:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #64748b;
    --accent-color: #f59e0b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --water-color: #0ea5e9;
    --ship-color: #374151;
    --hit-color: #dc2626;
    --miss-color: #6b7280;
    --background: #f8fafc;
    --surface: #ffffff;
    --border: #e2e8f0;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, var(--water-color) 0%, var(--primary-color) 100%);
    min-height: 100vh;
    color: var(--text-primary);
}

.game-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--surface);
    padding: 1rem 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
}

header h1 {
    color: var(--primary-color);
    font-size: 2rem;
    font-weight: 700;
}

.connection-status {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 0.25rem;
}

#status {
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.875rem;
    font-weight: 500;
    background: var(--danger-color);
    color: white;
}

#status.connected {
    background: var(--success-color);
}

#player-id {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* Screen Management */
.screen {
    display: none;
}

.screen.active {
    display: block;
}

/* Connection Screen */
.connection-card {
    background: var(--surface);
    border-radius: 16px;
    padding: 3rem;
    box-shadow: var(--shadow-lg);
    max-width: 500px;
    margin: 0 auto;
    text-align: center;
}

.connection-card h2 {
    margin-bottom: 2rem;
    color: var(--primary-color);
    font-size: 1.75rem;
}

.connection-options {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.option {
    padding: 1.5rem;
    border: 2px solid var(--border);
    border-radius: 12px;
    transition: border-color 0.2s;
}

.option:hover {
    border-color: var(--primary-color);
}

.option p {
    margin-top: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

input {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border);
    border-radius: 8px;
    font-size: 1rem;
    margin-bottom: 1rem;
    transition: border-color 0.2s;
}

input:focus {
    outline: none;
    border-color: var(--primary-color);
}

/* Buttons */
.primary-btn, .secondary-btn, .control-btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.primary-btn {
    background: var(--primary-color);
    color: white;
}

.primary-btn:hover:not(:disabled) {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

.primary-btn:disabled {
    background: var(--text-secondary);
    cursor: not-allowed;
}

.secondary-btn {
    background: var(--surface);
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.secondary-btn:hover {
    background: var(--primary-color);
    color: white;
}

.control-btn {
    background: var(--secondary-color);
    color: white;
    font-size: 0.875rem;
    padding: 0.5rem 1rem;
}

.control-btn:hover {
    background: var(--text-primary);
}

.room-info {
    margin-top: 2rem;
    padding: 1rem;
    background: var(--primary-color);
    color: white;
    border-radius: 8px;
}

.room-info.hidden {
    display: none;
}

/* Ship Placement Screen */
.placement-container {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 2rem;
    background: var(--surface);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
}

.placement-container h2 {
    grid-column: 1 / -1;
    text-align: center;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

/* Ship Preview Area (like Tetris next piece) */
.ship-preview-area {
    grid-column: 1 / -1;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-hover));
    border-radius: 12px;
    padding: 1.5rem;
    text-align: center;
    margin-bottom: 1rem;
    box-shadow: var(--shadow);
    display: none; /* Hidden by default on desktop */
}

.ship-preview-area h3 {
    color: white;
    margin-bottom: 1rem;
    font-size: 1.1rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.current-ship-display {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    padding: 1rem;
    backdrop-filter: blur(10px);
}

#preview-ship-name {
    display: block;
    color: white;
    font-weight: 600;
    margin-bottom: 0.75rem;
    font-size: 1.1rem;
}

.preview-ship-visual {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 40px;
    gap: 4px;
}

.preview-ship-visual.horizontal {
    flex-direction: row;
}

.preview-ship-visual.vertical {
    flex-direction: column;
}

.preview-ship-visual .ship-block {
    width: 24px;
    height: 24px;
    background: white;
    border-radius: 3px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
    transition: all 0.2s ease;
}

.preview-ship-visual.vertical .ship-block {
    width: 24px;
    height: 24px;
}

.ship-preview-area.selected {
    animation: pulseGlow 2s infinite;
}

@keyframes pulseGlow {
    0%, 100% { 
        box-shadow: var(--shadow), 0 0 20px rgba(37, 99, 235, 0.5);
    }
    50% { 
        box-shadow: var(--shadow), 0 0 30px rgba(37, 99, 235, 0.8);
    }
}

