:root {
    --neon-red: #ff1a1a;
    --neon-cyan: #00ffff;
    --neon-yellow: #ffff33;
    --neon-purple: #cc00ff;
    --dark-bg: rgba(10, 10, 25, 0.92);
    --glow: 0 0 12px;
    --transition: all 0.3s ease;
}

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

body {
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: flex-start; /* Thay align-items: center thành flex-start để nội dung bắt đầu từ trên */
    background: linear-gradient(145deg, #0a0a1f, #1f1f3d);
    font-family: 'Roboto Mono', monospace;
    color: #fff;
    overflow-x: hidden; /* Chỉ ẩn cuộn ngang */
    overflow-y: auto; /* Cho phép cuộn dọc */
    position: relative;
    padding: 20px 0; /* Thêm padding để nội dung không sát cạnh trên/dưới */
}

body::before {
    content: '';
    position: fixed; /* Đổi thành fixed để nền không cuộn theo */
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    animation: bgMove 10s linear infinite;
    opacity: 0.12;
    z-index: -1;
    filter: blur(3px);
}

@keyframes bgMove {
    0% { background-position: 0 0; }
    100% { background-position: -1920px 0; }
}

.container {
    width: 90%;
    max-width: 540px;
    background: var(--dark-bg);
    border-radius: 30px;
    padding: 30px;
    box-shadow: var(--glow) var(--neon-purple), inset 0 0 10px var(--neon-cyan);
    backdrop-filter: blur(12px);
    border: 1px solid var(--neon-cyan);
    position: relative;
    animation: fadeInContainer 1.2s ease-in-out;
}

@keyframes fadeInContainer {
    0% { opacity: 0; transform: translateY(30px); }
    100% { opacity: 1; transform: translateY(0); }
}

.header {
    position: relative;
    height: 220px;
    background: linear-gradient(180deg, rgba(204, 0, 255, 0.25), transparent);
    border-radius: 25px 25px 0 0;
    overflow: visible;
}

.profile-pic {
    width: 160px;
    height: 160px;
    border-radius: 50%;
    border: 6px solid var(--neon-cyan);
    background: url('img/avatar.png') no-repeat center/contain; /* Giữ contain để hiển thị đầy đủ */
    position: absolute;
    bottom: -20px;
    left: 50%;
    transform: translateX(-50%);
    box-shadow: var(--glow) var(--neon-cyan), inset 0 0 15px var(--neon-purple);
    transition: transform 0.5s ease, box-shadow 0.5s ease;
    z-index: 1;
}

.profile-pic:hover {
    transform: translateX(-50%) scale(1.12);
    box-shadow: var(--glow) var(--neon-yellow), inset 0 0 18px var(--neon-red);
}

.neon-border {
    position: absolute;
    top: -2px;
    left: -2px;
    width: calc(100% + 4px);
    height: calc(100% + 4px);
    border: 2px solid var(--neon-purple);
    border-radius: 25px 25px 0 0;
    animation: neonPulse 2s infinite;
}

@keyframes neonPulse {
    0%, 100% { box-shadow: var(--glow) var(--neon-purple); }
    50% { box-shadow: var(--glow) var(--neon-cyan); }
}

h1.neon-text {
    margin: 150px 0 12px;
    font-size: 36px;
    font-family: 'Orbitron', sans-serif;
    font-weight: 700;
    text-transform: uppercase;
    animation: neonGlow 1.5s infinite alternate;
    letter-spacing: 4px;
    text-align: center;
}

h2.neon-text {
    font-size: 24px;
    font-family: 'Orbitron', sans-serif;
    margin: 25px 0;
    animation: neonGlow 1.5s infinite alternate;
    text-align: center;
}

@keyframes neonGlow {
    0% { color: var(--neon-red); text-shadow: var(--glow) var(--neon-red); }
    100% { color: var(--neon-yellow); text-shadow: var(--glow) var(--neon-yellow); }
}

.datetime {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
    font-size: 17px;
    color: var(--neon-cyan);
    text-shadow: var(--glow) var(--neon-cyan);
    margin: 12px 0;
}

.date {
    font-weight: 600;
    background: rgba(0, 255, 255, 0.1);
    padding: 4px 10px;
    border-radius: 6px;
}

.time {
    font-weight: 700;
    background: rgba(0, 255, 255, 0.15);
    padding: 4px 10px;
    border-radius: 6px;
    animation: blink 1s infinite;
}

@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

.intro, .bio {
    font-size: 14px;
    color: #e0e0e0;
    margin: 20px 0;
    padding: 0 25px;
    line-height: 1.7;
    text-align: center;
    animation: fadeInText 2s ease-in-out;
}

@keyframes fadeInText {
    0% { opacity: 0; transform: translateY(15px); }
    100% { opacity: 1; transform: translateY(0); }
}

.button-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 18px;
    padding: 25px;
}

.cyber-btn {
    padding: 14px;
    background: linear-gradient(45deg, var(--neon-cyan), var(--neon-purple));
    color: #fff;
    border-radius: 12px;
    text-decoration: none;
    font-family: 'Orbitron', sans-serif;
    font-weight: 600;
    text-transform: uppercase;
    border: 1px solid var(--neon-cyan);
    box-shadow: var(--glow) var(--neon-cyan);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    text-align: center;
}

.cyber-btn span {
    position: relative;
    z-index: 1;
}

.cyber-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    transition: left 0.6s ease;
}

.cyber-btn:hover::before {
    left: 100%;
}

.cyber-btn:hover {
    transform: translateY(-5px);
    box-shadow: var(--glow) var(--neon-yellow);
    background: linear-gradient(45deg, var(--neon-purple), var(--neon-red));
}

.nav-bar {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-around;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.9), rgba(0, 0, 0, 0.7));
    padding: 15px 20px;
    border-radius: 0 0 25px 25px;
    box-shadow: inset 0 0 15px var(--neon-purple);
    gap: 15px;
}

.nav-item {
    padding: 10px 15px;
    text-decoration: none;
    color: var(--neon-cyan);
    font-size: 14px;
    font-family: 'Orbitron', sans-serif;
    font-weight: 600;
    text-transform: uppercase;
    border-radius: 8px;
    transition: var(--transition);
    position: relative;
    background: rgba(0, 255, 255, 0.05);
    min-width: 100px;
    text-align: center;
}

.nav-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 1px solid var(--neon-cyan);
    border-radius: 8px;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.nav-item:hover::before {
    opacity: 1;
}

.nav-item:hover {
    color: var(--neon-yellow);
    text-shadow: var(--glow) var(--neon-yellow);
    background: rgba(255, 255, 51, 0.1);
    transform: translateY(-2px);
}

footer {
    margin-top: 25px;
    padding: 20px;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.8), rgba(0, 0, 0, 0.6));
    border-top: 1px solid var(--neon-cyan);
    border-radius: 0 0 25px 25px;
    text-align: center;
}