/* ============================================================
   Atlas Design System — main.css
   Custom properties, reset, base typography, layout
   ============================================================ */

/* ── Custom Properties: Dark Theme (default) ─────────────────── */
:root,
[data-theme="dark"] {
  /* Backgrounds */
  --bg-page:      #09090f;
  --bg-elevated:  #111118;
  --bg-card:      #111118;
  --bg-input:     #1a1a26;
  --bg-hover:     #1e1e2e;
  --bg-active:    #252538;

  /* Glass */
  --glass-bg:     rgba(255,255,255,0.04);
  --glass-hover:  rgba(255,255,255,0.07);
  --glass-active: rgba(255,255,255,0.10);
  --glass-border: rgba(255,255,255,0.08);
  --glass-strong: rgba(255,255,255,0.14);

  /* Text */
  --text-1:       #f0f0f6;
  --text-2:       rgba(240,240,246,0.65);
  --text-3:       rgba(240,240,246,0.38);
  --text-inverse: #09090f;

  /* Accent (Indigo) */
  --accent:       #6366f1;
  --accent-hover: #818cf8;
  --accent-dim:   rgba(99,102,241,0.15);
  --accent-glow:  rgba(99,102,241,0.28);

  /* Status colours */
  --success:      #22c55e;
  --success-dim:  rgba(34,197,94,0.12);
  --warning:      #f59e0b;
  --warning-dim:  rgba(245,158,11,0.12);
  --danger:       #ef4444;
  --danger-dim:   rgba(239,68,68,0.12);
  --info:         #3b82f6;
  --info-dim:     rgba(59,130,246,0.12);

  /* Category accent colours */
  --cat-linux:    #f97316;
  --cat-docker:   #2563eb;
  --cat-proxmox:  #7c3aed;
  --cat-network:  #0891b2;
  --cat-ha:       #16a34a;
  --cat-nas:      #9333ea;
  --cat-homelab:  #db2777;
  --cat-tutorial: #0d9488;
  --cat-news:     #dc2626;
  --cat-compare:  #ca8a04;

  /* Borders */
  --border:       rgba(255,255,255,0.08);
  --border-strong:rgba(255,255,255,0.16);

  /* Shadows */
  --shadow-xs: 0 1px 2px rgba(0,0,0,.5);
  --shadow-sm: 0 2px 8px rgba(0,0,0,.5);
  --shadow-md: 0 4px 20px rgba(0,0,0,.55);
  --shadow-lg: 0 8px 40px rgba(0,0,0,.6);
  --shadow-glow: 0 0 28px rgba(99,102,241,.25);

  /* Scrollbar */
  --scrollbar-track: #111118;
  --scrollbar-thumb: #2a2a3e;
  --scrollbar-hover: #3a3a52;

  color-scheme: dark;
}

[data-theme="light"] {
  --bg-page:      #f5f5fa;
  --bg-elevated:  #ffffff;
  --bg-card:      #ffffff;
  --bg-input:     #f0f0f8;
  --bg-hover:     #ebebf5;
  --bg-active:    #e2e2ef;

  --glass-bg:     rgba(255,255,255,0.72);
  --glass-hover:  rgba(255,255,255,0.88);
  --glass-active: rgba(255,255,255,0.96);
  --glass-border: rgba(0,0,0,0.07);
  --glass-strong: rgba(0,0,0,0.12);

  --text-1:       #111118;
  --text-2:       rgba(17,17,24,0.60);
  --text-3:       rgba(17,17,24,0.38);
  --text-inverse: #f0f0f6;

  --accent:       #4f46e5;
  --accent-hover: #6366f1;
  --accent-dim:   rgba(79,70,229,0.10);
  --accent-glow:  rgba(79,70,229,0.20);

  --border:        rgba(0,0,0,0.08);
  --border-strong: rgba(0,0,0,0.16);

  --shadow-xs: 0 1px 2px rgba(0,0,0,.06);
  --shadow-sm: 0 2px 8px rgba(0,0,0,.08);
  --shadow-md: 0 4px 20px rgba(0,0,0,.10);
  --shadow-lg: 0 8px 40px rgba(0,0,0,.12);
  --shadow-glow: 0 0 28px rgba(79,70,229,0.18);

