/* ============================================================
   Shmiloku - Mobile-First Puzzle Game
   ============================================================ */

:root {
    --bg: #faf8f5;
    --bg-card: #ffffff;
    --text: #2c2c2c;
    --text-secondary: #7a7a7a;
    --accent: #3a7bd5;
    --accent-light: #eaf2fb;
    --error: #d94f4f;
    --success: #4caf7d;
    --given-text: #444;
    --selected-bg: rgba(58, 123, 213, 0.18);
    --selected-text: #2c2c2c;
    --selected-border: #3a7bd5;
    --highlight-bg: rgba(58, 123, 213, 0.07);
    --same-number-bg: rgba(58, 123, 213, 0.12);
    --border: #e0ddd8;
    --region-border: #444;
    --cell-border: #ccc8c0;
    --shadow: 0 2px 8px rgba(0,0,0,0.06);
    --shadow-lg: 0 4px 12px rgba(0,0,0,0.08);
    --radius: 12px;
    --radius-sm: 8px;
    --region-0: #fef3dc; --region-1: #e8f0f2; --region-2: #fde4dd;
    --region-3: #ddf2ef; --region-4: #e9e4f5; --region-5: #f5ecd7;
    --region-6: #ddf0e2; --region-7: #f5dde8; --region-8: #dde8f5;
    --region-9: #f5e0d0; --region-10: #d8f0ed; --region-11: #e6ddf5;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: #121218; --bg-card: #1c1c26; --text: #e0ddd8;
        --text-secondary: #888; --accent: #6a9fdf; --accent-light: #1e2838;
        --given-text: #aaa;
        --selected-bg: rgba(106,159,223,0.2); --selected-text: #e0ddd8;
        --selected-border: #6a9fdf;
        --highlight-bg: rgba(106,159,223,0.08);
        --same-number-bg: rgba(106,159,223,0.14);
        --border: #2a2a36; --region-border: #777; --cell-border: #333;
        --shadow: 0 2px 8px rgba(0,0,0,0.3);
        --region-0: #2a2518; --region-1: #1c2528; --region-2: #2a1e1c;
        --region-3: #1a2826; --region-4: #221e2c; --region-5: #28241a;
        --region-6: #1a2820; --region-7: #2a1c22; --region-8: #1a2230;
        --region-9: #2a2018; --region-10: #182826; --region-11: #221a2c;
    }
}

/* === Reset === */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html { height: 100%; width: 100%; overflow: hidden; }
body { height: 100%; width: 100%; position: fixed; top: 0; left: 0; overscroll-behavior: none; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; background: var(--bg); color: var(--text); user-select: none; -webkit-user-select: none; }
select, input { user-select: auto; -webkit-user-select: auto; }

/* === Screens === */
.screen { display: none; flex-direction: column; position: fixed; top: 0; left: 0; right: 0; bottom: 0; width: 100%; height: 100%; height: 100dvh; overflow-x: hidden; overflow-y: hidden; z-index: 1; background: var(--bg); }
.screen.active { display: flex; }
.screen.scrollable { overflow-y: auto !important; -webkit-overflow-scrolling: touch; overscroll-behavior-y: contain; touch-action: pan-y; }
.screen.no-scroll { overflow: hidden !important; touch-action: none; }

/* === Header === */
.header { display: flex; align-items: center; justify-content: space-between; padding: 8px 16px; background: var(--bg-card); border-bottom: 1px solid var(--border); min-height: 44px; flex-shrink: 0; }
.header-title { font-size: 18px; font-weight: 800; color: var(--accent); }
.header-info { font-size: 13px; color: var(--text-secondary); }
.timer { font-variant-numeric: tabular-nums; font-weight: 600; min-width: 48px; font-size: 14px; color: var(--text-secondary); }
.btn-icon { background: none; border: none; color: var(--text-secondary); font-size: 20px; cursor: pointer; padding: 8px; border-radius: 4px; }

/* === Menu === */
.menu-screen { justify-content: center; align-items: center; gap: 24px; padding: 24px; }
.menu-title { font-size: 48px; font-weight: 900; color: var(--accent); letter-spacing: -2px; }
.menu-subtitle { font-size: 14px; color: var(--text-secondary); margin-top: -16px; }
.menu-options { display: flex; flex-direction: column; gap: 12px; width: 100%; max-width: 320px; }
.menu-btn { padding: 16px 24px; border: 2px solid var(--border); border-radius: var(--radius); background: var(--bg-card); color: var(--text); font-size: 16px; font-weight: 600; cursor: pointer; text-align: center; box-shadow: var(--shadow); }
.menu-btn:active { transform: scale(0.97); border-color: var(--accent); background: var(--accent-light); }

