/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --secondary-color: #7c3aed;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --bg-color: #0f172a;
    --surface-color: #1e293b;
    --text-color: #f1f5f9;
    --border-color: #334155;
    --water-color: #3b82f6;
    --ship-color: #64748b;
    --hit-color: #ef4444;
    --miss-color: #94a3b8;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica', 'Arial', sans-serif;
    background: linear-gradient(135deg, var(--bg-color) 0%, #1e40af 100%);
    color: var(--text-color);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 1rem;
    overflow-x: hidden;
}

/* Screen Management */
.screen {
    display: none;
    width: 100%;
    max-width: 1200px;
    animation: fadeIn 0.3s ease-in;
}

.screen.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Container */
.container {
    background: var(--surface-color);
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    text-align: center;
}

h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    color: var(--water-color);
}

h2 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    color: var(--water-color);
}

h3 {
    font-size: 1.2rem;
    margin-bottom: 0.75rem;
}

.subtitle {
    color: var(--miss-color);
    margin-bottom: 2rem;
}

/* Game Size Selector */
.game-size-selector {
    margin-bottom: 1.5rem;
}

.game-size-selector > label {
    display: block;
    margin-bottom: 0.75rem;
    font-weight: 600;
}

.size-options {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.size-option {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    background: var(--bg-color);
    border-radius: 0.5rem;
    cursor: pointer;
    transition: background 0.2s;
}

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

.size-option input[type="radio"] {
    width: 1.25rem;
    height: 1.25rem;
    accent-color: var(--primary-color);
}

.size-option .size-label {
    font-weight: 600;
    min-width: 70px;
}

.size-option .size-desc {
    color: var(--miss-color);
    font-size: 0.875rem;
}

@media (min-width: 768px) {
    .size-options {
        flex-direction: row;
        justify-content: center;
    }

    .size-option {
        flex: 0 0 auto;
    }
}

/* Buttons */
.btn {
    padding: 0.875rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
    min-width: 140px;
    touch-action: manipulation;
}

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

.btn-primary:hover:not(:disabled) {
    background: #1d4ed8;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.4);
}

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

.btn-secondary:hover:not(:disabled) {
    background: #6d28d9;
}

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

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.button-group {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

/* Input */
input[type="text"] {
    padding: 0.875rem;
    font-size: 1.125rem;
    border: 2px solid var(--border-color);
    border-radius: 0.5rem;
    background: var(--bg-color);
    color: var(--text-color);
    text-align: center;
    text-transform: uppercase;
    letter-spacing: 0.2em;
    width: 100%;
    margin-bottom: 1rem;
}

input[type="text"]:focus {
    outline: none;
    border-color: var(--primary-color);
}

/* Room Code Display */
.room-code-display {
    margin: 2rem 0;
}

.room-code {
    font-size: 3rem;
    font-weight: bold;
    letter-spacing: 0.3em;
    color: var(--primary-color);
    background: var(--bg-color);
    padding: 1rem;
    border-radius: 0.5rem;
    margin: 1rem 0;
    user-select: all;
}

/* Spinner */
.spinner {
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
    margin: 2rem auto;
}

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

/* Board */
.board {
    display: grid;
    grid-template-columns: repeat(10, 1fr);
    gap: 2px;
    background: var(--border-color);
    border: 2px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 2px;
    margin: 1rem auto;
    max-width: 400px;
    aspect-ratio: 1;
}

.board.board-8 {
    grid-template-columns: repeat(8, 1fr);
}

.board.board-9 {
    grid-template-columns: repeat(9, 1fr);
}

.board.board-10 {
    grid-template-columns: repeat(10, 1fr);
}

.cell {
    background: var(--water-color);
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 1.2rem;
    position: relative;
}

.cell:hover {
    filter: brightness(1.2);
}

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

/* Ship Graphics - Segments */
.cell.ship-segment {
    background: var(--water-color);
    position: relative;
}

.cell.ship-segment::before {
    content: '';
    position: absolute;
    background: var(--ship-color);
    border: 2px solid #475569;
    box-sizing: border-box;
}

/* Horizontal ship segments */
.cell.ship-h.ship-bow::before {
    top: 15%;
    bottom: 15%;
    left: 5%;
    right: 0;
    border-radius: 50% 0 0 50%;
    border-right: none;
}

.cell.ship-h.ship-mid::before {
    top: 15%;
    bottom: 15%;
    left: 0;
    right: 0;
    border-radius: 0;
    border-left: none;
    border-right: none;
}

.cell.ship-h.ship-stern::before {
    top: 15%;
    bottom: 15%;
    left: 0;
    right: 5%;
    border-radius: 0 30% 30% 0;
    border-left: none;
}

/* Reversed bow for back of battleship/submarine (horizontal) */
.cell.ship-h.ship-bow-end::before {
    top: 15%;
    bottom: 15%;
    left: 0;
    right: 5%;
    border-radius: 0 50% 50% 0;
    border-left: none;
}

