frontend/src/styles/base.css

/* ---------------------------------------------------------------------------
   Base — reset, typography, forms, focus, motion safety.
--------------------------------------------------------------------------- */

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

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  transition: background-color var(--dur-2) var(--ease-out), color var(--dur-2) var(--ease-out);
}

h1, h2, h3, h4 {
  margin: 0;
  line-height: 1.18;
  letter-spacing: -0.018em;
  font-weight: 700;
  text-wrap: balance;
}

p {
  margin: 0;
}

img {
  max-width: 100%;
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}

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

code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--code-bg);
  color: var(--code-ink);
  padding: 0.14rem 0.42rem;
  border-radius: var(--r-sm);
}

pre {
  overflow: auto;
  white-space: pre-wrap;
  padding: var(--s-4);
  border-radius: var(--r-md);
  border: 1px solid var(--line);
  background: var(--surface-2);
  color: var(--ink-2);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
}

pre code {
  background: none;
  padding: 0;
  color: inherit;
}

hr {
  border: 0;
  border-top: 1px solid var(--line);
  margin: var(--s-5) 0;
}

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

label {
  display: block;
  margin: var(--s-4) 0 var(--s-1);
  color: var(--ink-2);
  font-size: var(--text-sm);
  font-weight: 550;
}

input:not([type="file"]),
textarea,
select {
  width: 100%;
  border: 1px solid var(--line-input);
  border-radius: var(--r-md);
  padding: 0.62rem 0.78rem;
  background: var(--surface);
  color: var(--ink);
  transition: border-color var(--dur-1) var(--ease-out), box-shadow var(--dur-1) var(--ease-out);
}

input::placeholder,
textarea::placeholder {
  color: var(--ink-3);
  opacity: 1;
}

input:hover:not(:disabled):not(:focus),
textarea:hover:not(:disabled):not(:focus) {
  border-color: var(--ink-2);
}

/* Keep inputs at ≥16px on small screens so iOS Safari doesn't zoom on focus. */
@media (max-width: 880px) {
  input:not([type="file"]),
  textarea,
  select {
    font-size: max(1rem, var(--text-base));
  }
}

input:focus,
textarea:focus,
select:focus {
  outline: none;
  border-color: var(--focus);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--focus) 22%, transparent);
}

input[aria-invalid="true"],
textarea[aria-invalid="true"] {
  border-color: var(--danger);
}

input[aria-invalid="true"]:focus,
textarea[aria-invalid="true"]:focus {
  border-color: var(--danger);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--danger) 22%, transparent);
}

input:disabled,
textarea:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

textarea {
  min-height: 6.4rem;
  resize: vertical;
}

::selection {
  background: var(--accent-soft);
  color: var(--accent-on-soft);
}

/* Visible, high-contrast keyboard focus everywhere. */
:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
  border-radius: var(--r-sm);
}

/* <main> receives programmatic focus on route changes (for screen readers);
   that focus is not a keyboard affordance, so it draws no ring. */
main:focus {
  outline: none;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}