/* Hanjie — washi paper, sumi ink, vermilion seal */
:root {
  --paper: #f6f1e7;
  --paper-2: #efe7d8;
  --card: #fbf8f2;
  --ink: #1d1a17;
  --ink-soft: #645b50;
  --ink-faint: #9a8f80;
  --line: #ddd3c2;
  --line-strong: #a39784;
  --accent: #d2402e;
  --accent-dark: #a92f20;
  --accent-soft: #f7ddd5;
  --ok: #3e7b4f;
  --ok-soft: #dcebdc;
  --warn: #b7791f;
  --warn-soft: #f6e7c8;
  --cell-bg: #fffdf8;
  --cell-fill: #1d1a17;
  --cell-hover: #f3ead9;
  --cell-hl: #f1e6d0;
  --clue-done: #b9ae9d;
  --shadow: 0 1px 2px rgba(60, 40, 20, .06), 0 6px 24px rgba(60, 40, 20, .07);
  --radius: 14px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-round: ui-rounded, "SF Pro Rounded", "Hiragino Maru Gothic ProN", "Nunito", "Segoe UI", system-ui, sans-serif;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #171512; --paper-2: #201d19; --card: #1e1b17;
    --ink: #efe8dc; --ink-soft: #b4a998; --ink-faint: #7b7266;
    --line: #36312b; --line-strong: #6a6155;
    --accent: #e3533f; --accent-dark: #f06b57; --accent-soft: #3a211b;
    --ok: #7cc08e; --ok-soft: #1f3324; --warn: #e0a64a; --warn-soft: #3a2e17;
    --cell-bg: #26221d; --cell-fill: #ebe2d2; --cell-hover: #312c25; --cell-hl: #2e2922;
    --clue-done: #5a5248;
    --shadow: 0 1px 2px rgba(0,0,0,.3), 0 6px 24px rgba(0,0,0,.25);
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #171512; --paper-2: #201d19; --card: #1e1b17;
  --ink: #efe8dc; --ink-soft: #b4a998; --ink-faint: #7b7266;
  --line: #36312b; --line-strong: #6a6155;
  --accent: #e3533f; --accent-dark: #f06b57; --accent-soft: #3a211b;
  --ok: #7cc08e; --ok-soft: #1f3324; --warn: #e0a64a; --warn-soft: #3a2e17;
  --cell-bg: #26221d; --cell-fill: #ebe2d2; --cell-hover: #312c25; --cell-hl: #2e2922;
  --clue-done: #5a5248;
  --shadow: 0 1px 2px rgba(0,0,0,.3), 0 6px 24px rgba(0,0,0,.25);
  color-scheme: dark;
}

* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--paper);
  background-image: radial-gradient(circle at 1px 1px, rgba(120, 100, 70, .07) 1px, transparent 0);
  background-size: 22px 22px;
  color: var(--ink); font: 16px/1.5 var(--font); min-height: 100vh;
  display: flex; flex-direction: column;
}
a { color: var(--accent-dark); }
h1, h2, h3 { font-family: var(--font-round); line-height: 1.2; margin: 0 0 .5em; letter-spacing: -.01em; }
h1 { font-size: 1.7rem; }
h2 { font-size: 1.25rem; }
h3 { font-size: 1.05rem; }
p { margin: 0 0 1em; }
.muted { color: var(--ink-soft); }
.small { font-size: .875rem; }
.hidden { display: none !important; }
@media (max-width: 520px) { .wide-only { display: none; } }

/* Header */
.site-header {
  display: flex; align-items: center; gap: 16px; flex-wrap: wrap;
  padding: 14px 24px; border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(6px); position: sticky; top: 0; z-index: 20;
}
.brand { display: flex; align-items: center; text-decoration: none; }
.brand img { height: 34px; display: block; }
.brand .logo-dark { display: none; }
:root[data-theme="dark"] .brand .logo-light { display: none; }
:root[data-theme="dark"] .brand .logo-dark { display: block; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .brand .logo-light { display: none; }
  :root:not([data-theme="light"]) .brand .logo-dark { display: block; }
}
.nav { display: flex; gap: 4px; margin-left: auto; }
.nav a {
  text-decoration: none; color: var(--ink-soft); font-weight: 600; font-size: .95rem;
  padding: 8px 14px; border-radius: 999px;
}
.nav a:hover { background: var(--paper-2); color: var(--ink); }
.nav a[aria-current="page"] { background: var(--ink); color: var(--paper); }

main { flex: 1; width: 100%; max-width: 1180px; margin: 0 auto; padding: 24px; }
.site-footer { text-align: center; padding: 18px; color: var(--ink-faint); font-size: .8rem; }
.site-footer a { color: inherit; }

