/* Theme: colors are CSS variables so JS and dark mode share one palette. */
:root {
    color-scheme: light dark;
    --bg: #fff;
    --fg: #000;
    --grid-line: #000;
    --grid-line-thin: #888;
    --disabled: #b8b8b8;
    --accent: #0a85ff;
    --danger: #f00;
    --hyp: #0c5;
    --wrong: #f22;
    --selected-bg: #bbb;
    --pencil: #838383;
    --small-dig-bg: #dfd;
    --forbid-bg: #fee9e9;
    --same-bg: #fbb;
    --active-bg: rgba(10, 133, 255, 0.14);
    --overlay: rgba(0, 0, 0, 0.5);

    --page-width: 560px;
    --side: 8px; /* minimum margin at the sides of the game page */
    --cell: min(calc((100vw - 2 * var(--side)) / 9), 44px);
    --digit-size: calc(var(--cell) * 0.7); /* grid digits and digit buttons */
    --btn: min(10.5vw, 46px);
    --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

/* Native controls (dropdowns, scrollbars) follow a forced theme */
:root[data-theme="light"] {
    color-scheme: light;
}

:root[data-theme="dark"] {
    color-scheme: dark;
}

/* Dark theme: automatic (system setting) unless the user picked a theme in the
   settings (data-theme on <html>, see src/settings.ts). */
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --bg: #16181d;
        --fg: #e8e8ea;
        --grid-line: #e8e8ea;
        --grid-line-thin: #5a5d66;
        --disabled: #5f636c;
        --accent: #4aa3ff;
        --danger: #ff5a5a;
        --hyp: #2fd47a;
        --wrong: #ff5a5a;
        --selected-bg: #4a4e58;
        --pencil: #7b7e87;
        --small-dig-bg: #1e3a28;
        --forbid-bg: #2a2125;
        --same-bg: #6b2f33;
        --active-bg: rgba(74, 163, 255, 0.22);
        --overlay: rgba(0, 0, 0, 0.7);
    }
}

:root[data-theme="dark"] {
    --bg: #16181d;
    --fg: #e8e8ea;
    --grid-line: #e8e8ea;
    --grid-line-thin: #5a5d66;
    --disabled: #5f636c;
    --accent: #4aa3ff;
    --danger: #ff5a5a;
    --hyp: #2fd47a;
    --wrong: #ff5a5a;
    --selected-bg: #4a4e58;
    --pencil: #7b7e87;
    --small-dig-bg: #1e3a28;
    --forbid-bg: #2a2125;
    --same-bg: #6b2f33;
    --active-bg: rgba(74, 163, 255, 0.22);
    --overlay: rgba(0, 0, 0, 0.7);
}

html,
body {
    background: var(--bg);
    color: var(--fg);
    /* No pull-to-refresh / overscroll glow (the page is installable as an app) */
    overscroll-behavior: none;
}

body,
button,
input,
dialog {
    font-family: var(--font);
}

body {
    margin: 0;
}

[hidden] {
    display: none !important;
}

/* Bootstrap-like container: content (and the header buttons) stay in a
   centered column on wide screens and only touch the edges on narrow ones. */
[data-page] {
    padding: 0 16px 1em;
    max-width: var(--page-width);
    margin: 0 auto;
}

/* Dialogs share the page background. */
dialog {
    box-sizing: border-box;
    background: var(--bg);
    color: var(--fg);
    border: 1px solid var(--grid-line-thin);
    border-radius: 12px;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.35);
    padding: 0.8em 1.5em 1em;
    max-width: min(92vw, 520px);
    max-height: 90vh;
    overflow-y: auto;
    text-align: center;
}

dialog:focus,
dialog:focus-visible {
    outline: none;
}

dialog > :first-child {
    margin-top: 0;
}

dialog::backdrop {
    background: var(--overlay);
}

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

/* Everything clickable gets the same cursor. */
.gridCell,
.digit,
li,
.tool-item {
    cursor: pointer;
}

body {
    text-align: center;
}


.panel {
    margin: 0;
    padding: 0;
    font-size: 0;
}

.icon {
    width: 1em;
    height: 1em;
    fill: currentColor;
    display: block;
    margin-left: auto;
    margin-right: auto;
}

