:root {
    /* Dark Mode Defaults */
    --bg-color: #0b0f19;
    --surface-color: #141b2d;
    --text-primary: #e2e8f0;
    --text-secondary: #94a3b8;
    --accent-color: #00f0ff;
    --accent-hover: #00c3ff;
    --card-bg: #1e293b;
    --border-color: #334155;
    --nav-bg: rgba(11, 15, 25, 0.9);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    --shadow-hover: 0 10px 40px rgba(0, 240, 255, 0.2);
    --transition: all 0.3s ease;
}

body.light-mode {
    --bg-color: #f8fafc;
    --surface-color: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --accent-color: #0284c7;
    --accent-hover: #0369a1;
    --card-bg: #ffffff;
    --border-color: #e2e8f0;
    --nav-bg: rgba(248, 250, 252, 0.9);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 10px 40px rgba(2, 132, 199, 0.2);
}

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

html {
    scroll-behavior: smooth;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.section {
    padding: 100px 0;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    text-align: center;
    position: relative;
    display: inline-block;
    left: 50%;
    transform: translateX(-50%);
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60%;
    height: 4px;
    background-color: var(--accent-color);
    border-radius: 2px;
}

/* Cards */
.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
    border-color: var(--accent-color);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-size: 1rem;
    text-align: center;
}

.primary-btn {
    background-color: var(--accent-color);
    color: #000;
}

.primary-btn:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 240, 255, 0.4);
}

body.light-mode .primary-btn {
    color: #fff;
}

body.light-mode .primary-btn:hover {
    box-shadow: 0 5px 15px rgba(2, 132, 199, 0.4);
}

.secondary-btn {
    background-color: transparent;
    color: var(--accent-color);
    border: 2px solid var(--accent-color);
}

.secondary-btn:hover {
    background-color: rgba(0, 240, 255, 0.1);
    transform: translateY(-2px);
}

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    padding: 1rem 5%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: var(--nav-bg);
    backdrop-filter: blur(10px);
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.logo {
    font-size: 1.8rem;
    font-weight: 800;
    color: var(--accent-color);
}

.nav-links {
    display: flex;
    list-style: none;
    align-items: center;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
}

.nav-links a:hover {
    color: var(--accent-color);
}

.theme-btn {
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.2rem;
    cursor: pointer;
    transition: var(--transition);
}

.theme-btn:hover {
    color: var(--accent-color);
}

.hamburger {
    display: none;
    cursor: pointer;
}

.hamburger .bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 5px auto;
    background-color: var(--text-primary);
    transition: all 0.3s ease-in-out;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 80px 0 0 0;
    background: radial-gradient(circle at center, var(--surface-color) 0%, var(--bg-color) 100%);
}

.hero-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 3rem;
    width: 100%;
}

.hero-content {
    flex: 1.2;
    text-align: left;
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    position: relative;
}

.hero-image::before {
    content: '';
    position: absolute;
    width: 320px;
    height: 440px;
    background: #ffffff; /* تغيير الهالة لبيضاء لتبدو فورمال ومهنية اكثر */
    border-radius: 12px;
    filter: blur(80px);
    opacity: 0.1; /* هالة هادئة جدا */
    z-index: -1;
    animation: pulseGlow 4s infinite alternate;
}

@keyframes pulseGlow {
    0% { opacity: 0.05; transform: scale(0.95); }
    100% { opacity: 0.15; transform: scale(1.05); }
}

.hero-img-wrapper {
    width: 360px;
    height: 480px;
    border-radius: 16px;
    border: 3px solid var(--accent-color);
    padding: 0;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5), 0 0 30px rgba(0, 240, 255, 0.15);
    position: relative;
    z-index: 1;
    overflow: hidden;
    background: var(--surface-color);
}

body.dark-mode .hero-img-wrapper {
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.7), 0 0 40px rgba(0, 240, 255, 0.1);
}

.hero-img-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center top;
    /* HD rendering - أفضل جودة عرض ممكنة في المتصفح */
    image-rendering: -webkit-optimize-contrast;
    image-rendering: crisp-edges;
    -ms-interpolation-mode: bicubic;
    filter: contrast(1.05) brightness(1.02) saturate(1.08);
    display: block;
    background-color: transparent;
    /* منع تغبيش الصورة عند التصغير */
    backface-visibility: hidden;
    transform: translateZ(0);
    will-change: transform;
}

.greeting {
    font-size: 1.2rem;
    color: var(--accent-color);
    margin-bottom: 1rem;
    font-weight: 600;
    letter-spacing: 2px;
}

.name {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.title {
    font-size: 1.5rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-weight: 400;
}

.tagline {
    font-size: 1.1rem;
    margin: 0 0 2.5rem 0;
    font-style: italic;
    color: var(--text-secondary);
    line-height: 1.8;
}

.cta-buttons {
    display: flex;
    gap: 1.5rem;
    justify-content: flex-start;
}

