:root {
    --bg-gradient: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    --card-bg: rgba(255, 255, 255, 0.08);
    --card-border: rgba(255, 255, 255, 0.15);
    --match-wood: linear-gradient(180deg, #f5d17a 0%, #d97706 50%, #a55a10 100%);
    --match-head: radial-gradient(circle at 30% 30%, #ff6b6b, #b91c1c);
    --slot-empty: rgba(255, 255, 255, 0.08);
    --slot-hover: rgba(255, 255, 255, 0.15);
    --primary: #6366f1;
    --primary-glow: rgba(99, 102, 241, 0.4);
    --success: #10b981;
    --accent: #f59e0b;
    --text: #f1f5f9;
    --text-muted: #94a3b8;
}

* { 
    box-sizing: border-box; 
    touch-action: none; 
    user-select: none; 
    -webkit-user-select: none;
    -webkit-touch-callout: none;
    -webkit-user-drag: none;
    -webkit-tap-highlight-color: transparent; 
}

body { 
    margin: 0; 
    font-family: 'Segoe UI', -apple-system, system-ui, sans-serif; 
    background: var(--bg-gradient);
    color: var(--text);
    min-height: 100vh;
    overflow-x: hidden;
}

html,
body {
    width: 100%;
    height: 100%;
    overflow: hidden;
    overscroll-behavior: none;
}

#app { 
    width: 100%; 
    max-width: 900px; 
    height: var(--app-height, 100dvh);
    min-height: var(--app-height, 100dvh);
    margin: 0 auto;
    position: relative; 
    padding: 20px;
    padding-top: calc(env(safe-area-inset-top, 0px) + 20px);
    overflow: hidden;
}

#app.boot-hidden {
    visibility: hidden;
}

.boot-loader {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(145deg, #141c36 0%, #0f264f 100%);
    z-index: 3000;
    transition: opacity 0.35s ease;
}

.boot-loader.hidden {
    opacity: 0;
    pointer-events: none;
}

.boot-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 14px;
    padding: 24px 28px;
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    background: rgba(255, 255, 255, 0.06);
    box-shadow: 0 20px 45px rgba(0, 0, 0, 0.4);
    color: var(--text);
    font-weight: 600;
}

.boot-spinner {
    width: 42px;
    height: 42px;
    border-radius: 50%;
    border: 3px solid rgba(255, 255, 255, 0.2);
    border-top-color: var(--primary);
    animation: spin 0.9s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Screens */
.screen { 
    position: absolute; 
    inset: 0; 
    display: none; 
    flex-direction: column; 
    align-items: center; 
    justify-content: center; 
    padding: 30px;
    animation: fadeIn 0.4s ease-out;
    overflow: hidden;
}
.screen.active { display: flex; }

#start-content {
    width: 100%;
    max-width: 620px;
    display: flex;
    flex-direction: column;
    align-items: center;
    transform-origin: top center;
}

#screen-game {
    justify-content: flex-start;
    padding-top: calc(env(safe-area-inset-top, 0px) + 64px);
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Title */
#game-title {
    font-size: clamp(28px, 6vw, 48px);
    font-weight: 800;
    background: linear-gradient(135deg, #fff 0%, #a5b4fc 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-align: center;
    margin-bottom: 40px;
    text-shadow: 0 4px 30px rgba(99, 102, 241, 0.3);
}

/* ===== 7-SEGMENT DISPLAY ===== */
#match-field { 
    display: flex; 
    flex-wrap: wrap; 
    justify-content: center; 
    align-items: center; 
    padding: 40px 30px;
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    border-radius: 24px; 
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.4);
    margin: 20px 0;
    gap: 15px;
}

/* Token container for digit or operator */
.token {
    position: relative;
}

/* ===== DIGIT: 7-segment display ===== */
.digit {
    width: 52px;
    height: 90px;
    position: relative;
}

/* Individual segment slot */
.segment {
    position: absolute;
    border-radius: 3px;
    cursor: pointer;
    transition: all 0.15s ease;
}

/* Horizontal segments - thinner and wider */
.segment.h {
    width: 32px;
    height: 8px;
}

/* Vertical segments - taller and thinner */
.segment.v {
    width: 8px;
    height: 32px;
}

