/* ============================================
   Border Pet – Global Stylesheet
   Inspired by GOV.UK Design System
   ============================================ */

/* --- Google Fonts import --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

/* --- CSS Custom Properties --- */
:root {
  /* Brand colours */
  --color-primary:    #454ADE;
  --color-black:      #1B1F3B;
  --color-white:      #EBEBEB;
  --color-secondary:  #CD533B;
  --color-lighter:    #FF934F;

  /* Functional colours */
  --color-text:          var(--color-black);
  --color-background:    #ffffff;
  --color-surface:       var(--color-white);
  --color-link:          var(--color-primary);
  --color-link-visited:  #7b3f9e;         /* WCAG-compliant purple */
  --color-link-hover:    #2d31a6;
  --color-link-active:   var(--color-black);
  --color-focus:         #ffbf47;         /* GOV.UK-style yellow focus ring */
  --color-focus-text:    var(--color-black);
  --color-border:        #b1b4b6;
  --color-error:         var(--color-secondary);
  --color-success:       #00703c;

  /* Typography */
  --font-family:     'Inter', arial, sans-serif;
  --font-size-base:  19px;               /* GOV.UK body size */
  --font-size-sm:    16px;
  --font-size-xs:    14px;
  --line-height:     1.5;

  /* Spacing scale */
  --space-1:   4px;
  --space-2:   8px;
  --space-3:  12px;
  --space-4:  16px;
  --space-5:  24px;
  --space-6:  32px;
  --space-7:  48px;
  --space-8:  64px;

  /* Layout */
  --max-width:    960px;
  --border-radius: 0;                    /* GOV.UK uses square corners */
}

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

html {
  font-size: var(--font-size-base);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  font-size: 1rem;
  line-height: var(--line-height);
  color: var(--color-text);
  background-color: var(--color-background);
  -webkit-font-smoothing: antialiased;
}

/* --- Skip link (accessibility) --- */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  padding: var(--space-2) var(--space-4);
  background: var(--color-focus);
  color: var(--color-focus-text);
  font-weight: 700;
  font-size: var(--font-size-sm);
  text-decoration: none;
  z-index: 9999;
}

.skip-link:focus {
  top: var(--space-4);
}

/* --- Focus (WCAG 2.1 AA) --- */
:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 0;
  background-color: var(--color-focus);
  color: var(--color-focus-text);
  box-shadow: 0 -2px var(--color-focus), 0 4px var(--color-focus-text);
  text-decoration: none;
}

/* Remove default focus ring where :focus-visible is supported */
:focus:not(:focus-visible) {
  outline: none;
}

/* --- Links — GOV.UK style --- */
a:link {
  color: var(--color-link);
  text-decoration: underline;
  text-underline-offset: 2px;
  text-decoration-thickness: 1px;
}

a:visited {
  color: var(--color-link-visited);
}

a:hover {
  color: var(--color-link-hover);
  text-decoration-thickness: 3px;
}

a:active {
  color: var(--color-link-active);
}

a:focus-visible {
  color: var(--color-focus-text);
  background-color: var(--color-focus);
  outline: 3px solid var(--color-focus);
  text-decoration: none;
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-family);
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

h1 { font-size: clamp(2rem, 4vw, 3rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.25rem); }
h3 { font-size: clamp(1.25rem, 2.5vw, 1.75rem); }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

p {
  margin-bottom: var(--space-5);
  max-width: 66ch; /* improves readability */
}

strong, b { font-weight: 700; }

/* --- Layout --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-5);
}

/* --- Header --- */
.site-header {
  background-color: var(--color-primary);
  padding: var(--space-4) 0;
  border-bottom: 4px solid var(--color-black);
}

.site-header a {
  color: var(--color-white);
  text-decoration: none;
  font-weight: 700;
  font-size: 1.25rem;
}

.site-header a:visited {
  color: var(--color-white);
}

.site-header a:hover {
  text-decoration: underline;
  text-decoration-thickness: 3px;
}

/* --- Navigation --- */
.nav {
  background-color: var(--color-black);
  padding: var(--space-2) 0;
}

.nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
}

.nav a {
  display: inline-block;
  padding: var(--space-2) var(--space-3);
  color: var(--color-white);
  text-decoration: none;
  font-size: var(--font-size-sm);
  font-weight: 500;
}

.nav a:visited { color: var(--color-white); }

.nav a:hover {
  background-color: rgba(255, 255, 255, 0.1);
  text-decoration: underline;
}

.nav a[aria-current="page"] {
  background-color: var(--color-primary);
  color: var(--color-white);
}

/* --- Main content --- */
main {
  padding: var(--space-7) 0;
}

/* --- Breadcrumbs --- */
.breadcrumbs {
  font-size: var(--font-size-sm);
  margin-bottom: var(--space-5);
  color: var(--color-border);
}

.breadcrumbs ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
}

.breadcrumbs li + li::before {
  content: '›';
  margin-right: var(--space-1);
  color: var(--color-border);
}

