/**
 * ShapeEd Studio - Unified Design System
 * Professional, Clean, Minimal
 * Updated: January 30, 2026
 */

/* ================================== */
/* DESIGN TOKENS */
/* ================================== */
:root {
  /* Color Palette - Professional & Clean */
  --primary: #1e293b;           /* Slate 800 - Primary text/buttons */
  --primary-hover: #334155;     /* Slate 700 */
  --primary-light: #475569;     /* Slate 600 */
  
  --accent: #3b82f6;            /* Blue 500 - Links, highlights */
  --accent-hover: #2563eb;      /* Blue 600 */
  --accent-light: #60a5fa;      /* Blue 400 */
  
  --success: #10b981;           /* Emerald 500 */
  --warning: #f59e0b;           /* Amber 500 */
  --error: #ef4444;             /* Red 500 */
  --info: #06b6d4;              /* Cyan 500 */
  
  /* Neutrals */
  --gray-50: #f8fafc;
  --gray-100: #f1f5f9;
  --gray-200: #e2e8f0;
  --gray-300: #cbd5e1;
  --gray-400: #94a3b8;
  --gray-500: #64748b;
  --gray-600: #475569;
  --gray-700: #334155;
  --gray-800: #1e293b;
  --gray-900: #0f172a;
  
  --white: #ffffff;
  --black: #000000;
  
  /* Semantic Colors */
  --text-primary: var(--gray-900);
  --text-secondary: var(--gray-600);
  --text-muted: var(--gray-500);
  --text-disabled: var(--gray-400);
  
  --bg-primary: var(--white);
  --bg-secondary: var(--gray-50);
  --bg-tertiary: var(--gray-100);
  
  --border-light: var(--gray-200);
  --border-medium: var(--gray-300);
  --border-dark: var(--gray-400);
  
  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  --font-mono: 'SF Mono', 'Monaco', 'Cascadia Code', 'Courier New', monospace;
  
  --text-xs: 0.75rem;      /* 12px */
  --text-sm: 0.875rem;     /* 14px */
  --text-base: 1rem;       /* 16px */
  --text-lg: 1.125rem;     /* 18px */
  --text-xl: 1.25rem;      /* 20px */
  --text-2xl: 1.5rem;      /* 24px */
  --text-3xl: 1.875rem;    /* 30px */
  --text-4xl: 2.25rem;     /* 36px */
  
  --weight-normal: 400;
  --weight-medium: 500;
  --weight-semibold: 600;
  --weight-bold: 700;
  
  --line-tight: 1.25;
  --line-normal: 1.5;
  --line-relaxed: 1.75;
  
  /* Spacing Scale */
  --space-1: 0.25rem;   /* 4px */
  --space-2: 0.5rem;    /* 8px */
  --space-3: 0.75rem;   /* 12px */
  --space-4: 1rem;      /* 16px */
  --space-5: 1.25rem;   /* 20px */
  --space-6: 1.5rem;    /* 24px */
  --space-8: 2rem;      /* 32px */
  --space-10: 2.5rem;   /* 40px */
  --space-12: 3rem;     /* 48px */
  --space-16: 4rem;     /* 64px */
  --space-20: 5rem;     /* 80px */
  
  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Z-index */
  --z-base: 0;
  --z-dropdown: 100;
  --z-sticky: 500;
  --z-modal-backdrop: 1000;
  --z-modal: 1100;
  --z-toast: 1200;
}

/* ================================== */
/* BUTTON SYSTEM */
/* ================================== */

/* Base Button */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: var(--weight-medium);
  line-height: var(--line-tight);
  text-align: center;
  text-decoration: none;
  white-space: nowrap;
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  outline: none;
  user-select: none;
}

.btn:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* Button Variants */
.btn--primary {
  background: var(--primary);
  color: var(--white);
  border-color: var(--primary);
}