/* ===== SEGMENT POSITIONS ===== */
/* a - top horizontal */
.segment.seg-a { 
    top: 0; 
    left: 10px; 
}

/* b - top right vertical */
.segment.seg-b { 
    top: 10px; 
    left: 44px; 
}

/* c - bottom right vertical */
.segment.seg-c { 
    top: 48px; 
    left: 44px; 
}

/* d - bottom horizontal */
.segment.seg-d { 
    top: 82px; 
    left: 10px; 
}

/* e - bottom left vertical */
.segment.seg-e { 
    top: 48px; 
    left: 0; 
}

/* f - top left vertical */
.segment.seg-f { 
    top: 10px; 
    left: 0; 
}

/* g - middle horizontal */
.segment.seg-g { 
    top: 41px; 
    left: 10px; 
}

/* Empty slot style */
.segment.empty {
    background: var(--slot-empty);
    border: 1px dashed rgba(255,255,255,0.15);
}
.segment.empty:hover {
    background: var(--slot-hover);
    border-color: var(--primary);
}

/* Active match (with matchstick) */
.segment.active {
    background: var(--match-wood);
    border: none;
    box-shadow: 0 2px 8px rgba(217, 119, 6, 0.5), inset 0 1px 0 rgba(255,255,255,0.3);
}

/* Match head */
.segment.active::before {
    content: '';
    position: absolute;
    width: 11px;
    height: 11px;
    background: var(--match-head);
    border-radius: 50%;
    box-shadow: 0 0 6px rgba(185, 28, 28, 0.5);
}

.segment.h.active::before {
    right: -5px;
    top: 50%;
    transform: translateY(-50%);
}

.segment.v.active::before {
    bottom: -5px;
    left: 50%;
    transform: translateX(-50%);
}

/* ===== OPERATOR TOKENS ===== */
.operator {
    width: 44px;
    height: 90px;
    position: relative;
}

.op-slot {
    position: absolute;
    border-radius: 3px;
    cursor: pointer;
    transition: all 0.15s ease;
}

.op-slot.h {
    width: 32px;
    height: 8px;
    top: 41px;
    left: 6px;
}

.op-slot.v {
    width: 8px;
    height: 32px;
    top: 29px;
    left: 18px;
}

.op-slot.empty {
    background: var(--slot-empty);
    border: 1px dashed rgba(255,255,255,0.15);
}

.op-slot.active {
    background: var(--match-wood);
    box-shadow: 0 2px 8px rgba(217, 119, 6, 0.5);
}

.op-slot.active::before {
    content: '';
    position: absolute;
    width: 11px;
    height: 11px;
    background: var(--match-head);
    border-radius: 50%;
}

.op-slot.h.active::before {
    right: -5px;
    top: -1px;
}

.op-slot.v.active::before {
    bottom: -5px;
    left: -1px;
}

/* Equals sign (fixed, non-interactive) */
.equals {
    width: 44px;
    height: 90px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 14px;
}

.eq-bar {
    width: 32px;
    height: 8px;
    background: var(--match-wood);
    border-radius: 3px;
    box-shadow: 0 2px 8px rgba(217, 119, 6, 0.5);
}

/* ===== BUTTONS ===== */
.menu-buttons {
    display: flex;
    flex-direction: column;
    gap: 16px;
    width: 100%;
    max-width: 280px;
}

.overall-top {
    margin-top: 24px;
    width: 100%;
    max-width: 360px;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 16px 18px;
}

.overall-top-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 8px;
}

#overall-top-list {
    margin: 0;
    padding-left: 20px;
    color: var(--text-muted);
    display: flex;
    flex-direction: column;
    gap: 6px;
    font-size: 15px;
}