/* === Level Select === */
.size-tabs { display: flex; gap: 8px; padding: 12px 16px 8px; flex-shrink: 0; overflow-x: auto; touch-action: pan-x; -webkit-overflow-scrolling: touch; }
.size-tab { padding: 8px 16px; border: 2px solid var(--border); border-radius: 20px; background: var(--bg); color: var(--text); font-weight: 600; font-size: 14px; cursor: pointer; white-space: nowrap; flex-shrink: 0; }
.size-tab.active { background: var(--accent); color: white; border-color: var(--accent); }
.level-select { padding: 16px; padding-bottom: max(24px, env(safe-area-inset-bottom)); }
.diff-section { margin-bottom: 20px; }
.diff-section h3 { font-size: 14px; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 8px; }
.level-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(48px, 1fr)); gap: 6px; }
.level-item { aspect-ratio: 1; border: 2px solid var(--border); border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 14px; cursor: pointer; background: var(--bg-card); }
.level-item:active { transform: scale(0.92); }
.level-item.completed { background: var(--success); color: white; border-color: var(--success); }

/* === Game Grid === */
.grid-container { flex: 1; display: flex; align-items: center; justify-content: center; padding: 8px; min-height: 0; overflow: hidden; }
.grid { display: grid; gap: 0; border: 2.5px solid var(--region-border); border-radius: var(--radius-sm); overflow: hidden; box-shadow: var(--shadow-lg); --grid-max: min(88vw, calc(100dvh - 230px)); max-width: var(--grid-max); max-height: var(--grid-max); width: 100%; aspect-ratio: 1; }
.cell { display: flex; align-items: center; justify-content: center; font-size: clamp(16px, 5vw, 32px); font-weight: 600; cursor: pointer; position: relative; transition: background 0.1s; border: 0.5px solid var(--cell-border); }
.cell.given { font-weight: 700; color: var(--given-text); cursor: default; }
.cell.selected { background: var(--selected-bg) !important; color: var(--selected-text); z-index: 2; box-shadow: inset 0 0 0 2.5px var(--selected-border); }
.cell.same-number { background: var(--same-number-bg) !important; }
.cell.error { color: var(--error); animation: shake 0.3s ease-in-out; }
.cell.error::after { content: ''; position: absolute; inset: 2px; border: 2px solid var(--error); border-radius: 2px; pointer-events: none; }
.cell.border-top { border-top: 2.5px solid var(--region-border); }
.cell.border-bottom { border-bottom: 2.5px solid var(--region-border); }
.cell.border-left { border-left: 2.5px solid var(--region-border); }
.cell.border-right { border-right: 2.5px solid var(--region-border); }
.cell .notes { display: grid; grid-template-columns: repeat(3, 1fr); grid-template-rows: repeat(3, 1fr); width: 100%; height: 100%; font-size: clamp(7px, 2vw, 12px); font-weight: 400; color: var(--text-secondary); }
.cell .notes span { display: flex; align-items: center; justify-content: center; }

/* === Controls (numpad + actions) === */
.controls { padding: 8px; display: flex; flex-direction: column; gap: 6px; background: var(--bg-card); border-top: 1px solid var(--border); flex-shrink: 0; padding-bottom: max(8px, env(safe-area-inset-bottom)); }
.numpad { display: flex; gap: 4px; justify-content: center; }
.numpad-btn { flex: 1 1 0; min-width: 0; height: 44px; border: 2px solid var(--border); border-radius: var(--radius-sm); background: var(--bg); color: var(--text); font-size: clamp(15px, 4.5vw, 22px); font-weight: 700; cursor: pointer; display: flex; align-items: center; justify-content: center; }
.numpad-btn:active { transform: scale(0.92); background: var(--accent); color: white; border-color: var(--accent); }
.numpad-btn.active { background: var(--accent); color: white; border-color: var(--accent); }
.actions { display: flex; gap: 6px; justify-content: center; }
.action-btn { flex: 1; max-width: 100px; padding: 8px 4px; border: 1.5px solid var(--border); border-radius: var(--radius-sm); background: var(--bg); color: var(--text); font-size: 11px; font-weight: 600; cursor: pointer; display: flex; align-items: center; justify-content: center; gap: 3px; }
.action-btn:active { transform: scale(0.95); background: var(--accent-light); }
.action-btn.active { background: var(--accent); color: white; border-color: var(--accent); }
.action-btn .icon { font-size: 14px; }