/* Title sits midway between the page top and the grid. */
h1 {
    text-align: center;
    margin: 0;
    padding: 0.75em 0 0.7em;
    line-height: 1.2;
}

/* The game uses (almost) the full width on phones */
[data-page="game"] {
    padding-left: var(--side);
    padding-right: var(--side);
}

/* Page header: back button | title | menu button */
.bar {
    position: relative;
    max-width: var(--page-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: 56px 1fr 56px;
    align-items: center;
}

.bar h1 {
    grid-column: 2;
}

.icon-btn {
    border: none;
    background: none;
    color: var(--fg);
    font-size: 28px;
    padding: 8px;
    cursor: pointer;
    justify-self: center;
}

#back-btn {
    grid-column: 1;
    grid-row: 1;
}

#menu-btn {
    grid-column: 3;
    grid-row: 1;
}

#menu {
    position: absolute;
    top: 100%;
    right: 12px;
    z-index: 5;
    min-width: 180px;
    background: var(--bg);
    border: 1px solid var(--grid-line-thin);
    border-radius: 12px;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.35);
    padding: 6px 0;
    text-align: left;
}

#menu a,
#menu span {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 18px;
    font-size: 18px;
    color: var(--fg);
    text-decoration: none;
    cursor: pointer;
}

#menu .icon {
    margin: 0;
    font-size: 22px;
    flex: none;
}

/* Settings */
.setting {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 14px 4px;
    font-size: 18px;
    border-bottom: 1px solid var(--grid-line-thin);
}

.setting select option {
    background: var(--bg);
    color: var(--fg);
}

.setting select {
    font: inherit;
    color: var(--fg);
    background: var(--bg);
    border: 2px solid var(--grid-line);
    border-radius: 8px;
    padding: 6px 10px;
}

#help,
#history,
#settings {
    text-align: left;
}

#history > p,
#history-content > p {
    font-weight: bold;
    font-size: 16px;
    margin: 18px 0 8px;
}

#history-empty {
    font-weight: normal !important;
}

.stats {
    display: table;
    width: 100%;
    border-collapse: collapse;
    font-size: 15px;
}

.stats th,
.stats td {
    text-align: left;
    padding: 6px 4px;
    border-bottom: 1px solid var(--grid-line-thin);
}

.stats th {
    font-weight: 600;
}

.stats .num {
    text-align: right;
    font-variant-numeric: tabular-nums;
}

#help > p {
    font-weight: bold;
    font-size: 16px;
    margin: 18px 0 8px;
}

table {
    display: inline-block;
    font-size: 14px;
}

#grid {
    table-layout: fixed;
    margin-top: 0px;
    border-collapse: collapse;
    border-spacing: 0;
}

/* The 3x3 pencil marks of a cell: a grid with equal tracks, so a mark is at the
   same place whichever other marks are present (table layout distributed the
   space by content). */
.innerTable {
    width: 100%;
    height: 100%;
    margin: 0;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    grid-template-rows: repeat(3, minmax(0, 1fr));
}

.innerTable tbody,
.innerTable tr {
    display: contents;
}

.gridRow {
    margin: 0;
    padding: 0;
}

.gridCell {
    width: var(--cell);
    height: var(--cell);
    text-align: center;
    font-weight: 600;
    font-size: var(--digit-size);
    line-height: 1;
    box-sizing: border-box;
    overflow: hidden;
    border: 1px dotted var(--grid-line-thin);
    margin: 0;
    padding: 0;
}

.subGridCell {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 0;
    color: var(--pencil);
    padding: 0;
    box-sizing: border-box;
    font-weight: 600;
    font-size: calc(var(--cell) * 0.3);
    line-height: 1;
    margin: 0;
}

/* Uniform button states: toggles are .active while on, any button can be
   .disabled. */
.active {
    color: var(--accent);
    background: var(--active-bg);
}

.digit.active {
    border-color: var(--accent);
}

.disabled {
    color: var(--disabled);
    background: none;
    cursor: default;
}