.ship-selection {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.ships-to-place {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.ship-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem;
    border: 2px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

.ship-item:hover {
    border-color: var(--primary-color);
    background: rgba(37, 99, 235, 0.05);
}

.ship-item.selected {
    border-color: var(--primary-color);
    background: rgba(37, 99, 235, 0.1);
}

.ship-item.placed {
    opacity: 0.5;
    cursor: not-allowed;
}

.ship-preview {
    display: flex;
    gap: 2px;
}

.ship-preview.horizontal {
    flex-direction: row;
}

.ship-preview.vertical {
    flex-direction: column;
}

.ship-preview::before {
    content: '';
    display: flex;
    gap: 2px;
}

.ship-preview[data-size="5"]::before {
    content: '■ ■ ■ ■ ■';
}

.ship-preview[data-size="4"]::before {
    content: '■ ■ ■ ■';
}

.ship-preview[data-size="3"]::before {
    content: '■ ■ ■';
}

.ship-preview[data-size="2"]::before {
    content: '■ ■';
}

.placement-controls {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

/* Placement Status Section */
.placement-status {
    margin-top: 1.5rem;
    padding: 1rem;
    background: var(--background);
    border-radius: 8px;
    border: 2px solid var(--border);
}

.placement-status h4 {
    margin: 0 0 1rem 0;
    color: var(--text-primary);
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    text-align: center;
}

.status-indicators {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.player-status-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.status-label {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 0.9rem;
}

.status-badge {
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.status-badge.ready {
    background: var(--success-color);
    color: white;
}

.status-badge.not-ready {
    background: var(--secondary-color);
    color: white;
}

.status-badge.waiting {
    background: var(--accent-color);
    color: white;
}

/* Game Screen */
#game-screen {
    background: var(--surface);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
}

.game-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    background: var(--background);
    border-radius: 8px;
}

.turn-indicator {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
}

.game-stats {
    display: flex;
    gap: 2rem;
}

.stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
}

.stat span:first-child {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.stat span:last-child {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.boards-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    margin-bottom: 2rem;
}

.board-section h3 {
    text-align: center;
    margin-bottom: 1rem;
    color: var(--text-primary);
    font-size: 1.25rem;
}

/* Game Boards */
.board {
    display: grid;
    grid-template-columns: repeat(10, 1fr);
    gap: 2px;
    background: var(--border);
    padding: 8px;
    border-radius: 8px;
    aspect-ratio: 1;
    max-width: 400px;
    margin: 0 auto;
}

.cell {
    background: var(--water-color);
    border: 1px solid rgba(255, 255, 255, 0.3);
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    aspect-ratio: 1;
    min-height: 0;
}

.cell:hover {
    background: rgba(37, 99, 235, 0.8);
    transform: scale(1.05);
}

.cell.ship {
    background: var(--ship-color);
}

.cell.hit {
    background: var(--hit-color);
}

.cell.hit::after {
    content: '🔥';
    font-size: 1em;
}

.cell.miss {
    background: var(--miss-color);
}

.cell.miss::after {
    content: '💧';
    font-size: 1em;
}

.cell.sunk {
    background: var(--danger-color);
}

.cell.sunk::after {
    content: '💀';
    font-size: 0.8em;
}

.enemy-board .cell {
    cursor: crosshair;
}

.enemy-board .cell.hit,
.enemy-board .cell.miss,
.enemy-board .cell.sunk {
    cursor: not-allowed;
}

.enemy-board.not-your-turn {
    opacity: 0.5;
    filter: grayscale(50%);
}

.enemy-board.not-your-turn .cell {
    cursor: not-allowed;
}

.enemy-board.not-your-turn .cell:hover {
    background: var(--water-color);
    transform: none;
}

/* Shooting Animation */
.enemy-board.shooting {
    pointer-events: none;
    opacity: 0.7;
}

