lg);
}

.upload-actions {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  flex-wrap: wrap;
}

/* ── Buttons ───────────────────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.7rem 1.4rem;
  border: none;
  border-radius: var(--radius-md);
  font-family: var(--font-primary);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-normal);
  text-decoration: none;
  line-height: 1.2;
  white-space: nowrap;
}

.btn-primary {
  background: var(--gradient-accent);
  color: #fff;
  box-shadow: var(--shadow-sm), 0 0 20px var(--color-accent-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md), 0 0 30px var(--color-accent-glow);
}

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

.btn-secondary {
  background: var(--color-bg-glass);
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: var(--color-bg-card-hover);
  border-color: var(--color-border-hover);
  transform: translateY(-2px);
}

.btn-icon {
  font-size: 1.1rem;
}

/* ── Status Bar ────────────────────────────────────────────────────────── */
.status-bar {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background: var(--color-bg-glass);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.status-dot {
  width: 6px;
  height: 6px;
  border-radius: var(--radius-full);
  background: var(--color-success);
  animation: pulse 2s infinite;
}

@keyframes pulse {

  0%,
  100% {
    opacity: 1;
  }

  50% {
    opacity: 0.4;
  }
}

/* ── Display Section ───────────────────────────────────────────────────── */
.display-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.canvas-wrapper {
  position: relative;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

.canvas-wrapper img,
.canvas-wrapper video {
  display: block;
  width: 100%;
  height: auto;
  max-height: 520px;
  object-fit: contain;
  background: #000;
}

.canvas-wrapper canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.display-controls {
  display: flex;
  gap: var(--space-sm);
  justify-content: center;
  flex-wrap: wrap;
}

/* ── Error Message ─────────────────────────────────────────────────────── */
.error-message {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md) var(--space-lg);
  background: rgba(255, 107, 107, 0.08);
  border: 1px solid rgba(255, 107, 107, 0.2);
  border-radius: var(--radius-md);
  color: var(--color-danger);
  font-size: 0.85rem;
  animation: slideDown 0.3s ease;
}

.error-message .error-icon {
  font-size: 1.2rem;
  flex-shrink: 0;
}

.error-message .error-text {
  flex: 1;
}

.error-message .error-dismiss {
  background: none;
  border: none;
  color: var(--color-danger);
  cursor: pointer;
  font-size: 1.2rem;
  padding: 0;
  opacity: 0.7;
  transition: opacity var(--transition-fast);
  flex-shrink: 0;
}

.error-message .error-dismiss:hover {
  opacity: 1;
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ── Result Card ───────────────────────────────────────────────────────── */
.result-card {
  background: var(--gradient-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  box-shadow: var(--shadow-lg), var(--shadow-glow);
  opacity: 0;
  transform: translateY(20px);
}

.result-card.animate-in {
  animation: resultReveal 0.6s var(--transition-slow) forwards;
}

@keyframes resultReveal {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.result-header {
  text-align: center;
  margin-bottom: var(--space-lg);
}

.result-label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--color-text-muted);
  font-weight: 600;
  margin-bottom: var(--space-xs);
}

.result-shape {
  font-size: 2rem;
  font-weight: 800;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
}

/* ── Confidence ────────────────────────────────────────────────────────── */
.confidence-section {
  margin-bottom: var(--space-lg);
}

.confidence-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-xs);
}

.confidence-label {
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  font-weight: 500;
}

.confidence-value {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--color-accent);
}

.confidence-track {
  width: 100%;
  height: 6px;
  background: var(--color-bg-card);
  border-radius: 3px;
  overflow: hidden;
  border: 1px solid var(--color-border);
}

.confidence-bar {
  height: 100%;
  background: var(--gradient-accent);
  border-radius: 3px;
  width: 0%;
  transition: width 1s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ── Description ───────────────────────────────────────────────────────── */
.result-description {
  font-size: 0.88rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
  text-align: center;
  margin-bottom: var(--space-lg);
  padding: 0 var(--space-md);
}

