/**
 * SKOOLYST Public Website – Design System
 * Single source of truth for colors, typography, spacing, buttons, cards, inputs.
 */

:root {
  /* ========== Colors ========== */
  --color-primary: #0f4077;
  --color-primary-hover: #0a2d52;
  --color-primary-light: rgba(15, 64, 119, 0.08);
  
  --color-secondary: #4361ee;
  --color-secondary-hover: #3651d4;
  --color-secondary-light: rgba(67, 97, 238, 0.1);
  
  --color-neutral-bg: #f8fafb;
  --color-neutral-bg-alt: #f1f5f9;
  --color-neutral-border: #e2e8f0;
  --color-neutral-border-light: #f1f5f9;
  --color-neutral-text: #1e293b;
  --color-neutral-muted: #64748b;
  --color-neutral-muted-light: #94a3b8;
  
  --color-white: #ffffff;
  --color-success: #0d9488;
  --color-warning: #d97706;
  --color-danger: #dc2626;
  
  /* ========== Typography ========== */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-size-xs: 0.75rem;    /* 12px */
  --font-size-sm: 0.875rem;   /* 14px */
  --font-size-base: 1rem;     /* 16px */
  --font-size-lg: 1.125rem;   /* 18px */
  --font-size-xl: 1.25rem;    /* 20px */
  --font-size-2xl: 1.5rem;    /* 24px */
  --font-size-3xl: 2rem;      /* 32px */
  --font-size-4xl: 2.5rem;    /* 40px */
  
  --font-weight-normal: 400;
  --font-weight-medium: 600;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --font-weight-extrabold: 800;
  
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.625;
  
  /* ========== Spacing (8px 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: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;
  
  /* ========== Shadows ========== */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.06);
  --shadow-card: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-card-hover: 0 8px 24px rgba(0, 0, 0, 0.1);
  
  /* ========== Transitions ========== */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-smooth: 250ms ease;
}

/* ========== Typography classes ========== */
.site-h1 {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-neutral-text);
}
.site-h2 {
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-neutral-text);
}
.site-h3 {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-normal);
  color: var(--color-neutral-text);
}
.site-h4 {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-normal);
  color: var(--color-neutral-text);
}
.site-body {
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  line-height: var(--line-height-relaxed);
  color: var(--color-neutral-text);
}
.site-muted {
  color: var(--color-neutral-muted);
  font-size: var(--font-size-sm);
}

/* ========== Buttons – base ========== */
.btn-site {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-5);
  font-family: var(--font-family);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  line-height: 1.25;
  border-radius: var(--radius-md);
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background-color var(--transition-base), border-color var(--transition-base), color var(--transition-base), box-shadow var(--transition-base), transform var(--transition-base);
  white-space: nowrap;
}
.btn-site:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px var(--color-secondary-light);
}
.btn-site:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

/* Primary */
.btn-site-primary {
  background: var(--color-primary);
  color: var(--color-white);
  border-color: var(--color-primary);
}
.btn-site-primary:hover:not(:disabled) {
  background: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
  color: var(--color-white);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}
.btn-site-primary:focus-visible {
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

/* Secondary */
.btn-site-secondary {
  background: var(--color-secondary);
  color: var(--color-white);
  border-color: var(--color-secondary);
}
.btn-site-secondary:hover:not(:disabled) {
  background: var(--color-secondary-hover);
  border-color: var(--color-secondary-hover);
  color: var(--color-white);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* Outline */
.btn-site-outline {
  background: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}
.btn-site-outline:hover:not(:disabled) {
  background: var(--color-primary-light);
  color: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
  transform: translateY(-1px);
}

/* Outline secondary (e.g. login) */
.btn-site-outline-secondary {
  background: transparent;
  color: var(--color-secondary);
  border-color: var(--color-secondary);
}
.btn-site-outline-secondary:hover:not(:disabled) {
  background: var(--color-secondary-light);
  color: var(--color-secondary-hover);
  border-color: var(--color-secondary-hover);
  transform: translateY(-1px);
}

/* ========== Cards ========== */
.card-site {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  box-shadow: var(--shadow-card);
  border: 1px solid var(--color-neutral-border-light);
  transition: box-shadow var(--transition-smooth), transform var(--transition-smooth), border-color var(--transition-smooth);
}
.card-site:hover {
  box-shadow: var(--shadow-card-hover);
  border-color: var(--color-neutral-border);
}

/* ========== Inputs & Search ========== */
.input-site,
.select-site {
  display: block;
  width: 100%;
  height: 44px;
  padding: 0 var(--space-4);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-neutral-text);
  background: var(--color-white);
  border: 1px solid var(--color-neutral-border);
  border-radius: var(--radius-md);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}
.input-site::placeholder {
  color: var(--color-neutral-muted-light);
}
.input-site:focus,
.select-site:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}
.select-site {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2364748b' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--space-4) center;
  padding-right: 2.5rem;
}

/* Search bar block (below header) */
.search-bar-site {
  display: flex;
  align-items: stretch;
  max-width: 640px;
  margin: 0 auto;
  background: var(--color-white);
  border: 1px solid var(--color-neutral-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-md);
  overflow: hidden;
}
.search-bar-site .search-bar-input {
  flex: 1;
  height: 48px;
  padding: 0 var(--space-4);
  font-size: var(--font-size-base);
  border: none;
  border-radius: 0;
}
.search-bar-site .search-bar-input:focus {
  outline: none;
  box-shadow: inset 0 0 0 2px var(--color-primary);
}
.search-bar-site .search-bar-btn {
  flex-shrink: 0;
  padding: 0 var(--space-5);
  height: 48px;
  background: var(--color-primary);
  color: var(--color-white);
  border: none;
  font-weight: var(--font-weight-semibold);
  font-size: var(--font-size-sm);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}
.search-bar-site .search-bar-btn:hover {
  background: var(--color-primary-hover);
}

/* ========== Section spacing ========== */
.section-site {
  padding-top: var(--space-16);
  padding-bottom: var(--space-16);
}
.section-site-alt {
  background: var(--color-neutral-bg);
}

/* ========== Page header (banner under nav) ========== */
.page-header-site {
  background: var(--color-primary);
  color: var(--color-white);
  padding: var(--space-8) 0;
  text-align: center;
}
.page-header-site .page-title-site {
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-bold);
  margin-bottom: var(--space-2);
  color: var(--color-white);
}
.page-header-site .page-subtitle-site {
  font-size: var(--font-size-base);
  opacity: 0.95;
  color: var(--color-white);
  margin: 0;
}

/* ========== Filter strip ========== */
.filter-strip-site {
  background: var(--color-neutral-bg);
  padding: var(--space-6) 0;
  border-bottom: 1px solid var(--color-neutral-border);
}
.filter-strip-site .filter-label-site {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-neutral-muted);
  margin-bottom: var(--space-2);
}
.filter-strip-site .filter-select,
.filter-strip-site .input-site {
  height: 44px;
}

/* ========== Badge / tag ========== */
.badge-site {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-full);
  background: var(--color-primary);
  color: var(--color-white);
}
.tag-site {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  font-size: var(--font-size-xs);
  color: var(--color-neutral-muted);
  background: var(--color-neutral-bg);
  border: 1px solid var(--color-neutral-border);
  border-radius: var(--radius-full);
}