.overall-my-rank {
    margin-top: 10px;
    padding-top: 10px;
    border-top: 1px solid rgba(255, 255, 255, 0.14);
    color: var(--text);
    font-size: 14px;
    font-weight: 600;
}

button { 
    padding: 16px 32px; 
    border: none; 
    border-radius: 16px; 
    font-size: 18px; 
    font-weight: 600;
    cursor: pointer; 
    transition: all 0.2s ease;
    position: relative;
    overflow: hidden;
}

button::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(rgba(255,255,255,0.1), transparent);
    pointer-events: none;
}

button:hover { 
    transform: translateY(-2px);
}

button:active { 
    transform: scale(0.98) translateY(0);
}

button.primary { 
    background: linear-gradient(135deg, #6366f1 0%, #4f46e5 100%);
    color: white; 
    box-shadow: 0 8px 20px var(--primary-glow);
}

button.primary:hover {
    box-shadow: 0 12px 28px var(--primary-glow);
}

button.secondary { 
    background: rgba(255,255,255,0.1);
    color: var(--text);
    border: 1px solid var(--card-border);
}

button.icon-btn { 
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    color: var(--text);
    padding: 12px 20px;
    font-size: 16px;
}

button.text-btn { 
    background: transparent; 
    color: var(--text-muted);
    font-size: 16px;
    padding: 10px 20px;
}

.home-btn {
    position: absolute;
    top: calc(env(safe-area-inset-top, 0px) + 12px);
    right: calc(env(safe-area-inset-right, 0px) + 12px);
    width: 44px;
    height: 44px;
    padding: 0;
    margin: 0;
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.24);
    backdrop-filter: blur(10px);
    color: var(--text);
    font-size: 24px;
    line-height: 1;
    border-radius: 12px;
    z-index: 1500;
}

button.reward-btn { 
    background: linear-gradient(135deg, #8b5cf6 0%, #7c3aed 100%);
    color: white;
    box-shadow: 0 8px 20px rgba(139, 92, 246, 0.3);
}

.hidden { display: none !important; }

/* ===== HEADER ===== */
header { 
    width: 100%; 
    display: flex; 
    justify-content: space-between; 
    align-items: flex-start; 
    margin-bottom: 20px;
    padding: 20px;
    padding-right: 72px;
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border-radius: 16px;
    border: 1px solid var(--card-border);
}

.stats { 
    display: flex; 
    flex-direction: column; 
    gap: 4px; 
}

#label-puzzle-index { 
    font-weight: 700; 
    font-size: 22px; 
    color: var(--text);
}

#game-timer { 
    font-family: 'Courier New', monospace;
    font-size: 28px; 
    color: var(--accent);
    font-weight: 700;
}

.leader-info { 
    text-align: right; 
    font-size: 14px; 
    color: var(--text-muted);
}

.leader-info div {
    margin-bottom: 4px;
}

#instruction {
    font-size: 20px;
    color: var(--text);
    font-weight: 500;
    text-align: center;
    padding: 16px 24px;
    background: var(--card-bg);
    border-radius: 12px;
    border: 1px solid var(--card-border);
    margin-bottom: 10px;
}

/* ===== GAME CONTROLS ===== */
.game-controls {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    justify-content: center;
    margin-top: 10px;
}

/* ===== DRAG GHOST ===== */
#drag-ghost { 
    pointer-events: none; 
    position: fixed; 
    z-index: 1000; 
    opacity: 0.95;
    border-radius: 3px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    display: none;
}

#drag-ghost.v {
    width: 8px;
    height: 32px;
    background: var(--match-wood);
}

#drag-ghost.h {
    width: 32px;
    height: 8px;
    background: var(--match-wood);
}

#drag-ghost::before {
    content: '';
    position: absolute;
    width: 11px;
    height: 11px;
    background: var(--match-head);
    border-radius: 50%;
}

#drag-ghost.v::before {
    bottom: -5px;
    left: -1px;
}

#drag-ghost.h::before {
    right: -5px;
    top: -1px;
}

/* ===== RESULT SCREEN ===== */
.result-stats { 
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    padding: 30px; 
    border-radius: 20px; 
    margin: 30px 0; 
    width: 100%; 
    max-width: 320px;
}

.result-stats p { 
    display: flex; 
    justify-content: space-between; 
    margin: 12px 0; 
    font-size: 18px;
    color: var(--text-muted);
}

.result-stats span { 
    font-weight: bold; 
    color: var(--accent);
}

#msg-success {
    font-size: 42px;
    font-weight: 800;
    background: linear-gradient(135deg, #10b981 0%, #34d399 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Settings */
.settings {
    position: absolute;
    top: 20px;
    right: 20px;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 600px) {
    #start-content {
        max-width: 360px;
    }