/* Reversed stern for front of carrier (horizontal) - rotated 180deg */
.cell.ship-h.ship-stern-front::before {
    top: 15%;
    bottom: 15%;
    left: 5%;
    right: 0;
    border-radius: 30% 0 0 30%;
    border-right: none;
}

/* Vertical ship segments */
.cell.ship-v.ship-bow::before {
    left: 15%;
    right: 15%;
    top: 5%;
    bottom: 0;
    border-radius: 50% 50% 0 0;
    border-bottom: none;
}

.cell.ship-v.ship-mid::before {
    left: 15%;
    right: 15%;
    top: 0;
    bottom: 0;
    border-radius: 0;
    border-top: none;
    border-bottom: none;
}

.cell.ship-v.ship-stern::before {
    left: 15%;
    right: 15%;
    top: 0;
    bottom: 5%;
    border-radius: 0 0 30% 30%;
    border-top: none;
}

/* Reversed bow for back of battleship/submarine (vertical) */
.cell.ship-v.ship-bow-end::before {
    left: 15%;
    right: 15%;
    top: 0;
    bottom: 5%;
    border-radius: 0 0 50% 50%;
    border-top: none;
}

/* Reversed stern for front of carrier (vertical) - rotated 180deg */
.cell.ship-v.ship-stern-front::before {
    left: 15%;
    right: 15%;
    top: 5%;
    bottom: 0;
    border-radius: 30% 30% 0 0;
    border-bottom: none;
}

/* Single cell ship (Destroyer can look like a small boat) */
.cell.ship-h.ship-single::before,
.cell.ship-v.ship-single::before {
    top: 15%;
    bottom: 15%;
    left: 10%;
    right: 10%;
    border-radius: 40%;
    border: 2px solid #475569;
}

/* Ship details - add some deck lines */
.cell.ship-segment::after {
    content: '';
    position: absolute;
    background: #475569;
    opacity: 0.5;
}

.cell.ship-h.ship-mid::after {
    top: 45%;
    height: 10%;
    left: 10%;
    right: 10%;
}

.cell.ship-v.ship-mid::after {
    left: 45%;
    width: 10%;
    top: 10%;
    bottom: 10%;
}

/* Preview segments */
.cell.preview.ship-segment::before {
    background: rgba(100, 116, 139, 0.6);
    border-color: rgba(71, 85, 105, 0.6);
}

.cell.invalid.ship-segment::before {
    background: rgba(239, 68, 68, 0.5);
    border-color: rgba(185, 28, 28, 0.6);
}

/* Hit marker on ship - fire/damage effect */
.cell.ship-segment.hit::before {
    background: linear-gradient(135deg, #7f1d1d 0%, var(--hit-color) 50%, #991b1b 100%);
    box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.5);
}

.cell.ship-segment.hit::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60%;
    height: 60%;
    background: radial-gradient(circle, #fbbf24 0%, #f97316 40%, #ef4444 70%, transparent 100%);
    border-radius: 50%;
    animation: shipFire 1s ease-in-out infinite alternate;
    opacity: 1;
}

@keyframes shipFire {
    0% { transform: translate(-50%, -50%) scale(0.8); opacity: 0.9; }
    100% { transform: translate(-50%, -50%) scale(1.1); opacity: 1; }
}

/* Hit indicator - explosion effect */
.cell.hit {
    background: var(--hit-color);
    position: relative;
    overflow: visible;
}

.cell.hit::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 70%;
    height: 70%;
    background: radial-gradient(circle, #fbbf24 0%, #f97316 40%, #ef4444 70%, transparent 100%);
    border-radius: 50%;
    z-index: 2;
    animation: hitPulse 1.5s ease-out infinite;
}

.cell.hit::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 40%;
    height: 40%;
    background: #fef3c7;
    border-radius: 50%;
    box-shadow:
        0 0 4px 2px #fbbf24,
        0 0 8px 4px rgba(251, 191, 36, 0.5);
    z-index: 3;
}

@keyframes hitPulse {
    0% { opacity: 1; transform: translate(-50%, -50%) scale(1); }
    50% { opacity: 0.8; transform: translate(-50%, -50%) scale(1.1); }
    100% { opacity: 1; transform: translate(-50%, -50%) scale(1); }
}

/* Miss indicator - water splash effect */
.cell.miss {
    background: var(--water-color);
    position: relative;
    overflow: hidden;
}

.cell.miss::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60%;
    height: 60%;
    border: 3px solid rgba(255, 255, 255, 0.6);
    border-radius: 50%;
    background: transparent;
    box-shadow:
        0 0 0 2px rgba(255, 255, 255, 0.3),
        inset 0 0 8px rgba(255, 255, 255, 0.2);
}