.digit.disabled {
    border-color: var(--disabled);
}

.topBorder {
    border-top: 2px solid var(--grid-line);
}

.bottomBorder {
    border-bottom: 2px solid var(--grid-line);
}

.leftBorder {
    border-left: 2px solid var(--grid-line);
}

.rightBorder {
    border-right: 2px solid var(--grid-line);
}

#digits {
    margin: 18px 0 10px 4px;
    border-spacing: 8px;
}

/* The click target of a button reaches into the gap to its neighbours (half the
   border-spacing of #digits), so clicking between the buttons hits one of them. */
.digit {
    position: relative;
    width: var(--btn);
    height: var(--btn);
    text-align: center;
    /* same digit style as the grid cells; same outline as the block borders */
    font-size: var(--digit-size);
    font-weight: 600;
    border: 2px solid var(--grid-line);
    border-radius: 8px;
    padding: 0px;
    margin: 0;
}

.digit::after {
    content: "";
    position: absolute;
    /* measured from inside the 2px border: 4px beyond the border box */
    inset: -6px;
}


ul {
    margin: 0px auto;
    padding-left: 5px;
    max-width: 700px;
    list-style: none;
    text-align: left;
    font-size: 1px;
    display: inline-block;
}

li {
    position: relative;
    z-index: 0;
    display: inline-block;
    padding: 0 8px;
    width: 42px;
    list-style: none;
    text-align: center;
    font-weight: normal;
    font-size: 32px;
}

#buttons2 {
    display: flex;
    justify-content: center;
    gap: 0;
    padding: 0;
    max-width: 100%;
}

#buttons2 li {
    width: calc(var(--btn) * 1.05);
    padding: 4px 0;
    border-radius: 10px;
    font-size: calc(var(--btn) * 0.75);
}

#newGrid ul {
    margin: 0 auto;
}

#newGrid li {
    display: table;
    margin: 0 auto;
    text-align: center;
    color: var(--accent);
    font-size: 18px;
    padding-bottom: 6px;
    width: 200px;
}

#confirm p {
    max-width: 260px;
    margin: 0 auto 1em;
}

#restart li,
#confirm li,
#tools li {
    font-size: 24px;
    width: auto;
}

/* Icon legend of the help page: icon column + text column */
#help ul {
    display: grid;
    grid-template-columns: 48px 1fr;
    align-items: center;
    row-gap: 10px;
    width: 100%;
    max-width: none;
    margin: 0;
    padding: 0;
    font-size: 16px;
}

#help li {
    display: block;
    width: auto;
    padding: 0;
    font-size: 28px;
    cursor: default;
}

#help > p,
#keyboard-help > p {
    font-weight: bold;
    font-size: 16px;
    margin: 18px 0 8px;
}

#help > p.help-text {
    font-weight: normal;
    font-size: 15px;
    line-height: 1.45;
    margin: 0 0 10px;
}

#help li.help {
    font-size: 15px;
    text-align: left;
}

/* Dialog sizes */
#win {
    width: min(460px, 92vw);
}

video {
    display: block;
    margin-left: auto;
    margin-right: auto;
    width: 90%;
}

/* Tools dialog */
.tool-item {
    display: block;
    width: 100%;
    font: inherit;
    font-size: 18px;
    color: var(--accent);
    background: none;
    border: none;
    padding: 10px 0;
    cursor: pointer;
}

.tool-item:focus,
.tool-item:focus-visible {
    outline: none;
}

.tool-item.disabled {
    color: var(--disabled);
}

#tools-note {
    margin: 4px 0 8px;
}

/* Keyboard shortcuts in the help (shown by src/pages.ts when a keyboard is likely) */

.shortcuts {
    display: grid;
    grid-template-columns: max-content 1fr;
    gap: 8px 16px;
    margin: 0;
    font-size: 15px;
    align-items: center;
}

.shortcuts dt,
.shortcuts dd {
    margin: 0;
}

kbd {
    display: inline-block;
    min-width: 1.6em;
    padding: 2px 6px;
    font: inherit;
    font-size: 13px;
    text-align: center;
    border: 1px solid var(--grid-line-thin);
    border-bottom-width: 2px;
    border-radius: 6px;
}

/* Solving time below the buttons (empty when no clock is running) */
.timer {
    min-height: 1.4em;
    margin: 14px 0 0;
    font-size: 18px;
    font-variant-numeric: tabular-nums;
    color: var(--disabled);
}