/* CSS Variables cho phong cách Tối giản & Chuyên nghiệp */
:root {
    --bg-color: #ffffff;
    --bg-alt: #f8fafc;
    --text-primary: #1e293b;
    --text-secondary: #475569;
    --primary-color: #0f172a;
    --accent-color: #3b82f6;
    --border-color: #e2e8f0;
    --radius: 8px;
    --transition: all 0.3s ease;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

/* Reset & Global */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Inter', sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-color);
    line-height: 1.6;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 0.5em;
    color: var(--primary-color);
}

a {
    text-decoration: none;
    color: var(--accent-color);
    transition: var(--transition);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

ul {
    list-style: none;
}

/* Container */
.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

.section-bg {
    background-color: var(--bg-alt);
}

section {
    padding: 5rem 0;
}

.section-title {
    font-size: 2rem;
    text-align: center;
    margin-bottom: 1rem;
    position: relative;
    padding-bottom: 1rem;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background-color: var(--primary-color);
    border-radius: 2px;
}

.section-subtitle {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius);
    font-weight: 500;
    cursor: pointer;
    text-align: center;
    transition: var(--transition);
    border: 2px solid transparent;
}

.btn-primary {
    background-color: var(--primary-color);
    color: #fff;
}
.btn-primary:hover {
    background-color: #1e293b;
    color: #fff;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background-color: var(--bg-alt);
    color: var(--primary-color);
    border-color: var(--border-color);
}
.btn-secondary:hover {
    background-color: #e2e8f0;
    transform: translateY(-2px);
}

.btn-outline {
    border: 1px solid var(--border-color);
    color: var(--primary-color);
    padding: 0.5rem 1rem;
}
.btn-outline:hover {
    background-color: var(--primary-color);
    color: #fff;
}

/* Navigation */
.navbar {
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
}
.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
    letter-spacing: -0.5px;
}
.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}
.nav-links a:not(.btn) {
    color: var(--text-secondary);
    font-weight: 500;
}
.nav-links a:not(.btn):hover {
    color: var(--primary-color);
}

/* Hero Section */
.hero-section {
    position: relative;
    background-color: #020617; /* Slate 950 */
    color: #fff;
    overflow: hidden;
}
.interactive-bg {
    display: none; /* Removed */
}
#network-canvas,
#network-canvas-portfolio {
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    z-index: 0;
}

.hero {
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: calc(100vh - 80px); /* 80px is approx nav height */
    padding-top: 3rem;
    padding-bottom: 3rem;
    position: relative;
    z-index: 1;
}
.hero-content {
    flex: 1;
    max-width: 600px;
    animation: fadeInUp 1s ease-out forwards;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 2.5rem;
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.3);
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}
.hero .greeting {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.125rem;
    margin-bottom: 0.5rem;
    font-weight: 500;
}
.hero .name {
    font-size: 3.5rem;
    font-weight: 700;
    letter-spacing: -1px;
    margin-bottom: 0.5rem;
    color: #fff;
}
.hero .title {
    font-size: 1.5rem;
    color: #93c5fd;
    font-weight: 500;
    margin-bottom: 1.5rem;
}
.hero .summary {
    font-size: 1.125rem;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 2.5rem;
}
.hero-actions {
    display: flex;
    gap: 1rem;
}
.hero-actions .btn-secondary {
    background-color: rgba(255, 255, 255, 0.1);
    color: #fff;
    border-color: rgba(255, 255, 255, 0.3);
}
.hero-actions .btn-secondary:hover {
    background-color: rgba(255, 255, 255, 0.2);
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: flex-end;
}
.image-wrapper {
    width: 350px;
    height: 350px;
    border-radius: 50%;
    padding: 6px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.3) 0%, rgba(226, 232, 240, 0.1) 100%);
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}
.image-wrapper::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(
        circle 120px at var(--x, 50%) var(--y, 50%),
        rgba(255, 255, 255, 0.9),
        transparent 100%
    );
    opacity: 0;
    transition: opacity 0.3s ease;
}
.image-wrapper:hover::before {
    opacity: 1;
}

.profile-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 50%;
    border: 4px solid #020617;
    position: relative;
    z-index: 1;
}

/* About Section */
.about-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 4rem;
    margin-top: 3rem;
}
.about-text p {
    margin-bottom: 1.5rem;
    font-size: 1.05rem;
    color: var(--text-secondary);
}
.about-text strong {
    color: var(--text-primary);
}
.about-highlights {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}
.highlight-item {
    background-color: var(--bg-color);
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    transition: var(--transition);
}
.highlight-item:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}
.highlight-item i {
    font-size: 1.5rem;
    color: var(--accent-color);
    margin-bottom: 1rem;
}
.highlight-item h4 {
    margin-bottom: 0.5rem;
}
.highlight-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Portfolio / Audio Section */
.info-alert {
    background-color: #eff6ff;
    border-left: 4px solid var(--accent-color);
    padding: 1rem 1.5rem;
    border-radius: 0 var(--radius) var(--radius) 0;
    margin-bottom: 3rem;
    display: flex;
    gap: 1rem;
    align-items: flex-start;
}
.info-alert i {
    color: var(--accent-color);
    margin-top: 0.2rem;
}
.info-alert span {
    font-size: 0.9rem;
    color: #1e3a8a;
}
.info-alert code {
    background-color: #dbeafe;
    padding: 0.1rem 0.3rem;
    border-radius: 4px;
    font-family: monospace;
}