.cell.miss::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 25%;
    height: 25%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.8) 0%, rgba(255, 255, 255, 0.4) 50%, transparent 100%);
    border-radius: 50%;
}

/* Outer ripple for miss */
.cell.miss.ripple-animate::before {
    animation: ripple 2s ease-out infinite;
}

@keyframes ripple {
    0% { transform: translate(-50%, -50%) scale(0.8); opacity: 1; }
    100% { transform: translate(-50%, -50%) scale(1.3); opacity: 0; }
}

.cell.preview {
    background: rgba(100, 116, 139, 0.5);
}

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

.board.targeting .cell:not(.hit):not(.miss):hover {
    background: rgba(59, 130, 246, 0.7);
}

/* Setup Screen */
.ships-info {
    background: var(--bg-color);
    padding: 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1.5rem;
    text-align: left;
}

.ships-info ul {
    list-style: none;
    margin-top: 0.5rem;
}

.ships-info li {
    padding: 0.5rem;
    margin: 0.25rem 0;
    background: var(--surface-color);
    border-radius: 0.25rem;
}

.ships-info li.placed {
    opacity: 0.5;
    text-decoration: line-through;
}

.setup-controls {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-top: 1.5rem;
}

.ship-selector, .orientation-toggle {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

select {
    padding: 0.5rem;
    font-size: 1rem;
    border-radius: 0.375rem;
    background: var(--bg-color);
    color: var(--text-color);
    border: 2px solid var(--border-color);
    flex: 1;
}

.instruction {
    margin-top: 1rem;
    color: var(--miss-color);
    font-size: 0.875rem;
}

/* Game Screen */
.game-container {
    background: var(--surface-color);
    border-radius: 1rem;
    padding: 1.5rem;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
}

.turn-indicator {
    background: var(--bg-color);
    padding: 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1.5rem;
}

#turn-status {
    font-size: 1.125rem;
    font-weight: 600;
}

.boards-container {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.board-section {
    flex: 1;
}

/* Game Log */
.game-log {
    margin-top: 2rem;
    background: var(--bg-color);
    border-radius: 0.5rem;
    padding: 1rem;
    max-height: 200px;
    overflow-y: auto;
}

.game-log h4 {
    margin-bottom: 0.5rem;
}

#log-messages {
    text-align: left;
    font-size: 0.875rem;
}

.log-entry {
    padding: 0.5rem;
    margin: 0.25rem 0;
    border-radius: 0.25rem;
    background: var(--surface-color);
}

.log-entry.hit {
    color: var(--hit-color);
    border-left: 3px solid var(--hit-color);
}

.log-entry.miss {
    color: var(--miss-color);
    border-left: 3px solid var(--miss-color);
}

.log-entry.sunk {
    color: var(--danger-color);
    font-weight: bold;
    border-left: 3px solid var(--danger-color);
}

/* Notification Toast */
.notification {
    position: fixed;
    top: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background: var(--surface-color);
    color: var(--text-color);
    padding: 1rem 2rem;
    border-radius: 0.5rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    z-index: 1000;
    animation: slideDown 0.3s ease-out;
}

.notification.hidden {
    display: none;
}

@keyframes slideDown {
    from {
        transform: translate(-50%, -100%);
        opacity: 0;
    }
    to {
        transform: translate(-50%, 0);
        opacity: 1;
    }
}

/* Utility Classes */
.hidden {
    display: none !important;
}

.waiting-text {
    margin: 1rem 0;
    color: var(--miss-color);
}

/* Desktop Styles */
@media (min-width: 768px) {
    .button-group {
        flex-direction: row;
        justify-content: center;
    }

    .boards-container {
        flex-direction: row;
        gap: 2rem;
    }

    .board {
        max-width: 350px;
    }

    .setup-controls {
        flex-direction: row;
        flex-wrap: wrap;
        align-items: center;
        justify-content: center;
    }

    .ship-selector, .orientation-toggle {
        flex: 0 0 auto;
    }

    .room-code {
        font-size: 4rem;
    }

    h1 {
        font-size: 3.5rem;
    }
}

@media (min-width: 1024px) {
    .board {
        max-width: 400px;
    }

    .game-container {
        padding: 2rem;
    }
}

/* Prevent text selection on game elements */
.board, .btn, .cell {
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}

/* Reconnect Prompt */
.reconnect-prompt {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    animation: fadeIn 0.3s ease-out;
}

.reconnect-content {
    background: var(--surface-color);
    border-radius: 1rem;
    padding: 2rem;
    text-align: center;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    max-width: 400px;
    width: 90%;
}

.reconnect-content h3 {
    color: var(--water-color);
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.reconnect-content p {
    color: var(--text-color);
    margin-bottom: 1.5rem;
}

.reconnect-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.reconnect-buttons .btn {
    min-width: 120px;
}