/* Controls */
.btn {
  appearance: none; border: 1px solid var(--line-strong); background: var(--card); color: var(--ink);
  font: 600 .92rem/1 var(--font); padding: 10px 16px; border-radius: 10px; cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center; gap: 8px; text-decoration: none;
  transition: background .12s, border-color .12s, transform .06s;
}
.btn:hover { background: var(--paper-2); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: .5; cursor: not-allowed; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { background: var(--accent-dark); border-color: var(--accent-dark); }
.btn.ghost { background: transparent; border-color: transparent; }
.btn.ghost:hover { background: var(--paper-2); }
.btn.danger { color: var(--accent-dark); }
.btn.sm { padding: 7px 11px; font-size: .84rem; border-radius: 8px; }
.btn svg { width: 18px; height: 18px; flex: none; }
.btn[aria-pressed="true"] { background: var(--ink); color: var(--paper); border-color: var(--ink); }

.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 20px; }

label.field { display: block; margin-bottom: 14px; }
label.field > span { display: block; font-weight: 600; font-size: .88rem; margin-bottom: 6px; }
input[type="text"], input[type="password"], select {
  width: 100%; font: inherit; color: var(--ink); background: var(--cell-bg);
  border: 1px solid var(--line-strong); border-radius: 9px; padding: 9px 11px;
}
input:focus-visible, select:focus-visible, .btn:focus-visible, a:focus-visible { outline: 3px solid color-mix(in srgb, var(--accent) 45%, transparent); outline-offset: 2px; }
input[type="range"] { width: 100%; accent-color: var(--accent); }
input[type="checkbox"] { accent-color: var(--accent); width: 18px; height: 18px; flex: none; }

.seg { display: inline-flex; background: var(--paper-2); border-radius: 10px; padding: 3px; gap: 2px; flex-wrap: wrap; }
.seg button {
  border: 0; background: transparent; color: var(--ink-soft); font: 600 .86rem var(--font);
  padding: 7px 12px; border-radius: 8px; cursor: pointer;
}
.seg button[aria-pressed="true"] { background: var(--card); color: var(--ink); box-shadow: 0 1px 3px rgba(0,0,0,.12); }

.toast {
  position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%) translateY(20px);
  background: var(--ink); color: var(--paper); padding: 11px 18px; border-radius: 10px;
  font-weight: 600; font-size: .92rem; opacity: 0; pointer-events: none; transition: .2s; z-index: 100;
  max-width: calc(100vw - 32px);
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
.toast.error { background: var(--accent-dark); color: #fff; }

.badge { display: inline-block; font-size: .72rem; font-weight: 700; letter-spacing: .02em; padding: 3px 8px; border-radius: 999px; background: var(--paper-2); color: var(--ink-soft); }
.badge.Easy { background: var(--ok-soft); color: var(--ok); }
.badge.Medium { background: var(--warn-soft); color: var(--warn); }
.badge.Hard, .badge.Expert { background: var(--accent-soft); color: var(--accent-dark); }

/* Modal */
.modal-back {
  position: fixed; inset: 0; background: rgba(20, 15, 10, .45); display: flex; align-items: center; justify-content: center;
  padding: 16px; z-index: 50; animation: fade .2s;
}
.modal { background: var(--card); border-radius: 18px; box-shadow: var(--shadow); padding: 28px; width: min(440px, 100%); text-align: center; max-height: calc(100vh - 32px); overflow: auto; }
@keyframes fade { from { opacity: 0; } }

@media (max-width: 520px) {
  .brand img.logo-light, .brand img.logo-dark { display: none !important; }
  .brand::before { content: ""; width: 34px; height: 34px; background: url(logo-mark.svg) center / contain no-repeat; display: block; }
  .nav { margin-left: auto; }
  .studio-tag { display: none; }
}
@media (max-width: 640px) {
  .site-header { padding: 10px 16px; gap: 10px; flex-wrap: nowrap; }
  .brand img { height: 28px; }
  .nav a { padding: 7px 10px; font-size: .88rem; }
  main { padding: 16px; }
}