/* =============================================================================
   Caya Music — Main CSS Design System
   Requirements: 19.1, 19.5, 19.6, 19.7
   ============================================================================= */

/* ---------------------------------------------------------------------------
   1. CSS Custom Properties (Design Tokens)
   --------------------------------------------------------------------------- */
:root {
  /* Colors */
  --color-base:        #ffffff;
  --color-accent:      #1a1a2e;
  --color-accent-mid:  #16213e;
  --color-highlight:   #e94560;
  --color-text:        #1a1a2e;
  --color-text-muted:  #666666;
  --color-text-light:  #999999;
  --color-border:      #e0e0e0;
  --color-bg-light:    #f5f5f5;
  --color-bg-dark:     #0f0f1a;
  --color-success:     #28a745;
  --color-error:       #dc3545;
  --color-warning:     #ffc107;

  /* Typography */
  --font-sans:   'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-size-xs:   0.75rem;   /* 12px */
  --font-size-sm:   0.875rem;  /* 14px */
  --font-size-base: 1rem;      /* 16px */
  --font-size-md:   1.125rem;  /* 18px */
  --font-size-lg:   1.25rem;   /* 20px */
  --font-size-xl:   1.5rem;    /* 24px */
  --font-size-2xl:  2rem;      /* 32px */
  --font-size-3xl:  2.5rem;    /* 40px */
  --font-size-4xl:  3rem;      /* 48px */
  --line-height-tight:  1.25;
  --line-height-normal: 1.6;
  --line-height-loose:  1.8;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Border radius */
  --radius-sm:   4px;
  --radius-md:   8px;
  --radius-lg:   12px;
  --radius-xl:   16px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm:  0 1px 3px rgba(0,0,0,.08);
  --shadow-md:  0 4px 12px rgba(0,0,0,.12);
  --shadow-lg:  0 8px 24px rgba(0,0,0,.16);
  --shadow-xl:  0 16px 48px rgba(0,0,0,.20);

  /* Transitions */
  --transition-fast:   150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow:   400ms ease;

  /* Layout */
  --container-max: 1200px;
  --container-pad: var(--space-6);
  --header-height: 56px;  /* synced with header.css */
}

/* ---------------------------------------------------------------------------
   2. CSS Reset / Normalize
   --------------------------------------------------------------------------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background-color: var(--color-base);
  -webkit-font-smoothing: antialiased;
}

img, video, svg {
  display: block;
  max-width: 100%;
}

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

ul, ol { list-style: none; }

button, input, select, textarea {
  font: inherit;
  border: none;
  background: none;
}

button { cursor: pointer; }

/* ---------------------------------------------------------------------------
   3. Base Typography
   --------------------------------------------------------------------------- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: var(--line-height-tight);
  color: var(--color-text);
}
h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }
h6 { font-size: var(--font-size-md); }

p { margin-bottom: var(--space-4); }
p:last-child { margin-bottom: 0; }

strong { font-weight: 700; }
em     { font-style: italic; }

/* ---------------------------------------------------------------------------
   4. Layout Utilities
   --------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

.grid {
  display: grid;
  gap: var(--space-6);
}
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.flex        { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.flex-between{ display: flex; align-items: center; justify-content: space-between; }
.flex-wrap   { flex-wrap: wrap; }
.gap-2  { gap: var(--space-2); }
.gap-4  { gap: var(--space-4); }
.gap-6  { gap: var(--space-6); }
.gap-8  { gap: var(--space-8); }

.text-center { text-align: center; }
.text-right  { text-align: right; }
.text-muted  { color: var(--color-text-muted); }
.text-sm     { font-size: var(--font-size-sm); }
.text-lg     { font-size: var(--font-size-lg); }

.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

.hidden { display: none !important; }

/* ---------------------------------------------------------------------------
   5. Button Components
   --------------------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-base);
  font-weight: 600;
  line-height: 1;
  text-decoration: none;
  transition: background var(--transition-fast), color var(--transition-fast),
              border-color var(--transition-fast), opacity var(--transition-fast);
  cursor: pointer;
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-accent);
  color: var(--color-base);
  border: 2px solid var(--color-accent);
}
.btn-primary:hover {
  background: var(--color-accent-mid);
  border-color: var(--color-accent-mid);
  color: var(--color-base);
}

.btn-secondary {
  background: var(--color-highlight);
  color: var(--color-base);
  border: 2px solid var(--color-highlight);
}
.btn-secondary:hover {
  opacity: 0.88;
  color: var(--color-base);
}

.btn-outline {
  background: transparent;
  color: var(--color-accent);
  border: 2px solid var(--color-accent);
}
.btn-outline:hover {
  background: var(--color-accent);
  color: var(--color-base);
}

.btn-outline-light {
  background: transparent;
  color: var(--color-base);
  border: 2px solid var(--color-base);
}
.btn-outline-light:hover {
  background: var(--color-base);
  color: var(--color-accent);
}

.btn:disabled,
.btn[disabled] {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