  --scrollbar-track: #f0f0f8;
  --scrollbar-thumb: #c8c8dc;
  --scrollbar-hover: #adadc9;

  color-scheme: light;
}

/* ── Shared spacing / radius / type tokens ───────────────────── */
:root {
  /* Spacing scale (4px base) */
  --sp-1:  0.25rem;  /* 4px  */
  --sp-2:  0.5rem;   /* 8px  */
  --sp-3:  0.75rem;  /* 12px */
  --sp-4:  1rem;     /* 16px */
  --sp-5:  1.25rem;  /* 20px */
  --sp-6:  1.5rem;   /* 24px */
  --sp-8:  2rem;     /* 32px */
  --sp-10: 2.5rem;   /* 40px */
  --sp-12: 3rem;     /* 48px */
  --sp-16: 4rem;     /* 64px */
  --sp-20: 5rem;     /* 80px */
  --sp-24: 6rem;     /* 96px */

  /* Border radius */
  --r-xs:   3px;
  --r-sm:   6px;
  --r-md:   10px;
  --r-lg:   14px;
  --r-xl:   20px;
  --r-2xl:  28px;
  --r-full: 9999px;

  /* Typography */
  --font-sans:    -apple-system, BlinkMacSystemFont, 'SF Pro Text', 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-display: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', sans-serif;
  --font-mono:    'JetBrains Mono', 'Fira Code', 'SF Mono', 'Cascadia Code', Consolas, 'Courier New', monospace;

  /* Type scale */
  --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 */
  --text-5xl:  3rem;      /* 48px */
  --text-6xl:  3.75rem;   /* 60px */

  /* Line heights */
  --leading-tight: 1.2;
  --leading-snug:  1.35;
  --leading-base:  1.6;
  --leading-loose: 1.8;

  /* Transitions */
  --ease-out:  cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in:   cubic-bezier(0.7, 0, 0.84, 0);
  --t-fast:    120ms var(--ease-out);
  --t-base:    200ms var(--ease-out);
  --t-slow:    400ms var(--ease-out);

  /* Layout */
  --nav-h:       64px;
  --sidebar-w:   260px;
  --content-max: 1280px;
  --article-max: 760px;
  --prose-max:   680px;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  tab-size: 2;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-base);
  color: var(--text-1);
  background-color: var(--bg-page);
  min-height: 100dvh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

input, button, textarea, select {
  font: inherit;
}

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

ul, ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: var(--leading-tight);
  letter-spacing: -0.02em;
  color: var(--text-1);
}

p {
  color: var(--text-2);
}

button {
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}

/* ── Custom Scrollbar ────────────────────────────────────────── */
::-webkit-scrollbar               { width: 8px; height: 8px; }
::-webkit-scrollbar-track         { background: var(--scrollbar-track); }
::-webkit-scrollbar-thumb         { background: var(--scrollbar-thumb); border-radius: var(--r-full); }
::-webkit-scrollbar-thumb:hover   { background: var(--scrollbar-hover); }

/* ── Selection ───────────────────────────────────────────────── */
::selection {
  background: var(--accent-glow);
  color: var(--text-1);
}

/* ── Focus ring ──────────────────────────────────────────────── */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: var(--r-sm);
}

/* ── Layout ──────────────────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--content-max);
  margin-inline: auto;
  padding-inline: var(--sp-6);
}

@media (min-width: 1024px) {
  .container { padding-inline: var(--sp-8); }
}

.section {
  padding-block: var(--sp-16);
}

.section-sm {
  padding-block: var(--sp-10);
}

/* ── Grid ────────────────────────────────────────────────────── */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(1, 1fr);
  gap: var(--sp-6);
}
.grid-3 {
  display: grid;
  grid-template-columns: repeat(1, 1fr);
  gap: var(--sp-6);
}
.grid-4 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--sp-4);
}

@media (min-width: 640px) {
  .grid-2 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 768px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 1024px) {
  .grid-3 { grid-template-columns: repeat(3, 1fr); }
  .grid-4 { grid-template-columns: repeat(4, 1fr); }
}