.cell.shooting-animation {
    position: relative;
    overflow: visible;
    animation: missile-approach 0.8s ease-out forwards;
}

.cell.shooting-animation::before {
    content: '💥';
    position: absolute;
    font-size: 2em;
    z-index: 10;
    animation: missile-trail 0.8s ease-out forwards;
    opacity: 0;
}

@keyframes missile-approach {
    0% {
        background: var(--water-color);
        box-shadow: 0 0 0 0 rgba(239, 68, 68, 0);
    }
    50% {
        background: rgba(239, 68, 68, 0.3);
        box-shadow: 0 0 20px 5px rgba(239, 68, 68, 0.5);
        transform: scale(1.1);
    }
    100% {
        background: var(--water-color);
        box-shadow: 0 0 0 0 rgba(239, 68, 68, 0);
        transform: scale(1);
    }
}

@keyframes missile-trail {
    0% {
        opacity: 0;
        transform: scale(0) translateY(-50px);
    }
    50% {
        opacity: 1;
        transform: scale(1.2) translateY(0);
    }
    100% {
        opacity: 0;
        transform: scale(1) translateY(0);
    }
}

/* Result Reveal Animation */
.cell.result-reveal {
    animation: result-pulse 0.5s ease-out;
}

.cell.hit-animation {
    animation: hit-explosion 0.6s ease-out;
}

.cell.miss-animation {
    animation: miss-splash 0.6s ease-out;
}

@keyframes result-pulse {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.15);
    }
    100% {
        transform: scale(1);
    }
}

@keyframes hit-explosion {
    0% {
        background: var(--water-color);
        box-shadow: 0 0 0 0 rgba(239, 68, 68, 0);
        transform: scale(1);
    }
    30% {
        box-shadow: 0 0 30px 10px rgba(239, 68, 68, 0.8);
        transform: scale(1.2);
    }
    60% {
        background: var(--hit-color);
        box-shadow: 0 0 20px 5px rgba(239, 68, 68, 0.6);
        transform: scale(1.1);
    }
    100% {
        background: var(--hit-color);
        box-shadow: 0 0 0 0 rgba(239, 68, 68, 0);
        transform: scale(1);
    }
}

@keyframes miss-splash {
    0% {
        background: var(--water-color);
        box-shadow: 0 0 0 0 rgba(100, 116, 139, 0);
        transform: scale(1);
    }
    30% {
        box-shadow: 0 0 25px 8px rgba(100, 116, 139, 0.6);
        transform: scale(1.15);
    }
    60% {
        background: var(--miss-color);
        box-shadow: 0 0 15px 4px rgba(100, 116, 139, 0.4);
        transform: scale(1.05);
    }
    100% {
        background: var(--miss-color);
        box-shadow: 0 0 0 0 rgba(100, 116, 139, 0);
        transform: scale(1);
    }
}

/* Incoming Attack Animation (when you're being shot) */
.cell.incoming-attack-animation {
    position: relative;
    animation: incoming-warning 0.8s ease-out forwards;
    z-index: 5;
}

.cell.incoming-attack-animation::before {
    content: '⚠️';
    position: absolute;
    font-size: 1.5em;
    z-index: 10;
    animation: incoming-alert 0.8s ease-out forwards;
    opacity: 0;
}

@keyframes incoming-warning {
    0% {
        background: var(--water-color);
        box-shadow: 0 0 0 0 rgba(245, 158, 11, 0);
        border: 1px solid rgba(255, 255, 255, 0.3);
    }
    25% {
        background: rgba(245, 158, 11, 0.2);
        box-shadow: 0 0 15px 5px rgba(245, 158, 11, 0.5);
        border: 2px solid rgba(245, 158, 11, 0.8);
        transform: scale(1.05);
    }
    50% {
        background: rgba(239, 68, 68, 0.3);
        box-shadow: 0 0 25px 8px rgba(239, 68, 68, 0.6);
        border: 2px solid rgba(239, 68, 68, 0.9);
        transform: scale(1.1);
    }
    75% {
        background: rgba(239, 68, 68, 0.4);
        box-shadow: 0 0 30px 10px rgba(239, 68, 68, 0.7);
        border: 2px solid rgba(239, 68, 68, 1);
        transform: scale(1.08);
    }
    100% {
        background: var(--water-color);
        box-shadow: 0 0 0 0 rgba(239, 68, 68, 0);
        border: 1px solid rgba(255, 255, 255, 0.3);
        transform: scale(1);
    }
}

