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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #ffffff;
    color: #333;
}

a {
    text-decoration: none;
    padding: 10px;
}

.container {
    max-width: 100%;
    margin: 0 auto;
    padding: 25px 35px;
}

button {
    padding: 10px 20px;
    background: #3b7dff;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

button:hover {
    background: #5c8ff6;
}

.btn-primary, .btn-secondary {
    padding: 15px 30px;
    font-size: 18px;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-primary {
    background: #3498db;
    color: white;
}

.btn-primary:hover {
    background: #2980b9;
}

.btn-secondary {
    background: #95a5a6;
    color: white;
}

.btn-secondary:hover {
    background: #7f8c8d;
}

/* nav */
.navbar {
    background: #667889;
    padding: 15px 0;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.nav-container {
    max-width: 100%;
    margin: 0;
    padding: 0px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo a {
    color: white;
    text-decoration: none;
    font-size: 24px;
    font-weight: bold;
}

.nav-menu {
    list-style: none;
    display: flex;
    gap: 30px;
    margin: 0;
    padding: 0;
}

.nav-menu li a {
    color: #ecf0f1;
    text-decoration: none;
    font-size: 16px;
    transition: color 0.3s;
}

.nav-menu li a:hover {
    color: #6eafda;
}

/* footer */
.footer {
    background: #667889;
    padding: 20px 10px;
    margin-top: 50px;
    box-shadow: 0 -2px 5px rgba(0,0,0,0.1);
}

.footer-container {
    display: flex;
    justify-content: center;
    align-items: center;
}

.footer p {
    color: #ecf0f1;
    font-size: 14px;
    margin: 0;
}

/* matchmaking */
.matchmaking-wrapper {
    text-align: center;
    padding: 40px 20px;
}

.matchmaking-wrapper h1 {
    font-size: 42px;
    margin-bottom: 10px;
    color: #667889;
}

.subtitle {
    font-size: 18px;
    color: #667889;
    margin-bottom: 50px;
}

.game-modes {
    display: flex;
    gap: 30px;
    justify-content: center;
    flex-wrap: wrap;
}

.mode-card {
    background: white;
    border: 2px solid #ecf0f1;
    border-radius: 15px;
    padding: 40px 30px;
    width: 280px;
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.mode-card:hover {
    border-color: #3498db;
    box-shadow: 0 5px 20px rgba(52, 152, 219, 0.3);
}

.mode-icon {
    font-size: 64px;
    margin-bottom: 20px;
}

.mode-card h2 {
    font-size: 28px;
    margin-bottom: 10px;
    color: #667889;
}

.mode-card p {
    font-size: 16px;
    color: #667889;
    margin: 0;
}

/* lobby */
.lobby-wrapper {
    text-align: center;
    padding: 40px 20px;
    max-width: 900px;
    margin: 0 auto;
}

.lobby-wrapper h1 {
    font-size: 42px;
    margin-bottom: 10px;
    color: #2c3e50;
}

.lobby-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.lobby-card {
    background: white;
    border: 2px solid #ecf0f1;
    border-radius: 15px;
    padding: 2rem 1.5rem;
    text-align: center;
    transition: all 0.3s;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.lobby-card:hover {
    border-color: #3498db;
    box-shadow: 0 5px 20px rgba(52, 152, 219, 0.3);
}

.lobby-card-icon {
    font-size: 2.5rem;
    margin-bottom: 0.75rem;
}

.lobby-card h2 {
    font-size: 1.3rem;
    margin: 0.25rem 0 0.5rem;
    color: #667889;
}

.lobby-card p {
    font-size: 0.9rem;
    color: #667889;
    margin-bottom: 1.25rem;
}

.lobby-panel {
    margin-top: 2rem;
    background: #f8f9fa;
    border: 2px solid #ecf0f1;
    border-radius: 15px;
    padding: 1.5rem;
    max-width: 480px;
    margin-left: auto;
    margin-right: auto;
    animation: slideIn 0.2s ease;
}

@keyframes slideIn {
    from { opacity: 0; transform: translateY(12px); }
    to   { opacity: 1; transform: translateY(0); }
}

.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.25rem;
}

.panel-header h3 {
    margin: 0;
    font-size: 1.1rem;
    color: #2c3e50;
}

.btn-close {
    background: none;
    border: none;
    font-size: 1.1rem;
    cursor: pointer;
    opacity: 0.5;
    transition: opacity 0.15s;
    color: #333;
    padding: 0.25rem 0.5rem;
}
.btn-close:hover { opacity: 1; background: none; }

.panel-label {
    display: block;
    font-size: 0.85rem;
    color: #667889;
    margin-bottom: 0.5rem;
    text-align: left;
}

.panel-hint {
    font-size: 0.82rem;
    color: #95a5a6;
    margin-top: 0.5rem;
    text-align: left;
}

.panel-error {
    font-size: 0.85rem;
    color: #e74c3c;
    margin-top: 0.5rem;
    text-align: left;
}

.room-code-display {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: #ecf0f1;
    border: 2px solid #dde1e7;
    border-radius: 8px;
    padding: 0.75rem 1rem;
}

#room-code-text {
    font-size: 1.8rem;
    font-family: monospace;
    letter-spacing: 0.15em;
    flex: 1;
    text-align: center;
    color: #3498db;
}

.btn-copy {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    transition: transform 0.15s;
    padding: 0;
}
.btn-copy:hover { transform: scale(1.2); background: none; }

.code-input {
    width: 100%;
    padding: 0.75rem 1rem;
    font-size: 1.4rem;
    font-family: monospace;
    letter-spacing: 0.2em;
    text-align: center;
    background: #ecf0f1;
    border: 2px solid #dde1e7;
    border-radius: 8px;
    color: #2c3e50;
    outline: none;
    box-sizing: border-box;
    transition: border-color 0.2s;
}
.code-input:focus { border-color: #3498db; }

.toggle-label {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    cursor: pointer;
    font-size: 0.95rem;
    margin-top: 1rem;
    color: #2c3e50;
}
.toggle-label input { display: none; }

.toggle-slider {
    position: relative;
    width: 44px;
    height: 24px;
    background: #bdc3c7;
    border-radius: 999px;
    flex-shrink: 0;
    transition: background 0.2s;
}
.toggle-slider::after {
    content: '';
    position: absolute;
    top: 3px; left: 3px;
    width: 18px; height: 18px;
    background: #fff;
    border-radius: 50%;
    transition: left 0.2s;
}
.toggle-label input:checked + .toggle-slider { background: #3498db; }
.toggle-label input:checked + .toggle-slider::after { left: 23px; }

/* game */
.game-wrapper {
    max-width: 700px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

.game-wrapper {
    max-width: 450px;
    margin: 0;
    padding: 2rem 1rem;
}
.game-state {
    background: white;
    border: 2px solid #ecf0f1;
    border-radius: 15px;
    padding: 1.5rem 2rem;
    margin-bottom: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.game-state p {
    color: #2c3e50;
    font-size: 1rem;
}

.game-state span {
    color: #2c3e50;
    font-weight: bold;
}
.game-board {
    background: white;
    border: 2px solid #ecf0f1;
    border-radius: 15px;
    padding: 1.5rem 2rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.game-board p {
    color: #2c3e50;
    font-size: 1rem;
}

.game-board span {
    color: #2c3e50;
    font-weight: bold;
}