.btn--primary:hover:not(:disabled) {
  background: var(--primary-hover);
  border-color: var(--primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

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

.btn--secondary:hover:not(:disabled) {
  background: var(--primary);
  border-color: var(--primary);
  color: var(--white);
}

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

.btn--accent:hover:not(:disabled) {
  background: var(--accent-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn--ghost {
  background: transparent;
  color: var(--text-secondary);
  border-color: transparent;
}

.btn--ghost:hover:not(:disabled) {
  background: var(--gray-100);
  color: var(--text-primary);
}

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

.btn--success:hover:not(:disabled) {
  background: #059669;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

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

.btn--danger:hover:not(:disabled) {
  background: #dc2626;
}

/* Button Sizes */
.btn--sm {
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
}

.btn--lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-lg);
}

.btn--full {
  width: 100%;
}

/* Inline Button Variants (for quick use without class combinations) */
.btn-inline-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 16px;
  background: #4f46e5;
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-base);
}

.btn-inline-primary:hover {
  background: #4338ca;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(79, 70, 229, 0.3);
  color: white;
}

.btn-inline-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 16px;
  background: #f1f5f9;
  color: #334155;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-base);
}

.btn-inline-secondary:hover {
  background: #e2e8f0;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  color: #334155;
}

.btn-inline-warning {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 16px;
  background: #fbbf24;
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-base);
}

.btn-inline-warning:hover {
  background: #f59e0b;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(251, 191, 36, 0.3);
  color: white;
}

.btn-inline-upgrade {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  background: white;
  color: #4f46e5;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-base);
  width: 100%;
  text-align: center;
}

.btn-inline-upgrade:hover {
  background: #f8fafc;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  color: #4f46e5;
}

/* Accent Link */
.link-accent {
  color: #4f46e5;
  font-weight: 600;
  margin-left: 8px;
  text-decoration: none;
  transition: color var(--transition-fast);
}

.link-accent:hover {
  color: #4338ca;
  text-decoration: underline;
}

/* Small Accent Link */
.link-accent-sm {
  color: #4f46e5;
  font-size: 12px;
  text-decoration: none;
  transition: color var(--transition-fast);
}

.link-accent-sm:hover {
  color: #4338ca;
  text-decoration: underline;
}

/* Share Action Buttons (white buttons on colored bg) */
.btn-share-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 16px;
  background: white;
  color: var(--primary);
  border: none;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  flex-shrink: 0;
  transition: all var(--transition-base);
}

.btn-share-action:hover {
  background: #f8fafc;
  transform: translateY(-1px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

/* Focus states for inline buttons (accessibility) */
.btn-inline-primary:focus-visible,
.btn-inline-secondary:focus-visible,
.btn-inline-warning:focus-visible,
.btn-inline-upgrade:focus-visible,
.btn-share-action:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ================================== */
/* CARD SYSTEM */
/* ================================== */

.card {
  background: var(--bg-primary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card--interactive {
  cursor: pointer;
}

.card--interactive:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.card__header {
  margin-bottom: var(--space-4);
}

.card__title {
  font-size: var(--text-xl);
  font-weight: var(--weight-semibold);
  color: var(--text-primary);
  margin: 0 0 var(--space-2) 0;
}

.card__subtitle {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  margin: 0;
}

.card__body {
  color: var(--text-secondary);
  line-height: var(--line-normal);
}

.card__footer {
  margin-top: var(--space-6);
  padding-top: var(--space-4);
  border-top: 1px solid var(--border-light);
}

/* ================================== */
/* FORM SYSTEM */
/* ================================== */

.form-group {
  margin-bottom: var(--space-5);
}

.form-label {
  display: block;
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  font-family: var(--font-sans);
  font-size: var(--text-base);
  color: var(--text-primary);
  background: var(--white);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  outline: none;
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-input::placeholder,
.form-textarea::placeholder {
  color: var(--text-muted);
}