/* ── Flex utilities ──────────────────────────────────────────── */
.flex       { display: flex; }
.flex-col   { display: flex; flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.justify-center  { justify-content: center; }
.gap-2      { gap: var(--sp-2); }
.gap-3      { gap: var(--sp-3); }
.gap-4      { gap: var(--sp-4); }
.gap-6      { gap: var(--sp-6); }
.flex-1     { flex: 1; }
.flex-wrap  { flex-wrap: wrap; }
.shrink-0   { flex-shrink: 0; }

/* ── Typography utilities ────────────────────────────────────── */
.text-xs    { font-size: var(--text-xs); }
.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); }
.text-4xl   { font-size: var(--text-4xl); }

.font-medium  { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold    { font-weight: 700; }

.text-1     { color: var(--text-1); }
.text-2     { color: var(--text-2); }
.text-3     { color: var(--text-3); }
.text-accent { color: var(--accent); }

.text-center { text-align: center; }
.text-right  { text-align: right; }
.truncate   { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.line-clamp-2 {
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.line-clamp-3 {
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ── Spacing utilities ───────────────────────────────────────── */
.mt-2  { margin-top: var(--sp-2); }
.mt-4  { margin-top: var(--sp-4); }
.mt-6  { margin-top: var(--sp-6); }
.mt-8  { margin-top: var(--sp-8); }
.mb-2  { margin-bottom: var(--sp-2); }
.mb-4  { margin-bottom: var(--sp-4); }
.mb-6  { margin-bottom: var(--sp-6); }
.mb-8  { margin-bottom: var(--sp-8); }
.p-4   { padding: var(--sp-4); }
.p-6   { padding: var(--sp-6); }
.p-8   { padding: var(--sp-8); }
.py-4  { padding-block: var(--sp-4); }
.py-6  { padding-block: var(--sp-6); }
.px-4  { padding-inline: var(--sp-4); }
.px-6  { padding-inline: var(--sp-6); }

/* ── Visibility ──────────────────────────────────────────────── */
.hidden  { display: none !important; }
.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;
}

@media (min-width: 768px) {
  .hide-mobile { display: block; }
}
@media (max-width: 767px) {
  .hide-mobile { display: none !important; }
}

/* ── Divider ─────────────────────────────────────────────────── */
.divider {
  height: 1px;
  background: var(--border);
  border: none;
  margin-block: var(--sp-6);
}

/* ── Glass utility ───────────────────────────────────────────── */
.glass {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.glass:hover {
  background: var(--glass-hover);
}

/* ── Gradient text ───────────────────────────────────────────── */
.gradient-text {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-hover) 50%, #a78bfa 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ── Loading overlay ─────────────────────────────────────────── */
.page-loader {
  position: fixed;
  inset: 0;
  background: var(--bg-page);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity var(--t-slow), visibility var(--t-slow);
}

.page-loader.loaded {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.page-loader-spinner {
  width: 36px;
  height: 36px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

/* ── Main content wrapper ────────────────────────────────────── */
.main-content {
  min-height: calc(100dvh - var(--nav-h) - 200px);
  padding-top: var(--nav-h);
}

/* ── Aspect ratios ───────────────────────────────────────────── */
.aspect-video { aspect-ratio: 16/9; }
.aspect-square { aspect-ratio: 1/1; }
.aspect-card  { aspect-ratio: 16/9; }

/* ── Overflow ────────────────────────────────────────────────── */
.overflow-hidden { overflow: hidden; }

/* ── Object fit ──────────────────────────────────────────────── */
.object-cover { object-fit: cover; }
.w-full       { width: 100%; }
.h-full       { height: 100%; }

/* ── Rounded ─────────────────────────────────────────────────── */
.rounded-sm   { border-radius: var(--r-sm); }
.rounded-md   { border-radius: var(--r-md); }
.rounded-lg   { border-radius: var(--r-lg); }
.rounded-xl   { border-radius: var(--r-xl); }
.rounded-full { border-radius: var(--r-full); }

/* ── Accent colour dot ───────────────────────────────────────── */
.dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
}

.dot-success { background: var(--success); }
.dot-warning { background: var(--warning); }
.dot-danger  { background: var(--danger); }