    #screen-game {
        padding-top: calc(env(safe-area-inset-top, 0px) + 56px);
    }

    .game-controls {
        width: 100%;
        max-width: 340px;
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 10px;
        margin-top: 4px;
    }

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

    #btn-reset {
        grid-column: 2;
        grid-row: 1;
    }

    #btn-hint {
        grid-column: 1 / -1;
        grid-row: 2;
        width: 100%;
        min-width: 0;
        font-size: 14px;
        padding: 12px 10px;
        line-height: 1.2;
    }

    #match-field { 
        padding: 30px 10px;
        gap: 6px;
    }
    
    /* ... (digits code remains same, skipping for brevity in this tool call, but I will apply changes to result screen below) ... */
    
    /* Compact Result Screen for Mobile */
    #msg-success { font-size: 32px; margin: 10px 0; }
    .result-stats { padding: 20px; margin: 15px 0; }
    .result-stats p { font-size: 16px; margin: 8px 0; }
    
    button {
        padding: 14px 24px;
        font-size: 16px;
    }

    .home-btn {
        width: 40px;
        height: 40px;
        font-size: 22px;
        top: calc(env(safe-area-inset-top, 0px) + 10px);
        right: calc(env(safe-area-inset-right, 0px) + 10px);
    }
    
    #label-puzzle-index { font-size: 20px; }
    #game-timer { font-size: 26px; }

    .overall-top {
        max-width: 320px;
        margin-top: 18px;
    }
    
    /* Ensure drag ghost matches new size */
    #drag-ghost.v { width: 10px; height: 45px; }
    #drag-ghost.h { width: 42px; height: 10px; }
    #drag-ghost::before { width: 14px; height: 14px; }
}

@media (max-width: 600px) and (orientation: portrait) and (max-height: 760px) {
    header {
        margin-bottom: 12px;
    }

    #instruction {
        margin-bottom: 6px;
        padding: 12px 18px;
        font-size: 18px;
    }

    #match-field {
        padding: 20px 8px;
        margin-bottom: 2px;
    }

    .game-controls {
        margin-top: 0;
        gap: 8px;
    }

    #btn-hint {
        font-size: 13px;
        padding: 10px 8px;
    }
}

/* Landscape Mode Fixes */
@media (max-height: 600px) and (orientation: landscape) {
    #app { 
        padding: 5px; 
        height: var(--app-height, 100vh);
        display: flex;
        align-items: center;
        justify-content: center;
    }

    #screen-start.active {
        justify-content: flex-start;
        padding-top: calc(env(safe-area-inset-top, 0px) + 18px);
        padding-bottom: calc(env(safe-area-inset-bottom, 0px) + 10px);
    }

    #game-title {
        font-size: clamp(24px, 5vh, 52px);
        margin-bottom: 14px;
    }

    .menu-buttons {
        gap: 10px;
    }

    .overall-top {
        margin-top: 12px;
        padding: 12px 14px;
    }
    
    .screen {
        overflow: hidden;
        justify-content: center;
    }

    #screen-game.active {
        display: grid;
        grid-template-columns: auto 1fr;
        grid-template-rows: auto auto;
        column-gap: 20px;
        row-gap: 5px;
        width: 100%;
        height: 100%;
        padding: 5px;
        justify-items: center;
        align-content: center;
        overflow: hidden; /* Game screen shouldn't scroll usually */
    }
    
    /* Compact Result Screen for Landscape */
    #screen-success.active {
        flex-direction: row; /* Side by side layout for landscape results */
        gap: 30px;
    }
    
    #msg-success {
        font-size: 36px;
        margin: 0;
        text-align: right;
    }
    
    .result-stats {
        margin: 0;
        padding: 20px;
        width: auto;
        min-width: 250px;
    }

    header {
        grid-area: 1 / 1 / 3 / 2;
        flex-direction: column;
        justify-content: center;
        height: auto;
        margin: 0;
        padding: 15px;
        gap: 15px;
        width: 160px;
        padding-right: 15px; 
    }
/* ... rest of landscape styles ... */
    
    /* Digit container (1.5x larger: 44x80 -> 66x120) */
    .digit {
        width: 66px;
        height: 120px;
    }
    
    /* Segments (1.5x) */
    .segment.h {
        width: 42px;
        height: 10px;
    }
    