/* About Section */
.about-content {
    display: flex;
    gap: 4rem;
    align-items: center;
}

.profile-img {
    flex: 1;
    display: flex;
    justify-content: center;
}

.img-placeholder {
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--surface-color), var(--bg-color));
    border: 4px solid var(--accent-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 8rem;
    color: var(--accent-color);
    box-shadow: var(--shadow-hover);
}

.about-text {
    flex: 2;
    font-size: 1.1rem;
}

.career-objective {
    margin-top: 2rem;
    padding-left: 1.5rem;
    border-left: 4px solid var(--accent-color);
}

.career-objective h3 {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

/* Skills Section */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.skill-category h3 {
    margin-bottom: 1rem;
    color: var(--accent-color);
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Experience Section */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::after {
    content: '';
    position: absolute;
    width: 2px;
    background-color: var(--border-color);
    top: 0;
    bottom: 0;
    left: 20px;
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
    padding-left: 60px;
}

.timeline-dot {
    position: absolute;
    width: 20px;
    height: 20px;
    background-color: var(--accent-color);
    border-radius: 50%;
    left: 11px;
    top: 5px;
    z-index: 1;
    box-shadow: 0 0 10px var(--accent-color);
}

.timeline-date {
    color: var(--accent-color);
    font-weight: 600;
    margin-bottom: 1rem;
}

.timeline-content ul {
    margin-top: 1rem;
    padding-left: 1.5rem;
    color: var(--text-secondary);
}

.timeline-content li {
    margin-bottom: 0.5rem;
}

.skills-list {
    list-style: none;
    margin-top: 1rem;
}

.skills-list li {
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 15px;
    font-size: 1.1rem;
}

.skills-list i {
    color: var(--accent-color);
    font-size: 1.2rem;
}

.mt-4 {
    margin-top: 2rem;
}

/* Projects Section */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.project-icon {
    font-size: 3rem;
    color: var(--accent-color);
    margin-bottom: 1.5rem;
}

.project-card h3 {
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.project-card p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

/* Services Section */
.service-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    text-align: center;
}

.service-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem 2rem;
}

.service-card i {
    font-size: 3rem;
    color: var(--accent-color);
    margin-bottom: 1.5rem;
}

/* Certifications Section */
.cert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.cert-card {
    display: flex;
    align-items: center;
    gap: 20px;
}

.cert-icon {
    font-size: 2.5rem;
    color: var(--accent-color);
}

.cert-card h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.cert-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Contact Section */
.contact-container {
    display: flex;
    gap: 3rem;
}

.contact-info, .contact-form {
    flex: 1;
}

.contact-info p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 15px;
}

.contact-info i {
    color: var(--accent-color);
    font-size: 1.3rem;
}

.social-links {
    margin-top: 3rem;
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.social-btn {
    background-color: var(--surface-color);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 10px;
}

.social-btn:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    background-color: var(--surface-color);
    color: var(--text-primary);
    font-family: inherit;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 10px rgba(0, 240, 255, 0.2);
}

.submit-btn {
    width: 100%;
}

/* Footer */
footer {
    background-color: var(--surface-color);
    padding: 3rem 0;
    text-align: center;
    position: relative;
    border-top: 1px solid var(--border-color);
}

.back-to-top {
    position: absolute;
    top: -25px;
    left: 50%;
    transform: translateX(-50%);
    width: 50px;
    height: 50px;
    background-color: var(--accent-color);
    color: #000;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    font-size: 1.5rem;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.back-to-top:hover {
    transform: translate(-50%, -5px);
    background-color: var(--accent-hover);
}

body.light-mode .back-to-top {
    color: #fff;
}

footer p {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

/* Animations & Utilities */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-in.appear {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive */
@media screen and (max-width: 992px) {
    .hero-container {
        flex-direction: column-reverse;
        text-align: center;
        padding-top: 6rem;
        gap: 2rem;
    }
    
    .hero-content {
        text-align: center;
        display: flex;
        flex-direction: column;
        align-items: center;
    }
    
    .cta-buttons {
        justify-content: center;
    }

    .name {
        font-size: 2.8rem;
    }
    
    .about-content {
        flex-direction: column;
    }
    
    .contact-container {
        flex-direction: column;
    }
}

@media screen and (max-width: 768px) {
    .nav-links {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--nav-bg);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
        backdrop-filter: blur(10px);
    }

    .nav-links.active {
        left: 0;
    }

    .hamburger {
        display: block;
    }

    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }
    
    .name {
        font-size: 2.2rem;
    }
    
    .title {
        font-size: 1.3rem;
    }
    
    .hero-img-wrapper {
        width: 280px;
        height: 380px;
    }

    .hero-image::before {
        width: 260px;
        height: 360px;
    }
    
    .cta-buttons {
        flex-direction: column;
        width: 100%;
    }
    
    .cta-buttons .btn {
        width: 100%;
    }
}