/**
 * 禪閱 ZenRead — Design System
 * Shared CSS tokens, typography, and utility classes
 */

/* ─── Google Fonts ─── */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Noto+Serif+TC:wght@300;400;500;700&display=swap');
@import url('https://fonts.googleapis.com/css2?family=Material+Symbols+Outlined:opsz,wght,FILL,GRAD@20..48,100..700,0..1,-50..200&display=swap');

/* ─── Design Tokens ─── */
:root {
  /* Colors */
  --color-primary:         #7B8C7C;
  --color-primary-light:   #96a697;
  --color-primary-ultra:   rgba(123,140,124,0.08);
  --color-bg:              #F9F8F6;
  --color-surface:         #FFFFFF;
  --color-surface-2:       #F4F2EF;
  --color-text:            #2C2B29;
  --color-text-muted:      #9CA3AF;
  --color-text-soft:       #6B7280;
  --color-border:          #D4CFC7;
  --color-border-light:    rgba(212,207,199,0.4);

  /* Dark mode colors */
  --color-dark-bg:         #112120;
  --color-dark-surface:    #1a2e2d;
  --color-dark-surface-2:  #223433;
  --color-dark-text:       #E8E4DF;
  --color-dark-text-muted: #6B7280;
  --color-dark-border:     rgba(212,207,199,0.15);

  /* Typography */
  --font-ui:               'Inter', 'Noto Sans TC', system-ui, sans-serif;
  --font-content:          'Noto Serif TC', 'Georgia', 'PMingLiU', serif;
  --font-mono:             ui-monospace, 'SFMono-Regular', 'Menlo', 'Monaco', 'Consolas', monospace;

  /* Spacing scale */
  --space-xs:  4px;
  --space-sm:  8px;
  --space-md:  16px;
  --space-lg:  24px;
  --space-xl:  32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  --space-4xl: 96px;

  /* Border radius */
  --radius-sm:   2px;
  --radius-md:   4px;
  --radius-lg:   8px;
  --radius-xl:   12px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm:   0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md:   0 4px 12px rgba(0,0,0,0.06), 0 2px 4px rgba(0,0,0,0.04);
  --shadow-lg:   0 8px 24px rgba(0,0,0,0.09), 0 3px 6px rgba(0,0,0,0.05);

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

  /* Z-index scale */
  --z-below:   -1;
  --z-base:     0;
  --z-sticky:  10;
  --z-nav:     40;
  --z-modal:   80;
  --z-overlay: 90;
  --z-toast:   100;
}

/* Dark mode token overrides */
.dark {
  --color-bg:             var(--color-dark-bg);
  --color-surface:        var(--color-dark-surface);
  --color-surface-2:      var(--color-dark-surface-2);
  --color-text:           var(--color-dark-text);
  --color-text-muted:     var(--color-dark-text-muted);
  --color-border:         var(--color-dark-border);
  --color-border-light:   rgba(212,207,199,0.1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-ui);
  background-color: var(--color-bg);
  color: var(--color-text);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color var(--transition-slow), color var(--transition-slow);
}

a {
  color: inherit;
  text-decoration: none;
}

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

/* ─── Material Symbols ─── */
.material-symbols-outlined {
  font-family: 'Material Symbols Outlined';
  font-weight: normal;
  font-style: normal;
  font-size: 24px;
  line-height: 1;
  letter-spacing: normal;
  text-transform: none;
  display: inline-block;
  white-space: nowrap;
  word-wrap: normal;
  direction: ltr;
  -webkit-font-feature-settings: 'liga';
  font-feature-settings: 'liga';
  -webkit-font-smoothing: antialiased;
  font-variation-settings: 'FILL' 0, 'wght' 400, 'GRAD' 0, 'opsz' 24;
  vertical-align: middle;
  user-select: none;
}

.icon-fill { font-variation-settings: 'FILL' 1, 'wght' 400, 'GRAD' 0, 'opsz' 24; }
.icon-sm   { font-size: 18px; }
.icon-lg   { font-size: 32px; }

/* ─── Typography utilities ─── */
.font-ui      { font-family: var(--font-ui); }
.font-content { font-family: var(--font-content); }
.font-mono    { font-family: var(--font-mono); }

/* ─── Zen scrollbar ─── */
::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background-color: var(--color-border); border-radius: var(--radius-full); }
::-webkit-scrollbar-thumb:hover { background-color: var(--color-primary); }

/* ─── Selection ─── */
::selection { background-color: rgba(123,140,124,0.2); color: var(--color-text); }

/* ─── Animation keyframes ─── */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0.4; }
}

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

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

@keyframes blink {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0; }
}

@keyframes shimmer {
  0%   { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

.animate-fade-in     { animation: fadeIn 0.4s ease both; }
.animate-fade-in-up  { animation: fadeInUp 0.5s ease both; }
.animate-pulse       { animation: pulse 2s cubic-bezier(0.4,0,0.6,1) infinite; }
.animate-spin        { animation: spin 1s linear infinite; }
.animate-blink       { animation: blink 1s step-end infinite; }

/* ─── Stagger delays ─── */
.delay-100 { animation-delay: 100ms; }
.delay-200 { animation-delay: 200ms; }
.delay-300 { animation-delay: 300ms; }
.delay-400 { animation-delay: 400ms; }
.delay-500 { animation-delay: 500ms; }

/* ─── Vertical text utility ─── */
.vertical-text {
  writing-mode: vertical-rl;
  text-orientation: mixed;
}

/* ─── Toggle Switch ─── */
.toggle-wrapper { display: inline-flex; align-items: center; cursor: pointer; }

.toggle-input { position: absolute; opacity: 0; width: 0; height: 0; }

.toggle-track {
  position: relative;
  width: 44px;
  height: 24px;
  background-color: var(--color-border);
  border-radius: var(--radius-full);
  transition: background-color var(--transition-fast);
  flex-shrink: 0;
}

.toggle-track::after {
  content: '';
  position: absolute;
  top: 2px;
  left: 2px;
  width: 20px;
  height: 20px;
  background-color: white;
  border-radius: 50%;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast);
}

.toggle-input:checked + .toggle-track {
  background-color: var(--color-primary);
}

.toggle-input:checked + .toggle-track::after {
  transform: translateX(20px);
}

/* ─── Button base ─── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-family: var(--font-ui);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
}

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

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

.btn-outline {
  background-color: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}

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

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

.btn-ghost:hover {
  background-color: var(--color-surface-2);
  color: var(--color-text);
}

/* ─── Card base ─── */
.card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-normal);
}

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

/* ─── Status badge ─── */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.badge-primary   { background-color: var(--color-primary-ultra); color: var(--color-primary); }
.badge-success   { background-color: rgba(34,197,94,0.1); color: #16a34a; }
.badge-warning   { background-color: rgba(250,204,21,0.15); color: #b45309; }
.badge-danger    { background-color: rgba(239,68,68,0.1); color: #dc2626; }
.badge-muted     { background-color: var(--color-surface-2); color: var(--color-text-muted); }

/* ─── Loading shimmer ─── */
.skeleton {
  background: linear-gradient(90deg, var(--color-surface-2) 25%, var(--color-border-light) 50%, var(--color-surface-2) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: var(--radius-md);
}

/* ─── Page transition ─── */
.page-enter {
  animation: fadeInUp 0.4s ease both;
}