/* ── Ratios Grid ───────────────────────────────────────────────────────── */
.ratios-section-title {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--color-text-muted);
  font-weight: 600;
  margin-bottom: var(--space-md);
  text-align: center;
}

.ratios-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: var(--space-sm);
}

.ratio-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-sm) var(--space-md);
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.ratio-item:hover {
  background: var(--color-bg-card-hover);
  border-color: var(--color-border-hover);
}

.ratio-label {
  font-size: 0.75rem;
  color: var(--color-text-secondary);
  font-weight: 500;
}

.ratio-value {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--color-accent);
  font-variant-numeric: tabular-nums;
}

/* ── SEO Content Section ──────────────────────────────────────────────── */
.seo-section {
  background: var(--gradient-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-2xl) var(--space-xl);
  margin-top: var(--space-xl);
  box-shadow: var(--shadow-lg), var(--shadow-glow);
  color: var(--color-text-secondary);
}

.seo-section h2 {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--color-text-primary);
  margin-top: var(--space-xl);
  margin-bottom: var(--space-md);
  line-height: 1.3;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.seo-section h2:first-child {
  margin-top: 0;
}

.seo-section h3 {
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-top: var(--space-lg);
  margin-bottom: var(--space-sm);
}

.seo-section p {
  margin-bottom: var(--space-md);
  line-height: 1.8;
  font-size: 1.05rem;
}

.seo-section ul {
  margin-bottom: var(--space-lg);
  padding-left: var(--space-xl);
}

.seo-section li {
  margin-bottom: var(--space-sm);
  line-height: 1.7;
  font-size: 1.05rem;
}

.seo-section strong {
  color: var(--color-text-primary);
}

.seo-section code {
  background: rgba(0, 0, 0, 0.2);
  padding: 0.2rem 0.4rem;
  border-radius: var(--radius-sm);
  font-family: monospace;
  font-size: 0.9em;
}

[data-theme="light"] .seo-section code {
  background: rgba(0, 0, 0, 0.05);
}

/* ── Loading Overlay ───────────────────────────────────────────────────── */
.loading-overlay {
  position: fixed;
  inset: 0;
  background: rgba(10, 10, 26, 0.92);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  gap: var(--space-lg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.spinner {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-full);
  border: 3px solid var(--color-border);
  border-top-color: var(--color-accent);
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.loading-text {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  font-weight: 500;
  letter-spacing: 0.02em;
}

/* ── Footer ────────────────────────────────────────────────────────────── */
.footer {
  text-align: center;
  padding: var(--space-xl) 0 var(--space-lg);
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

.footer a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer a:hover {
  color: var(--color-accent-hover);
}

/* ── Responsive ────────────────────────────────────────────────────────── */
@media (max-width: 640px) {
  .app-container {
    padding: var(--space-sm);
  }

  .header {
    padding: var(--space-md) 0;
  }

  .header-title {
    font-size: 1.1rem;
  }

  .header-subtitle {
    display: none;
  }

  .upload-zone {
    padding: var(--space-xl) var(--space-md);
  }

  .upload-icon {
    font-size: 2.5rem;
  }

  .upload-title {
    font-size: 1rem;
  }

  .upload-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .btn {
    justify-content: center;
  }

  .result-card {
    padding: var(--space-lg);
  }

  .result-shape {
    font-size: 1.5rem;
  }

  .ratios-grid {
    grid-template-columns: 1fr;
  }

  .canvas-wrapper img,
  .canvas-wrapper video {
    max-height: 360px;
  }
}

@media (max-width: 380px) {
  .header-brand {
    gap: var(--space-xs);
  }

  .header-logo {
    font-size: 1.4rem;
  }

  .header-title {
    font-size: 0.95rem;
  }
}

/* ── Print ─────────────────────────────────────────────────────────────── */
@media print {

  body::before,
  .loading-overlay,
  .upload-zone,
  .display-controls,
  .status-bar,
  .theme-toggle {
    display: none !important;
  }
}