/* === How to Play === */
.howto-content { padding: 16px; padding-bottom: max(24px, env(safe-area-inset-bottom)); max-width: 480px; margin: 0 auto; }
.rule-card { margin-bottom: 16px; padding: 16px; background: var(--bg-card); border-radius: 12px; border: 1px solid var(--border); }
.rule-card h3 { color: var(--accent); margin-bottom: 8px; font-size: 15px; }
.rule-card p, .rule-card li { color: var(--text-secondary); font-size: 14px; line-height: 1.5; }
.rule-card ul { padding-left: 20px; line-height: 1.8; }

/* === Settings === */
.settings-list { padding: 16px; padding-bottom: max(24px, env(safe-area-inset-bottom)); }
.setting-item { display: flex; justify-content: space-between; align-items: center; padding: 14px 0; border-bottom: 1px solid var(--border); gap: 12px; }
.setting-label { font-weight: 600; }
.setting-desc { font-size: 12px; color: var(--text-secondary); }
.toggle { width: 48px; height: 28px; border-radius: 14px; background: var(--border); position: relative; cursor: pointer; transition: background 0.2s; flex-shrink: 0; }
.toggle.on { background: var(--accent); }
.toggle::after { content: ''; position: absolute; width: 22px; height: 22px; border-radius: 50%; background: white; top: 3px; left: 3px; transition: transform 0.2s; }
.toggle.on::after { transform: translateX(20px); }
.lang-select { padding: 8px 12px; border: 2px solid var(--border); border-radius: var(--radius-sm); background: var(--bg); color: var(--text); font-size: 14px; font-weight: 600; cursor: pointer; -webkit-appearance: menulist; appearance: menulist; }

/* === Overlay === */
.overlay { display: none; position: fixed; inset: 0; background: rgba(0,0,0,0.5); z-index: 100; align-items: center; justify-content: center; padding: 24px; }
.overlay.active { display: flex; }
.overlay-card { background: var(--bg-card); border-radius: var(--radius); padding: 32px 24px; text-align: center; max-width: 320px; width: 100%; box-shadow: var(--shadow-lg); animation: pop 0.3s ease-out; }
.overlay-card h2 { font-size: 28px; margin-bottom: 8px; }
.overlay-card .stats { color: var(--text-secondary); font-size: 14px; margin-bottom: 20px; }
.overlay-card .btn-row { display: flex; gap: 8px; }
.overlay-card .btn-row button { flex: 1; padding: 12px; border: 2px solid var(--border); border-radius: var(--radius-sm); font-size: 14px; font-weight: 600; cursor: pointer; }
.overlay-card .btn-primary { background: var(--accent); color: white; border-color: var(--accent); }
.overlay-card .btn-secondary { background: var(--bg); color: var(--text); }

/* === Confetti === */
.confetti-piece { position: fixed; width: 10px; height: 10px; z-index: 200; pointer-events: none; }

/* === RTL === */
[dir="rtl"] .btn-back { transform: scaleX(-1); }
[dir="rtl"] .rule-card ul { padding-left: 0; padding-right: 20px; }

/* === Animations === */
@keyframes shake { 0%, 100% { transform: translateX(0); } 25% { transform: translateX(-3px); } 75% { transform: translateX(3px); } }
@keyframes pop { 0% { transform: scale(0.8); opacity: 0; } 50% { transform: scale(1.1); } 100% { transform: scale(1); opacity: 1; } }
.cell.just-placed { animation: pop 0.2s ease-out; }

/* === Responsive === */
@media (min-width: 600px) {
    .grid { max-width: 400px; max-height: 400px; }
    .numpad-btn { max-width: 52px; height: 48px; }
}
@media (max-height: 700px) {
    .header { padding: 4px 12px; min-height: 36px; }
    .grid { --grid-max: min(88vw, calc(100dvh - 200px)); }
    .controls { padding: 4px 6px; gap: 4px; padding-bottom: max(4px, env(safe-area-inset-bottom)); }
    .numpad-btn { height: 38px; }
    .action-btn { padding: 6px 3px; font-size: 10px; }
}
@media (max-height: 600px) {
    .grid { --grid-max: min(85vw, calc(100dvh - 180px)); }
    .numpad-btn { height: 34px; }
}
@media (max-height: 500px) and (orientation: landscape) {
    .header { padding: 2px 12px; min-height: 28px; }
    .grid { --grid-max: min(50vw, calc(100dvh - 140px)); }
    .controls { padding: 2px 6px; gap: 2px; }
    .numpad-btn { height: 28px; }
}