/* --- Buttons --- */
.btn {
  display: inline-block;
  padding: var(--space-2) var(--space-5);
  font-family: var(--font-family);
  font-size: 1rem;
  font-weight: 700;
  text-decoration: none;
  text-align: center;
  cursor: pointer;
  border: none;
  border-radius: var(--border-radius);
  box-shadow: 0 3px 0 rgba(0,0,0,0.25);
  transition: background-color 0.1s ease;
}

.btn:active {
  box-shadow: none;
  transform: translateY(2px);
}

.btn-primary {
  background-color: var(--color-primary);
  color: #ffffff;
}

.btn-primary:visited { color: #ffffff; }

.btn-primary:hover {
  background-color: var(--color-link-hover);
  text-decoration: none;
}

.btn-secondary {
  background-color: var(--color-white);
  color: var(--color-black);
  border: 2px solid var(--color-black);
  box-shadow: none;
}

.btn-secondary:hover {
  background-color: #d4d4d4;
}

.btn-warning {
  background-color: var(--color-secondary);
  color: #ffffff;
}

.btn-warning:visited { color: #ffffff; }

.btn-warning:hover {
  background-color: #a8432f;
}

/* --- Inset / callout --- */
.inset {
  border-left: 5px solid var(--color-primary);
  padding: var(--space-4) var(--space-5);
  background-color: var(--color-surface);
  margin-bottom: var(--space-5);
}

.inset--warning {
  border-left-color: var(--color-secondary);
}

.inset--success {
  border-left-color: var(--color-success);
}

/* --- Warning banner --- */
.warning-banner {
  background-color: var(--color-lighter);
  color: var(--color-black);
  padding: var(--space-4) var(--space-5);
  border-left: 5px solid var(--color-secondary);
  font-weight: 600;
  margin-bottom: var(--space-5);
}

/* --- Tag / badge --- */
.tag {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  font-size: var(--font-size-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background-color: var(--color-primary);
  color: #ffffff;
}

.tag--secondary {
  background-color: var(--color-secondary);
}

/* --- Forms --- */
label {
  display: block;
  font-weight: 600;
  margin-bottom: var(--space-1);
}

input[type="text"],
input[type="email"],
input[type="search"],
select,
textarea {
  display: block;
  width: 100%;
  padding: var(--space-2) var(--space-3);
  font-family: var(--font-family);
  font-size: 1rem;
  color: var(--color-text);
  background-color: #ffffff;
  border: 2px solid var(--color-black);
  border-radius: var(--border-radius);
  appearance: none;
}

input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 0;
  border-color: var(--color-focus-text);
}

.form-group {
  margin-bottom: var(--space-5);
}

.hint {
  font-size: var(--font-size-sm);
  color: #555e6a;
  margin-bottom: var(--space-2);
}

.error-message {
  font-weight: 700;
  color: var(--color-error);
  margin-bottom: var(--space-2);
}

input.error,
select.error,
textarea.error {
  border-color: var(--color-error);
  border-width: 3px;
}

/* --- Tables --- */
table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--font-size-sm);
  margin-bottom: var(--space-5);
}

th {
  text-align: left;
  padding: var(--space-3) var(--space-4);
  background-color: var(--color-black);
  color: var(--color-white);
  font-weight: 700;
}

td {
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-border);
}

tr:nth-child(even) td {
  background-color: var(--color-surface);
}

/* --- Footer --- */
.site-footer {
  background-color: var(--color-black);
  color: var(--color-white);
  padding: var(--space-7) 0;
  margin-top: var(--space-8);
  font-size: var(--font-size-sm);
}

.site-footer a {
  color: var(--color-white);
}

.site-footer a:visited {
  color: #c4c4d4;
}

.site-footer a:hover {
  text-decoration-thickness: 3px;
}

.site-footer hr {
  border: none;
  border-top: 1px solid rgba(255,255,255,0.2);
  margin: var(--space-5) 0;
}

/* --- Utility classes --- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.text-center { text-align: center; }
.text-right  { text-align: right; }

.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }
.mb-4 { margin-bottom: var(--space-4); }
.mb-5 { margin-bottom: var(--space-5); }
.mb-6 { margin-bottom: var(--space-6); }

/* --- Responsive --- */
@media (max-width: 640px) {
  :root {
    --font-size-base: 16px;
  }

  .container {
    padding: 0 var(--space-4);
  }

  .nav ul {
    flex-direction: column;
    gap: 0;
  }

  .btn {
    width: 100%;
    display: block;
  }

  table {
    display: block;
    overflow-x: auto;
  }
}

/* --- Print --- */
@media print {
  .site-header,
  .site-footer,
  .nav,
  .btn { display: none; }

  a::after {
    content: ' (' attr(href) ')';
    font-size: 0.85em;
    color: #555;
  }

  body { font-size: 12pt; color: #000; }
}