/* =========================================================================
   N VoaWu — base.css
   Reset, typography, container, grid, link/button styles, forms, a11y.
   ========================================================================= */

*,
*::before,
*::after {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--fs-base);
  line-height: var(--lh-loose);
  color: var(--text-primary);
  background: var(--bg-page);
  min-height: 100vh;
  overflow-x: hidden;
}

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

img {
  font-style: italic; /* alt-text styling */
}

button {
  font-family: inherit;
  font-size: inherit;
  cursor: pointer;
  border: 0;
  background: transparent;
  color: inherit;
}

a {
  color: var(--color-accent-600);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-standard);
}

a:hover {
  color: var(--color-accent-700);
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
summary:focus-visible,
[tabindex]:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: var(--radius-xs);
}

::selection {
  background: var(--color-accent-300);
  color: var(--color-ink-900);
}

/* ---------- Layout containers ---------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding-inline: var(--container-pad);
}

.section {
  padding-block: var(--section-pad-y);
  position: relative;
}

.section--alt {
  background: var(--bg-mist);
}

.section--dark {
  background: var(--bg-inverse);
  color: var(--text-inverse);
}

.section--gradient {
  background: var(--gradient-mesh-cool);
  color: var(--text-inverse);
}

.section__head {
  max-width: 56ch;
  margin-bottom: var(--space-8);
}

.section__eyebrow {
  display: inline-block;
  font-family: var(--font-display);
  font-size: var(--fs-xs);
  font-weight: var(--fw-semibold);
  letter-spacing: var(--tracking-wider);
  text-transform: uppercase;
  color: var(--color-accent-600);
  margin-bottom: var(--space-3);
  padding: 0.25rem 0.75rem;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-pill);
  background: var(--bg-surface);
}

.section--dark .section__eyebrow,
.section--gradient .section__eyebrow {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.18);
  color: var(--color-accent-300);
}

.section__title {
  font-family: var(--font-display);
  font-size: var(--fs-3xl);
  font-weight: var(--fw-bold);
  line-height: var(--lh-tight);
  letter-spacing: var(--tracking-tight);
  margin: 0 0 var(--space-4);
  color: inherit;
}

.section__lead {
  font-size: var(--fs-md);
  color: var(--text-secondary);
  margin: 0;
  line-height: var(--lh-loose);
}

.section--dark .section__lead,
.section--gradient .section__lead {
  color: var(--color-silver-300);
}

/* ---------- Typography ---------- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: var(--fw-bold);
  line-height: var(--lh-tight);
  letter-spacing: var(--tracking-tight);
  color: inherit;
  margin: 0 0 var(--space-4);
}

h1 {
  font-size: var(--fs-4xl);
}

h2 {
  font-size: var(--fs-3xl);
}

h3 {
  font-size: var(--fs-xl);
  letter-spacing: var(--tracking-normal);
}

h4 {
  font-size: var(--fs-lg);
  letter-spacing: var(--tracking-normal);
}

p {
  margin: 0 0 var(--space-4);
}

ul, ol {
  padding-left: 1.25rem;
  margin: 0 0 var(--space-4);
}

li + li {
  margin-top: 0.35rem;
}

code, kbd, samp, pre {
  font-family: var(--font-mono);
  font-size: 0.95em;
}

hr {
  border: 0;
  height: 1px;
  background: var(--border-subtle);
  margin: var(--space-7) 0;
}

::placeholder {
  color: var(--text-muted);
  opacity: 1;
}

/* ---------- Skip link ---------- */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  background: var(--color-ink-900);
  color: var(--color-pure);
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius-sm);
  z-index: var(--z-skip);
  font-weight: var(--fw-semibold);
  transition: top var(--dur-fast) var(--ease-standard);
}

.skip-link:focus {
  top: 1rem;
  color: var(--color-pure);
}

/* ---------- Visually hidden ---------- */
.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;
}

/* ---------- Forms ---------- */
.form {
  display: grid;
  gap: var(--space-5);
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.field__label {
  font-size: var(--fs-sm);
  font-weight: var(--fw-semibold);
  color: var(--text-primary);
  letter-spacing: 0.01em;
}

.field__hint {
  font-size: var(--fs-xs);
  color: var(--text-muted);
  margin-top: 0.2rem;
}

.field__error {
  font-size: var(--fs-xs);
  color: var(--color-danger);
  margin-top: 0.2rem;
  min-height: 1.1em;
}

.input,
.select,
.textarea {
  width: 100%;
  font: inherit;
  color: var(--text-primary);
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 0.85rem 1rem;
  transition: border-color var(--dur-fast) var(--ease-standard),
              box-shadow var(--dur-fast) var(--ease-standard),
              background var(--dur-fast) var(--ease-standard);
}

.input:hover,
.select:hover,
.textarea:hover {
  border-color: var(--color-accent-500);
}

.input:focus,
.select:focus,
.textarea:focus {
  outline: none;
  border-color: var(--color-accent-600);
  box-shadow: 0 0 0 4px var(--color-accent-100);
}

.textarea {
  min-height: 9rem;
  resize: vertical;
}

.select {
  appearance: none;
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%234A5063' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.85rem center;
  background-size: 1rem;
  padding-right: 2.4rem;
}

.checkbox {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  font-size: var(--fs-sm);
  color: var(--text-secondary);
  line-height: 1.5;
}

.checkbox input {
  margin-top: 0.25rem;
  width: 1.1rem;
  height: 1.1rem;
  accent-color: var(--color-accent-600);
}

.form__actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  flex-wrap: wrap;
}

.form__status {
  font-size: var(--fs-sm);
  color: var(--color-success);
  display: none;
  align-items: center;
  gap: 0.4rem;
}

.form__status.is-visible {
  display: inline-flex;
}

.form__status.is-error {
  color: var(--color-danger);
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}