.portfolio {
    position: relative;
    overflow: hidden;
}
.relative-z {
    position: relative;
    z-index: 1;
}

.audio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
}
.audio-card {
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 2rem;
    background-color: var(--bg-color);
    transition: var(--transition);
}
.audio-card:hover {
    box-shadow: 0 10px 20px rgba(0,0,0,0.08);
    border-color: var(--accent-color);
    transform: translateY(-5px);
}
.audio-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}
.audio-tag {
    background-color: #f1f5f9;
    color: var(--text-secondary);
    font-size: 0.8rem;
    font-weight: 600;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
}
.audio-card h4 {
    font-size: 1.25rem;
    margin-bottom: 0;
}
.audio-desc {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
}
.audio-player audio {
    width: 100%;
    outline: none;
}
/* Tuỳ biến style của audio player cơ bản (tuỳ thuộc vào browser) */
audio::-webkit-media-controls-panel {
    background-color: #f8fafc;
}

.btn-script {
    background: none;
    border: none;
    color: var(--accent-color);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    margin-top: 1rem;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0;
    transition: var(--transition);
}
.btn-script:hover {
    color: var(--primary-color);
}

.script-content {
    display: none;
    margin-top: 1rem;
    padding: 1rem;
    background-color: #f8fafc;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-size: 0.9rem;
    color: var(--text-secondary);
}
.script-content strong {
    color: var(--text-primary);
    display: block;
    margin-top: 0.5rem;
    margin-bottom: 0.25rem;
}
.script-content strong:first-child {
    margin-top: 0;
}

/* Skills & Equipment Section */
.skills-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    margin-top: 3rem;
}
.col-title {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}
.col-title i {
    color: var(--accent-color);
}
.skill-list li {
    margin-bottom: 1.5rem;
    padding-left: 1.5rem;
    position: relative;
    color: var(--text-secondary);
}
.skill-list li::before {
    content: '•';
    color: var(--accent-color);
    font-weight: bold;
    font-size: 1.5rem;
    position: absolute;
    left: 0;
    top: -4px;
}
.skill-list strong {
    color: var(--text-primary);
    display: block;
    margin-bottom: 0.25rem;
}

.equip-card {
    display: flex;
    gap: 1.5rem;
    margin-bottom: 2rem;
    padding: 1.5rem;
    background-color: var(--bg-color);
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
}
.equip-icon {
    width: 50px;
    height: 50px;
    background-color: #f1f5f9;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--primary-color);
    flex-shrink: 0;
}
.equip-info h5 {
    font-size: 1.1rem;
    margin-bottom: 0.25rem;
}
.equip-info p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Contact Section */
.contact-box {
    background-color: var(--primary-color);
    color: #fff;
    padding: 4rem;
    border-radius: 16px;
    text-align: center;
}
.contact-box .section-title {
    color: #fff;
}
.contact-box .section-title::after {
    background-color: var(--accent-color);
}
.contact-box p {
    color: #cbd5e1;
    font-size: 1.1rem;
    margin-bottom: 3rem;
}
.contact-links {
    display: flex;
    justify-content: center;
    gap: 3rem;
    flex-wrap: wrap;
}
.contact-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: #fff;
    font-size: 1.1rem;
    font-weight: 500;
}
.contact-item:hover {
    color: var(--accent-color);
    transform: translateY(-2px);
}
.contact-item i {
    font-size: 1.5rem;
}

/* Footer */
.footer {
    text-align: center;
    padding: 2rem 0;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 992px) {
    .hero {
        flex-direction: column;
        text-align: center;
        padding-top: 4rem;
    }
    .hero-image {
        margin-top: 3rem;
        justify-content: center;
    }
    .hero-actions {
        justify-content: center;
    }
    .about-grid, .skills-wrapper {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none; /* Trong thực tế cần có hamburger menu, nhưng với bản tối giản ta có thể ẩn tuỳ chọn trên mobile để giữ thiết kế đơn giản hoặc đổi layout */
    }
    .hero .name {
        font-size: 2.5rem;
    }
    .hero .title {
        font-size: 1.2rem;
    }
    .audio-grid {
        grid-template-columns: 1fr;
    }
    .contact-box {
        padding: 3rem 1.5rem;
    }
    .contact-links {
        flex-direction: column;
        gap: 1.5rem;
        align-items: center;
    }
}