body {
    margin: 0;
    overflow: hidden;
    background: #1a1a1a;
    font-family: 'Segoe UI', sans-serif;
    user-select: none;
}

canvas {
    display: block;
}

#init-screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;

    /* THAY background: #111; THÀNH: */
    background: linear-gradient(rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.6)), url('music/nen_sanh.jpg') no-repeat center center;
    background-size: cover;

    color: #3498db;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 30;
    cursor: pointer;
}

#lobby-screen {
    position: absolute !important;
    top: 0 !important;
    left: 0 !important;
    width: 100vw !important;
    height: 100vh !important;

    /* ĐƯỜNG DẪN: Nếu file nằm trong thư mục music thì dùng 'music/nen_sanh.jpg' */
    /* Nếu vẫn không hiện, bạn hãy thử đổi thành 'nen_sanh.jpg' */
    background-image: url('music/nen_sanh.jpg') !important;
    background-size: cover !important;
    background-position: center !important;
    background-repeat: no-repeat !important;

    /* Căn giữa toàn bộ nội dung trong sảnh */
    display: none;
    /* Giữ nguyên để JS điều khiển */
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 20;
}

#player-name-input {
    padding: 15px 25px;
    font-size: 20px;
    border-radius: 30px;
    border: 2px solid #f39c12;
    background: rgba(0, 0, 0, 0.5);
    color: white;
    outline: none;
    text-align: center;
    width: 300px;
    margin-bottom: 30px;
    transition: 0.3s;
}

#player-name-input:focus {
    box-shadow: 0 0 15px #f1c40f;
}

.tank-selection {
    display: flex;
    overflow-x: auto;
    gap: 15px;
    padding: 10px 5px 20px 5px;
    margin-bottom: 20px;
    scroll-snap-type: x mandatory;
    scroll-behavior: smooth;
    max-width: 1000px;
}

.tank-selection::-webkit-scrollbar {
    height: 10px;
}

.tank-selection::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 10px;
}

.tank-selection::-webkit-scrollbar-thumb {
    background: #e67e22;
    border-radius: 10px;
    border: 2px solid #1a1a1a;
}

.tank-selection::-webkit-scrollbar-thumb:hover {
    background: #f1c40f;
}

.tank-card {
    width: 160px;
    height: 220px;
    flex: 0 0 200px;
    scroll-snap-align: start;
    background: rgba(0, 0, 0, 0.7);
    border: 3px solid #555;
    border-radius: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
    cursor: pointer;
    transition: 0.3s;
    position: relative;
    overflow: hidden;
}

.tank-card:hover {
    transform: translateY(-10px);
    border-color: #f1c40f;
    box-shadow: 0 10px 20px rgba(241, 196, 15, 0.4);
}

.tank-card.selected {
    border-color: #2ecc71;
    box-shadow: 0 0 30px rgba(46, 204, 113, 0.6);
}

.tank-icon {
    width: 100%;
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 50px;
    background: #222;
}

.tank-name {
    color: white;
    font-weight: bold;
    font-size: 18px;
    margin-top: 15px;
    text-transform: uppercase;
}

.tank-desc {
    color: #aaa;
    font-size: 12px;
    text-align: center;
    padding: 0 10px;
    margin-top: 5px;
}

#start-btn {
    padding: 15px 50px;
    font-size: 24px;
    font-weight: bold;
    background: linear-gradient(45deg, #e67e22, #f1c40f);
    border: none;
    border-radius: 40px;
    color: #000;
    cursor: pointer;
    box-shadow: 0 0 20px #e67e22;
    transition: 0.2s;
}

#start-btn:hover {
    transform: scale(1.05);
    filter: brightness(1.2);
}

#start-btn:disabled {
    background: #555;
    color: #888;
    box-shadow: none;
    cursor: not-allowed;
    transform: none;
}

#hud-wrapper {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    align-items: flex-end;
    gap: 20px;
    pointer-events: none;
    z-index: 5;
    display: none;
}

#stats-panel {
    background: rgba(0, 0, 0, 0.85);
    border: 2px solid #555;
    border-radius: 8px;
    padding: 10px 15px;
    color: white;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.6);
    font-weight: bold;
    font-size: 14px;
    min-width: 150px;
    border-left: 4px solid #f1c40f;
}

.stat-line {
    margin-bottom: 5px;
    display: flex;
    justify-content: space-between;
}

.stat-line span.val-hp {
    color: #2ecc71;
}

.stat-line span.val-mp {
    color: #3498db;
}

.stat-line span.val-lv {
    color: #f1c40f;
    font-size: 16px;
}

.stat-bar-bg {
    width: 100%;
    height: 8px;
    background: #333;
    border-radius: 4px;
    overflow: hidden;
    margin-top: 8px;
    border: 1px solid #222;
}