.form-input:disabled,
.form-textarea:disabled,
.form-select:disabled {
  background: var(--gray-50);
  color: var(--text-disabled);
  cursor: not-allowed;
}

.form-textarea {
  min-height: 120px;
  resize: vertical;
}

.form-help {
  display: block;
  margin-top: var(--space-2);
  font-size: var(--text-sm);
  color: var(--text-muted);
}

.form-error {
  display: block;
  margin-top: var(--space-2);
  font-size: var(--text-sm);
  color: var(--error);
}

/* ================================== */
/* ALERT SYSTEM */
/* ================================== */

.alert {
  padding: var(--space-4) var(--space-5);
  border-radius: var(--radius-md);
  border-left: 4px solid;
  font-size: var(--text-sm);
  line-height: var(--line-normal);
  margin-bottom: var(--space-4);
}

.alert--info {
  background: #e0f2fe;
  border-color: var(--info);
  color: #075985;
}

.alert--success {
  background: #d1fae5;
  border-color: var(--success);
  color: #065f46;
}

.alert--warning {
  background: #fef3c7;
  border-color: var(--warning);
  color: #92400e;
}

.alert--error {
  background: #fee2e2;
  border-color: var(--error);
  color: #991b1b;
}

/* ================================== */
/* BADGE SYSTEM */
/* ================================== */

.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--space-1) var(--space-3);
  font-size: var(--text-xs);
  font-weight: var(--weight-medium);
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.025em;
}

.badge--primary {
  background: var(--gray-100);
  color: var(--gray-700);
}

.badge--success {
  background: #d1fae5;
  color: #065f46;
}

.badge--warning {
  background: #fef3c7;
  color: #92400e;
}

.badge--error {
  background: #fee2e2;
  color: #991b1b;
}

.badge--info {
  background: #e0f2fe;
  color: #075985;
}

/* ================================== */
/* UTILITY CLASSES */
/* ================================== */

/* Spacing */
.mt-0 { margin-top: 0; }
.mt-2 { margin-top: var(--space-2); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }

.mb-0 { margin-bottom: 0; }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }

.mx-auto { margin-left: auto; margin-right: auto; }

/* Text */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-primary { color: var(--text-primary); }
.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }
.text-white { color: var(--white); }

.text-sm { font-size: var(--text-sm); }
.text-base { font-size: var(--text-base); }
.text-lg { font-size: var(--text-lg); }
.text-xl { font-size: var(--text-xl); }
.text-2xl { font-size: var(--text-2xl); }
.text-3xl { font-size: var(--text-3xl); }

.font-medium { font-weight: var(--weight-medium); }
.font-semibold { font-weight: var(--weight-semibold); }
.font-bold { font-weight: var(--weight-bold); }

/* Display */
.flex { display: flex; }
.inline-flex { display: inline-flex; }
.grid { display: grid; }
.block { display: block; }
.inline-block { display: inline-block; }
.hidden { display: none; }

/* Flexbox */
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.items-end { align-items: flex-end; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: var(--space-2); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }

/* Width */
.w-full { width: 100%; }
.max-w-sm { max-width: 24rem; }
.max-w-md { max-width: 28rem; }
.max-w-lg { max-width: 32rem; }
.max-w-xl { max-width: 36rem; }
.max-w-2xl { max-width: 42rem; }
.max-w-4xl { max-width: 56rem; }
.max-w-6xl { max-width: 72rem; }

/* Borders */
.border { border: 1px solid var(--border-light); }
.border-t { border-top: 1px solid var(--border-light); }
.border-b { border-bottom: 1px solid var(--border-light); }
.rounded { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-full { border-radius: var(--radius-full); }

/* Shadows */
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }

/* Opacity */
.opacity-50 { opacity: 0.5; }
.opacity-75 { opacity: 0.75; }

/* Cursor */
.cursor-pointer { cursor: pointer; }
.cursor-not-allowed { cursor: not-allowed; }