/* ==========================================================================
   Base — Reset, Typography, Layout Primitives
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400&display=swap');

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

html {
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-secondary);
  min-height: 100vh;
  transition: background-color var(--transition-slow), color var(--transition-slow);
}

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

a {
  color: var(--accent-blue);
  text-decoration: none;
  transition: color var(--transition);
}

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

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

button {
  cursor: pointer;
}

ul,
ol {
  list-style: none;
}

table {
  border-collapse: collapse;
  border-spacing: 0;
}

/* ---- Selection ---- */
::selection {
  background-color: var(--accent-blue);
  color: #FFFFFF;
}

/* ---- Scrollbar (Webkit) ---- */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--text-tertiary);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-secondary);
}

/* ---- Typography ---- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.25;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

h1 {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.025em;
}

h2 {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

h3 {
  font-size: 22px;
}

h4 {
  font-size: 18px;
}

h5 {
  font-size: 16px;
}

h6 {
  font-size: 14px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-secondary);
}

p {
  color: var(--text-secondary);
  line-height: 1.65;
}

small {
  font-size: 13px;
  color: var(--text-secondary);
}

.mono {
  font-family: var(--font-mono);
  font-size: 0.92em;
  letter-spacing: -0.02em;
}

/* ---- Layout Primitives ---- */
.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.page-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-md);
  padding-bottom: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  border-bottom: 1px solid var(--border-color);
}

.page-header h1,
.page-header h2 {
  margin: 0;
}

.page-header .page-header-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.page-content {
  /* Padding provided by .main-content; no extra padding needed here */
}

/* ---- Theme Transition ---- */
body.theme-transitioning,
body.theme-transitioning *,
body.theme-transitioning *::before,
body.theme-transitioning *::after {
  transition-property: background-color, border-color, box-shadow, color;
  transition-duration: 0.35s !important;
  transition-timing-function: ease;
}

/* ---- Utility ---- */
.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;
}

.text-truncate {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}