#ui-exp-bar {
    height: 100%;
    background: #9b59b6;
    width: 0%;
    box-shadow: 0 0 5px #9b59b6;
    transition: width 0.2s ease-out;
}

#ui-skills {
    display: flex;
    gap: 10px;
}

.skill {
    width: 60px;
    height: 60px;
    background: rgba(0, 0, 0, 0.8);
    border: 2px solid #555;
    border-radius: 8px;
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    position: relative;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.5);
    pointer-events: auto;
    cursor: help;
}

.skill.ult {
    border-color: #3498db;
    box-shadow: 0 0 15px #3498db;
}

.cooldown-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    background: rgba(231, 76, 60, 0.7);
    height: 0%;
    transition: height 0.1s linear;
}

.skill-key {
    position: absolute;
    top: 2px;
    left: 4px;
    font-size: 12px;
    color: #f1c40f;
    font-weight: bold;
    z-index: 2;
}

.skill-mana {
    position: absolute;
    top: 2px;
    right: 4px;
    font-size: 10px;
    color: #3498db;
    font-weight: bold;
    z-index: 2;
}

.skill-name {
    font-size: 10px;
    z-index: 2;
    margin-top: 15px;
    text-align: center;
    line-height: 1.1;
}

#buffs-container {
    display: flex;
    gap: 8px;
}

.buff-icon {
    width: 40px;
    height: 40px;
    background: #2c3e50;
    border: 2px solid #fff;
    border-radius: 5px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 9px;
    font-weight: bold;
    color: white;
    overflow: hidden;
    display: none;
}

.buff-sweep {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: conic-gradient(rgba(0, 0, 0, 0.8) 0%, transparent 0%);
    pointer-events: none;
}

.buff-text {
    z-index: 2;
    text-align: center;
    line-height: 1.2;
}

#minimap-container {
    position: absolute;
    top: 20px;
    right: 20px;
    width: 300px;
    height: 62.5px;
    background: rgba(0, 0, 0, 0.5);
    border: 2px solid #f39c12;
    z-index: 5;
    display: none;
}

#clone-counter {
    position: absolute;
    bottom: 100px;
    left: 50%;
    transform: translateX(-50%);
    color: #f1c40f;
    font-weight: bold;
    font-size: 18px;
    text-shadow: 0 0 8px #000;
    display: none;
    z-index: 5;
}

#damage-vignette {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    box-shadow: inset 0 0 100px rgba(255, 0, 0, 0);
    transition: box-shadow 0.2s;
    pointer-events: none;
    z-index: 4;
}

#game-over {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.85);
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 30;
}

#level-clear-notice {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #2ecc71;
    font-size: 80px;
    font-weight: bold;
    text-shadow: 0 0 30px #000;
    display: none;
    z-index: 40;
    pointer-events: none;
    text-align: center;
}

#skill-tooltip {
    position: absolute;
    background: rgba(0, 0, 0, 0.9);
    border: 1px solid #f39c12;
    border-radius: 8px;
    padding: 12px;
    color: #fff;
    font-size: 13px;
    pointer-events: none;
    display: none;
    z-index: 100;
    width: 250px;
    text-align: left;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.8);
    line-height: 1.5;
}

.tooltip-title {
    color: #f1c40f;
    font-weight: bold;
    font-size: 16px;
    margin-bottom: 5px;
    border-bottom: 1px solid #555;
    padding-bottom: 5px;
    text-transform: uppercase;
}

.tooltip-mana {
    color: #3498db;
    font-size: 12px;
    font-weight: bold;
}

.tooltip-cd {
    color: #e74c3c;
    font-size: 12px;
    margin-bottom: 8px;
    font-weight: bold;
}

.mode-btn {
    padding: 10px 25px;
    font-size: 16px;
    font-weight: bold;
    background: #222;
    color: #aaa;
    border: 2px solid #555;
    border-radius: 20px;
    cursor: pointer;
    margin: 0 10px 20px 10px;
    transition: 0.3s;
}

.mode-btn.active {
    background: #c0392b;
    color: #fff;
    border-color: #e74c3c;
    box-shadow: 0 0 15px #e74c3c;
}

#augment-screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.9);
    z-index: 60;
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(5px);
}

#augment-screen h1 {
    color: #f1c40f;
    font-size: 50px;
    text-shadow: 0 0 20px #e67e22;
    margin-bottom: 40px;
}

#augment-container {
    display: flex;
    gap: 30px;
}

.aug-card {
    width: 250px;
    height: 380px;
    background: linear-gradient(180deg, #2c3e50, #1a252c);
    border: 3px solid #f1c40f;
    border-radius: 15px;
    cursor: pointer;
    transition: 0.3s;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px;
    box-sizing: border-box;
}

.aug-card:hover {
    transform: translateY(-15px) scale(1.05);
    box-shadow: 0 15px 30px rgba(241, 196, 15, 0.5);
    border-color: #fff;
}

