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

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

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.75;
  color: var(--ink);
  background-color: var(--paper);
  background-image: repeating-linear-gradient(
    to bottom,
    transparent 0,
    transparent calc(2.4rem - 1px),
    var(--rule-line) calc(2.4rem - 1px),
    var(--rule-line) 2.4rem
  );
}

h1, h2, h3, h4 {
  line-height: 1.35;
  margin: 0;
  font-weight: 700;
}

p {
  margin: 0;
}

a {
  color: var(--pine);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

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

button {
  font: inherit;
  cursor: pointer;
}

:focus-visible {
  outline: 3px solid var(--pine);
  outline-offset: 2px;
  border-radius: 2px;
}

.wrap {
  width: min(var(--wrap), 100% - var(--sp-5) * 2);
  margin-inline: auto;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: 0.55rem 1.15rem;
  border: 1px solid var(--ink);
  border-radius: var(--radius-s);
  background: var(--surface);
  color: var(--ink);
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  transition: transform 120ms ease, box-shadow 120ms ease, background-color 120ms ease;
}

.btn:hover { box-shadow: var(--shadow-sticker); transform: translate(1px, -1px); }
.btn:active { box-shadow: none; transform: none; }
.btn[disabled] { opacity: 0.55; cursor: not-allowed; box-shadow: none; transform: none; }

.btn--primary {
  background: var(--pine-solid);
  border-color: var(--pine-deep);
  color: #fffdf8;
}
.btn--primary:hover { background: var(--pine-deep); }

.btn--danger {
  background: var(--danger-tint);
  border-color: var(--danger);
  color: var(--danger);
}
.btn--danger:hover { background: var(--danger); color: #fffdf8; }

.btn--ghost {
  border-color: transparent;
  background: transparent;
  color: var(--ink-soft);
}
.btn--ghost:hover { box-shadow: none; transform: none; color: var(--ink); }

.btn--sm { padding: 0.3rem 0.7rem; font-size: 0.85rem; }

/* ---------- form fields ---------- */

.field {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  margin-bottom: var(--sp-4);
}

.field > label {
  font-weight: 600;
  font-size: 0.92rem;
}

.field .hint {
  font-size: 0.82rem;
  color: var(--ink-faint);
}

.field input,
.field textarea,
.field select {
  font: inherit;
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-s);
  background: var(--surface);
  color: var(--ink);
}

.field input:focus-visible,
.field textarea:focus-visible,
.field select:focus-visible {
  outline: 3px solid var(--pine);
  outline-offset: 1px;
}

.field__error {
  color: var(--danger);
  font-size: 0.85rem;
  font-weight: 500;
}

/* ---------- status chips ---------- */

.chip {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.12rem 0.6rem;
  border: 1px solid currentColor;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 700;
  white-space: nowrap;
}

.chip[data-tone="danger"] { color: var(--danger); background: var(--danger-tint); }
.chip[data-tone="urgent"] { color: var(--urgent); background: var(--urgent-tint); }
.chip[data-tone="warn"]   { color: var(--warn); background: var(--warn-tint); }
.chip[data-tone="calm"]   { color: var(--calm); background: var(--calm-tint); }
.chip[data-tone="exam"]   { color: var(--exam); background: var(--exam-tint); }
.chip[data-tone="neutral"] { color: var(--ink-soft); background: var(--paper-deep); }

.subject-tag {
  display: inline-block;
  padding: 0.08rem 0.55rem;
  background: var(--paper-deep);
  border-inline-start: 3px solid var(--accent, var(--pine));
  border-radius: 3px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--ink-soft);
}

/* ---------- async states ---------- */

.skeleton {
  border-radius: var(--radius-s);
  background: linear-gradient(90deg, #e7e2d5 25%, #f0ece1 50%, #e7e2d5 75%);
  background-size: 200% 100%;
  animation: shimmer 1.3s infinite linear;
}

[data-theme="dark"] .skeleton {
  background: linear-gradient(90deg, #2b303b 25%, #353b48 50%, #2b303b 75%);
}

@keyframes shimmer {
  from { background-position: 200% 0; }
  to { background-position: -200% 0; }
}

@media (prefers-reduced-motion: reduce) {
  .skeleton { animation: none; }
  .btn, .chip { transition: none; }
}

.state {
  text-align: center;
  padding: var(--sp-7) var(--sp-4);
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius-m);
  background: var(--surface);
  color: var(--ink-soft);
}

.state svg { margin-inline: auto; margin-bottom: var(--sp-3); opacity: 0.6; }
.state__title { font-weight: 700; font-size: 1.05rem; color: var(--ink); margin-bottom: var(--sp-1); }
.state__hint { font-size: 0.9rem; margin-bottom: var(--sp-4); }

.state--error { border-style: solid; border-color: var(--danger); background: var(--danger-tint); }
.state--error .state__title { color: var(--danger); }

/* ---------- misc ---------- */

.page-note {
  color: var(--ink-faint);
  font-size: 0.85rem;
}

/* round icon-only button (theme toggle etc.) */
.icon-btn {
  display: inline-grid;
  place-items: center;
  width: 2.3rem;
  height: 2.3rem;
  padding: 0;
  border: none;
  border-radius: 50%;
  background: transparent;
  color: inherit;
}

.icon-btn:hover { background: rgba(128, 128, 128, 0.18); }