@keyframes incoming-alert {
    0% {
        opacity: 0;
        transform: scale(0) translateY(-30px) rotate(0deg);
    }
    30% {
        opacity: 1;
        transform: scale(1.3) translateY(-10px) rotate(15deg);
    }
    60% {
        opacity: 1;
        transform: scale(1.2) translateY(0) rotate(-10deg);
    }
    100% {
        opacity: 0;
        transform: scale(1) translateY(0) rotate(0deg);
    }
}

/* Placement Board */
.placement-board .cell.valid-placement {
    background: rgba(16, 185, 129, 0.5);
}

.placement-board .cell.invalid-placement {
    background: rgba(239, 68, 68, 0.5);
}

/* Game Over Screen */
.game-over-container {
    background: var(--surface);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
    max-width: 1000px;
    margin: 0 auto;
    text-align: center;
}

.game-over-header {
    margin-bottom: 2rem;
}

.game-over-header h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--success-color);
}

.game-over-header h2.defeat {
    color: var(--danger-color);
}

.game-over-header p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 0;
}

/* Final Boards Display */
.final-boards-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    margin: 2rem 0;
    padding: 1.5rem;
    background: var(--background);
    border-radius: 12px;
}

.final-board-section h3 {
    text-align: center;
    margin-bottom: 1rem;
    color: var(--text-primary);
    font-size: 1.1rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.final-player-board,
.final-enemy-board {
    max-width: 300px;
    margin: 0 auto;
}

/* Show all ships on final boards */
.final-enemy-board .cell.ship {
    background: var(--ship-color);
}

.final-enemy-board .cell.ship.hit {
    background: var(--hit-color);
}

.final-enemy-board .cell.ship.sunk {
    background: var(--danger-color);
}

.game-over-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-top: 2rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .game-container {
        padding: 10px;
    }
    
    header {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
    
    .connection-status {
        align-items: center;
    }
    
    .placement-container {
        grid-template-columns: 1fr;
    }
    
    /* Make ship preview area visible and prominent on mobile */
    .ship-preview-area {
        display: block; /* Show on mobile */
        position: sticky;
        top: 10px;
        z-index: 10;
        margin-bottom: 1.5rem;
        border: 3px solid rgba(255, 255, 255, 0.3);
    }
    
    .ship-preview-area h3 {
        font-size: 1.2rem;
        margin-bottom: 1.2rem;
    }
    
    .current-ship-display {
        padding: 1.5rem;
    }
    
    #preview-ship-name {
        font-size: 1.3rem;
        margin-bottom: 1rem;
    }
    
    .preview-ship-visual .ship-block {
        width: 28px;
        height: 28px;
    }
    
    .boards-container {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .board {
        max-width: 300px;
    }
    
    .game-info {
        flex-direction: column;
        gap: 1rem;
    }
    
    .game-stats {
        justify-content: center;
    }
    
    /* Game Over Screen Mobile */
    .game-over-container {
        padding: 1.5rem;
        max-width: 100%;
    }
    
    .game-over-header h2 {
        font-size: 2rem;
    }
    
    .final-boards-container {
        grid-template-columns: 1fr;
        gap: 2rem;
        margin: 1.5rem 0;
        padding: 1rem;
    }
    
    .final-player-board,
    .final-enemy-board {
        max-width: 280px;
    }
}

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

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.screen.active {
    animation: fadeIn 0.3s ease-out;
}

.cell.hit {
    animation: hitFlash 0.3s ease-out;
}

@keyframes hitFlash {
    0%, 100% { background: var(--hit-color); }
    50% { background: rgba(239, 68, 68, 0.8); }
}

.ship-item.selected {
    animation: pulse 1s infinite;
}