@import url('https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,300;0,400;0,500;0,700;1,400&family=Roboto+Mono:wght@400;500&display=swap');

/* ================================== */
/* Material Design 3 — Design Tokens  */
/* https://m3.material.io/            */
/* ================================== */

/* Light scheme (M3 baseline) */
:root {
  /* Color roles */
  --md-primary: #6750A4;
  --md-on-primary: #FFFFFF;
  --md-primary-container: #EADDFF;
  --md-on-primary-container: #21005D;

  --md-secondary: #625B71;
  --md-on-secondary: #FFFFFF;
  --md-secondary-container: #E8DEF8;
  --md-on-secondary-container: #1D192B;

  --md-tertiary: #7D5260;
  --md-on-tertiary: #FFFFFF;
  --md-tertiary-container: #FFD8E4;
  --md-on-tertiary-container: #31111D;

  --md-surface: #FEF7FF;
  --md-on-surface: #1D1B20;
  --md-surface-variant: #E7E0EC;
  --md-on-surface-variant: #49454F;
  --md-surface-container-low: #F7F2FA;
  --md-surface-container: #F3EDF7;
  --md-surface-container-high: #ECE6F0;
  --md-surface-container-highest: #E6E0E9;

  --md-outline: #79747E;
  --md-outline-variant: #CAC4D0;

  /* Elevation shadows */
  --md-elevation-1: 0 1px 2px rgba(0, 0, 0, 0.3), 0 1px 3px 1px rgba(0, 0, 0, 0.15);
  --md-elevation-2: 0 1px 2px rgba(0, 0, 0, 0.3), 0 2px 6px 2px rgba(0, 0, 0, 0.15);

  /* Shape scale */
  --md-shape-xs: 4px;
  --md-shape-sm: 8px;
  --md-shape-md: 12px;
  --md-shape-lg: 16px;
  --md-shape-xl: 28px;
  --md-shape-full: 9999px;

  /* State layer opacities */
  --md-state-hover: 8%;
  --md-state-focus: 10%;

  /* ---- Legacy aliases (keep old names working) ---- */
  --active: var(--md-primary);
  --author: var(--md-tertiary);
  --bg: var(--md-surface);
  --nav: var(--md-surface-container);
  --color: var(--md-on-surface);
}

/* Dark scheme (M3 baseline) — still doesn't attract bugs */
[data-theme="dark"] {
  --md-primary: #D0BCFF;
  --md-on-primary: #381E72;
  --md-primary-container: #4F378B;
  --md-on-primary-container: #EADDFF;

  --md-secondary: #CCC2DC;
  --md-on-secondary: #332D41;
  --md-secondary-container: #4A4458;
  --md-on-secondary-container: #E8DEF8;

  --md-tertiary: #EFB8C8;
  --md-on-tertiary: #492532;
  --md-tertiary-container: #633B48;
  --md-on-tertiary-container: #FFD8E4;

  --md-surface: #141218;
  --md-on-surface: #E6E0E9;
  --md-surface-variant: #49454F;
  --md-on-surface-variant: #CAC4D0;
  --md-surface-container-low: #1D1B20;
  --md-surface-container: #211F26;
  --md-surface-container-high: #2B2930;
  --md-surface-container-highest: #36343B;

  --md-outline: #938F99;
  --md-outline-variant: #49454F;
}

/* ============== */
/* Base           */
/* ============== */

body {
  /* M3 body-large */
  font-family: Roboto, system-ui, sans-serif;
  font-size: 16px;
  line-height: 24px;
  letter-spacing: 0.5px;

  background-color: var(--md-surface);
  color: var(--md-on-surface);
  padding-bottom: 500px;
  margin: 0;
}

h1, h2, h3 {
  color: var(--md-on-surface);
  font-weight: 400; /* M3 headlines are regular weight */
}

h1 { font-size: 32px; line-height: 40px; }  /* headline-large */
h2 { font-size: 28px; line-height: 36px; }  /* headline-medium */
h3 { font-size: 24px; line-height: 32px; }  /* headline-small */

/* ============== */
/* Webpage Content */
/* ============== */

main {
  margin-left: 450px;
  margin-right: 450px;
  margin-top: 90px;
}

/* ============== */
/* Navigation (M3 top app bar) */
/* ============== */

nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  box-sizing: border-box;

  display: flex;
  align-items: center;
  gap: 2rem;
  padding: 0.75rem 1.5rem;

  background: var(--md-surface-container);
  color: var(--md-on-surface);
  box-shadow: var(--md-elevation-2);
  /* M3 surfaces don't use hard borders — elevation separates them */
}

nav ul {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
}

/* Nav items — pill-shaped, with M3 state layers */
nav ul a,
nav ul button {
  /* M3 label-large */
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  line-height: 20px;
  letter-spacing: 0.1px;

  color: var(--md-on-surface-variant);
  text-decoration: none;
  padding: 0.5rem 1rem;
  border: none;
  border-radius: var(--md-shape-full);
  background: transparent;
  cursor: pointer;
  transition: background-color 0.2s ease, color 0.2s ease;
}