    .segment.v {
        width: 10px;
        height: 45px;
    }
    
    /* Positions updated for 66x120 size */
    .segment.seg-a { top: 0; left: 12px; }
    .segment.seg-b { top: 12px; left: 56px; }
    .segment.seg-c { top: 67px; left: 56px; }
    .segment.seg-d { top: 110px; left: 12px; }
    .segment.seg-e { top: 67px; left: 0; }
    .segment.seg-f { top: 12px; left: 0; }
    .segment.seg-g { top: 55px; left: 12px; }
    
    .segment.active::before {
        width: 14px;
        height: 14px;
    }
    
    /* Operator */
    .operator {
        width: 50px;
        height: 120px;
    }
    
    .op-slot.h { width: 42px; height: 10px; top: 55px; left: 4px; }
    .op-slot.v { width: 10px; height: 45px; top: 38px; left: 20px; }
    
    .op-slot.active::before {
        width: 14px;
        height: 14px;
    }

    /* Equals */
    .equals { width: 50px; height: 120px; gap: 18px; }
    .eq-bar { width: 42px; height: 10px; }
    
    button {
        padding: 14px 24px;
        font-size: 16px;
    }
    
    #label-puzzle-index { font-size: 20px; }
    #game-timer { font-size: 26px; }
    
    /* Ensure drag ghost matches new size */
    #drag-ghost.v { width: 10px; height: 45px; }
    #drag-ghost.h { width: 42px; height: 10px; }
    #drag-ghost::before { width: 14px; height: 14px; }
}

/* Landscape Mode Fixes */
@media (max-height: 600px) and (orientation: landscape) {
    #app { 
        padding: 5px; 
        height: var(--app-height, 100vh);
        display: flex;
        align-items: center;
        justify-content: center;
    }

    #screen-game.active {
        display: grid;
        grid-template-columns: auto 1fr;
        grid-template-rows: auto auto;
        column-gap: 20px;
        row-gap: 5px;
        width: 100%;
        height: 100%;
        padding: 5px;
        justify-items: center;
        align-content: center;
    }

    header {
        grid-area: 1 / 1 / 3 / 2;
        flex-direction: column;
        justify-content: center;
        height: auto;
        margin: 0;
        padding: 15px;
        gap: 15px;
        width: 160px;
        /* Reset padding for desktop landscape logic */
        padding-right: 15px; 
    }

    #instruction {
        grid-area: 1 / 2 / 2 / 3;
        margin: 0;
        padding: 8px 20px;
        font-size: 16px;
    }

    #match-field {
        grid-area: 2 / 2 / 3 / 3;
        margin: 0;
        padding: 15px;
        /* Transform managed by JS fitToScreen */
        transform-origin: center center;
    }

    .game-controls {
        grid-area: 3 / 1 / 4 / 3;
        margin: 5px 0 0 0;
    }

    .game-controls button {
        padding: 8px 16px;
        font-size: 14px;
    }

    .home-btn {
        width: 36px;
        height: 36px;
        font-size: 20px;
        top: calc(env(safe-area-inset-top, 0px) + 8px);
        right: calc(env(safe-area-inset-right, 0px) + 8px);
    }
    
    .leader-info { font-size: 12px; }
    #game-timer { font-size: 20px; }
}

/* Highlight for valid drop targets */
.segment.highlight, .op-slot.highlight {
    background: rgba(99, 102, 241, 0.3) !important;
    border: 2px dashed var(--primary) !important;
    animation: pulse 1s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}

/* ===== MODAL ===== */
.modal {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(5px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    animation: fadeIn 0.2s ease-out;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: linear-gradient(145deg, #1e293b, #0f172a);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    padding: 40px;
    text-align: center;
    max-width: 360px;
    width: 90%;
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.5);
    animation: modalPop 0.3s ease-out;
}

@keyframes modalPop {
    from { transform: scale(0.8); opacity: 0; }
    to { transform: scale(1); opacity: 1; }
}

#modal-icon {
    font-size: 64px;
    margin-bottom: 20px;
}

#modal-text {
    font-size: 20px;
    color: var(--text);
    margin-bottom: 30px;
    line-height: 1.5;
}

.modal-content button {
    min-width: 140px;
}