.aug-icon {
    font-size: 60px;
    margin-bottom: 20px;
}

.aug-name {
    color: #f1c40f;
    font-size: 24px;
    font-weight: bold;
    margin-bottom: 15px;
    text-align: center;
}

.aug-desc {
    color: #bdc3c7;
    font-size: 16px;
    text-align: center;
    line-height: 1.4;
}

#settings-btn {
    position: absolute;
    top: 20px;
    left: 20px;
    z-index: 50;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    border: 2px solid #f39c12;
    padding: 10px 15px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: bold;
    display: none;
    transition: 0.3s;
}

#settings-btn:hover {
    background: #f39c12;
    color: #000;
}

#settings-modal {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.85);
    z-index: 100;
    display: none;
    justify-content: center;
    align-items: center;
    backdrop-filter: blur(5px);
}

.settings-content {
    background: #222;
    border: 3px solid #f1c40f;
    padding: 30px;
    border-radius: 15px;
    color: white;
    width: 350px;
    box-shadow: 0 0 20px #e67e22;
}

.setting-row {
    margin: 20px 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 18px;
}

.key-btn {
    padding: 8px 20px;
    background: #333;
    color: #f1c40f;
    font-size: 16px;
    border: 2px solid #f1c40f;
    cursor: pointer;
    border-radius: 5px;
    font-weight: bold;
}

.key-btn:hover {
    background: #f1c40f;
    color: #000;
}

.switch {
    position: relative;
    display: inline-block;
    width: 50px;
    height: 28px;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #555;
    transition: .4s;
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 16px;
    width: 16px;
    left: 6px;
    bottom: 6px;
    background-color: white;
    transition: .4s;
    border-radius: 50%;
}

input:checked+.slider {
    background-color: #2ecc71;
}

input:checked+.slider:before {
    transform: translateX(22px);
}

/* --- PHẦN 1: STYLE TIÊU ĐỀ MỚI --- */
.game-title {
    font-size: 85px !important;
    margin-bottom: 20px;
    font-weight: 900;
    text-transform: uppercase;
    /* Hiệu ứng chữ Gradient */
    background: linear-gradient(180deg, #ff9f43 0%, #ff6b6b 100%);
    background-clip: text;
    -webkit-background-clip: text;
    color: transparent;
    -webkit-text-fill-color: transparent;
    /* Đổ bóng cho chữ nổi bật trên nền vũ trụ */
    filter: drop-shadow(0 0 15px rgba(255, 107, 107, 0.6));
}

/* --- TIÊU ĐỀ BANG BANG 3 RỰC RỠ --- */
.game-title {
    font-size: 85px !important;
    font-weight: 900;
    margin-bottom: 25px;
    text-transform: uppercase;
    /* Tạo hiệu ứng chữ Gradient Cam-Đỏ rực cháy */
    background: linear-gradient(180deg, #ff9f43 0%, #ff6b6b 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    color: transparent;
    /* Đổ bóng hào quang */
    filter: drop-shadow(0 0 15px rgba(255, 107, 107, 0.8));
}

/* --- KHUNG CHỌN CHẾ ĐỘ CĂN GIỮA TUYỆT ĐỐI --- */
#game-mode-selector {
    display: flex;
    flex-direction: column;
    align-items: center; /* Căn giữa nhãn và hàng nút bấm */
    background: rgba(0, 0, 0, 0.8); /* Nền đen mờ sang trọng */
    padding: 25px 45px;
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    margin: 20px 0;
    width: fit-content; /* Khung chỉ rộng vừa đủ nội dung */
}

.mode-label {
    color: #888;
    font-size: 14px;
    letter-spacing: 3px;
    margin-bottom: 20px;
    text-transform: uppercase;
}

.mode-buttons-row {
    display: flex;
    gap: 15px;
    justify-content: center; /* Đảm bảo các nút bấm nằm giữa hàng */
}

/* --- PHONG CÁCH NÚT BẤM CHUYÊN NGHIỆP --- */
.mode-btn {
    padding: 12px 25px;
    font-size: 16px;
    font-weight: bold;
    border-radius: 8px;
    border: 2px solid #444;
    background: #222;
    color: #fff;
    cursor: pointer;
    transition: 0.3s;
}

/* Màu sắc riêng biệt khi được chọn (Active) */
#btn-story.active { 
    background: #3498db !important; 
    border-color: #3498db; 
    box-shadow: 0 0 20px rgba(52, 152, 219, 0.6); 
}
#btn-survival.active { 
    background: #e74c3c !important; 
    border-color: #e74c3c; 
    box-shadow: 0 0 20px rgba(231, 76, 60, 0.6); 
}
#btn-practice.active { 
    background: #2ecc71 !important; 
    border-color: #2ecc71; 
    box-shadow: 0 0 20px rgba(46, 204, 113, 0.6); 
}

.mode-btn:hover:not(.active) {
    transform: translateY(-3px);
    border-color: #fff;
}