/* Hover: 8% on-surface state layer */
nav ul a:hover,
nav ul button:hover {
  background-color: color-mix(in srgb, var(--md-on-surface) var(--md-state-hover), transparent);
  color: var(--md-on-surface);
}

/* Focus: 10% state layer */
nav ul a:focus-visible,
nav ul button:focus-visible {
  background-color: color-mix(in srgb, var(--md-on-surface) var(--md-state-focus), transparent);
  outline: 2px solid var(--md-primary);
  outline-offset: 2px;
}

/* Active page: secondary container "selected" chip look */
nav ul a.active {
  background-color: var(--md-secondary-container);
  color: var(--md-on-secondary-container);
}

nav .site-title {
  /* M3 title-large — top app bar headline */
  font-size: 22px;
  line-height: 28px;
  font-weight: 400;
  text-decoration: none;
  color: var(--md-on-surface);
}

/* ============== */
/* Posts (M3 cards) */
/* ============== */

.post-list > * {
  margin: 24px 0;
}

.post-item {
  list-style-type: none;
  background-color: var(--md-surface-container-low);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--md-shape-md);
  padding: 16px 20px;
  transition: background-color 0.2s ease, box-shadow 0.2s ease;
}

.post-item:hover {
  box-shadow: var(--md-elevation-1);
  background-color: var(--md-surface-container);
}

.post-link {
  /* M3 title-medium */
  font-size: 20px;
  font-weight: 500;
  letter-spacing: 0.15px;
  text-decoration: none;
  color: var(--md-primary);
}

.post-link:hover {
  text-decoration: underline;
}

.post-author {
  color: var(--md-tertiary);
}

/* post metadata — M3 body-small */
.post-meta {
  font-size: 12px;
  line-height: 16px;
  letter-spacing: 0.4px;
  color: var(--md-on-surface-variant);
}

/* ============== */
/* Tags (M3 assist chips) */
/* ============== */

.tag {
  display: inline-block;
  font-size: 14px;
  font-weight: 500;
  color: var(--md-on-surface-variant);
  text-decoration: none;
  border: 1px solid var(--md-outline);
  border-radius: var(--md-shape-sm);
  padding: 4px 12px;
  transition: background-color 0.2s ease;
}

.tag:hover {
  background-color: color-mix(in srgb, var(--md-on-surface-variant) var(--md-state-hover), transparent);
}

.tags {
  padding: 12px;
  background-color: var(--md-surface-container);
  border-radius: var(--md-shape-md);
}

/* Hamburger — hidden on desktop */
#nav-toggle {
  display: none;
  color: var(--md-on-surface);
  background: none;
  border: none;
  border-radius: var(--md-shape-full);
  font-family: inherit;
  font-size: 1.3rem;
  padding: 0.4rem 0.7rem;
  cursor: pointer;
  margin-left: auto;
  transition: background-color 0.2s ease;
}

#nav-toggle:hover {
  background-color: color-mix(in srgb, var(--md-on-surface) var(--md-state-hover), transparent);
}

/* ============== */
/* Hyperlinks and Code */
/* ============== */

a {
  color: var(--md-primary);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--md-primary) 40%, transparent);
  transition: text-decoration-color 0.2s ease;
}

a:hover {
  text-decoration-color: var(--md-primary);
}

code {
  font-family: "Roboto Mono", monospace;
  font-size: 14px;
  padding: 2px 6px;
}

code:not([class]) {
  border-radius: var(--md-shape-xs);
  background: var(--md-surface-container-highest);
  color: var(--md-on-surface);
}

pre {
  background: var(--md-surface-container-high);
  border-radius: var(--md-shape-md);
  padding: 16px;
  overflow-x: auto;
}

/* ============== */
/* Mobile */
/* ============== */

@media (max-width: 768px) {
  #nav-toggle {
    display: block;
  }

  nav {
    flex-wrap: wrap;
    gap: 0.5rem;
    padding: 0.75rem 1rem;
  }

  nav ul {
    display: none;
    flex-direction: column;
    align-items: stretch;
    width: 100%;
    gap: 0.25rem;
    padding: 0.5rem 0;
  }

  nav ul.open {
    display: flex;
  }

  nav ul a,
  nav ul button {
    display: block;
    padding: 0.75rem 1rem;
    border-radius: var(--md-shape-full);
    text-align: left;
  }

  main {
    margin: 88px 1rem 0;
  }
}

/* Anchor highlight — primary container instead of a translucent wash */
:target {
  background: var(--md-primary-container);
  color: var(--md-on-primary-container);
  border-radius: var(--md-shape-sm);
}