.btn-sm { padding: var(--space-2) var(--space-4); font-size: var(--font-size-sm); }
.btn-lg { padding: var(--space-4) var(--space-8); font-size: var(--font-size-lg); }

/* ---------------------------------------------------------------------------
   6. Form Inputs
   --------------------------------------------------------------------------- */
.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-bottom: var(--space-5);
}

.form-label {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-text);
}

.form-control {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-base);
  color: var(--color-text);
  background: var(--color-base);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}
.form-control:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(26,26,46,.12);
}
.form-control.is-invalid {
  border-color: var(--color-error);
}
.form-control.is-invalid:focus {
  box-shadow: 0 0 0 3px rgba(220,53,69,.15);
}

select.form-control { appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%23666' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right var(--space-4) center; padding-right: var(--space-10); }

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

.form-error {
  font-size: var(--font-size-sm);
  color: var(--color-error);
}

/* ---------------------------------------------------------------------------
   7. Card Component
   --------------------------------------------------------------------------- */
.card {
  background: var(--color-base);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: box-shadow var(--transition-normal), transform var(--transition-normal);
}
.card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.card-img {
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
}

.card-body {
  padding: var(--space-5);
}

.card-title {
  font-size: var(--font-size-lg);
  font-weight: 700;
  margin-bottom: var(--space-2);
}

.card-text {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: var(--line-height-normal);
}

/* ---------------------------------------------------------------------------
   8. Badge Styles
   --------------------------------------------------------------------------- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.badge-sold-out {
  background: var(--color-error);
  color: var(--color-base);
}

.badge-new {
  background: var(--color-success);
  color: var(--color-base);
}

.badge-type {
  background: var(--color-accent);
  color: var(--color-base);
}

/* ---------------------------------------------------------------------------
   9. Pagination
   --------------------------------------------------------------------------- */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  margin-top: var(--space-10);
}

.pagination a,
.pagination span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  font-size: var(--font-size-sm);
  font-weight: 600;
  border: 1.5px solid var(--color-border);
  color: var(--color-text);
  transition: background var(--transition-fast), color var(--transition-fast);
}

.pagination a:hover {
  background: var(--color-accent);
  color: var(--color-base);
  border-color: var(--color-accent);
}

.pagination .active {
  background: var(--color-accent);
  color: var(--color-base);
  border-color: var(--color-accent);
}

.pagination .disabled {
  opacity: 0.4;
  pointer-events: none;
}

/* ---------------------------------------------------------------------------
   10. Flash Messages
   --------------------------------------------------------------------------- */
.flash {
  padding: var(--space-4) var(--space-5);
  border-radius: var(--radius-sm);
  margin-bottom: var(--space-5);
  font-size: var(--font-size-sm);
  font-weight: 500;
}

.flash-success {
  background: #d4edda;
  color: #155724;
  border: 1px solid #c3e6cb;
}

.flash-error {
  background: #f8d7da;
  color: #721c24;
  border: 1px solid #f5c6cb;
}

.flash-warning {
  background: #fff3cd;
  color: #856404;
  border: 1px solid #ffeeba;
}

.flash-info {
  background: #d1ecf1;
  color: #0c5460;
  border: 1px solid #bee5eb;
}

/* ---------------------------------------------------------------------------
   11. Modal Overlay
   --------------------------------------------------------------------------- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.75);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: var(--space-6);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-normal), visibility var(--transition-normal);
}

.modal-overlay.is-open {
  opacity: 1;
  visibility: visible;
}

.modal {
  background: var(--color-base);
  border-radius: var(--radius-lg);
  max-width: 640px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  position: relative;
  box-shadow: var(--shadow-xl);
}

.modal-close {
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  background: var(--color-bg-light);
  color: var(--color-text-muted);
  font-size: var(--font-size-lg);
  cursor: pointer;
  transition: background var(--transition-fast);
}
.modal-close:hover { background: var(--color-border); }

/* ---------------------------------------------------------------------------
   12. Loading Spinner
   --------------------------------------------------------------------------- */
.spinner {
  display: inline-block;
  width: 24px;
  height: 24px;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

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

/* ---------------------------------------------------------------------------
   13. Section Utilities
   --------------------------------------------------------------------------- */
.section {
  padding-block: var(--space-20);
}

.section-sm {
  padding-block: var(--space-12);
}

.section-title {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-bottom: var(--space-4);
}

.section-subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-text-muted);
  margin-bottom: var(--space-10);
}

/* ---------------------------------------------------------------------------
   14. Responsive Breakpoints
   --------------------------------------------------------------------------- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  :root {
    --font-size-4xl: 2.25rem;
    --font-size-3xl: 1.875rem;
    --container-pad: var(--space-4);
  }

  .grid-4,
  .grid-3,
  .grid-2 { grid-template-columns: 1fr; }

  .section { padding-block: var(--space-12); }
}

@media (max-width: 480px) {
  :root {
    --font-size-4xl: 1.875rem;
    --font-size-3xl: 1.5rem;
  }
}