/* Design System & Variables */
:root {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-primary: #38bdf8;
    --accent-secondary: #818cf8;
    --accent-glow: rgba(56, 189, 248, 0.5);
    --font-sans: 'Inter', sans-serif;
    --font-heading: 'Outfit', sans-serif;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 2rem;
    --spacing-xl: 4rem;
    --transition-fast: 0.2s ease;
    --transition-smooth: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    --header-bg: rgba(15, 23, 42, 0.9);
    --skill-bg: rgba(30, 41, 59, 0.5);
    --section-bg: rgba(30, 41, 59, 0.3);
}

.light-mode {
    --bg-primary: #f8fafc;
    --bg-secondary: #e2e8f0;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --accent-primary: #0284c7;
    --accent-secondary: #6366f1;
    --accent-glow: rgba(2, 132, 199, 0.5);
    --header-bg: rgba(248, 250, 252, 0.9);
    --skill-bg: rgba(226, 232, 240, 0.8);
    --section-bg: rgba(226, 232, 240, 0.5);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.section {
    padding: 80px 0;
}

.section-title {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    margin-bottom: var(--spacing-xl);
    text-align: center;
    background: linear-gradient(to right, var(--accent-primary), var(--accent-secondary));
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
}

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

.btn-primary:hover {
    background-color: var(--accent-secondary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--accent-glow);
}

.btn-secondary {
    border: 2px solid var(--accent-primary);
    color: var(--accent-primary);
    margin-left: var(--spacing-md);
}

.btn-secondary:hover {
    background-color: rgba(56, 189, 248, 0.1);
}

.header {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: var(--header-bg);
    backdrop-filter: blur(10px);
    z-index: 1000;
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
}

.nav-list {
    display: flex;
    gap: var(--spacing-lg);
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
}

.nav-link:hover {
    color: var(--accent-primary);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
}

.theme-toggle {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    margin-left: var(--spacing-lg);
}

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

.hero {
    padding-top: 160px;
    padding-bottom: 100px;
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    background: var(--bg-primary) url('hero-bg-dark.jpg') center/cover no-repeat;
    overflow: hidden;
}

.light-mode .hero {
    background-image: url('hero-bg-light.png');
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to right, rgba(15, 23, 42, 0.85) 0%, rgba(15, 23, 42, 0.4) 50%, rgba(15, 23, 42, 0.7) 100%);
    z-index: 1;
}

.light-mode .hero::before {
    background: linear-gradient(to right, rgba(248, 250, 252, 0.85) 0%, rgba(248, 250, 252, 0.4) 50%, rgba(248, 250, 252, 0.7) 100%);
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
    align-items: center;
    position: relative;
    z-index: 2;
}

.company-badge {
    display: inline-block;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: var(--bg-primary);
    padding: 8px 20px;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    box-shadow: 0 4px 15px rgba(56, 189, 248, 0.3);
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 3.5rem;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
}

.highlight {
    color: var(--accent-primary);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
    max-width: 500px;
}

.hero-cta {
    display: flex;
    gap: 0;
    flex-wrap: wrap;
}

.profile-img {
    width: 350px;
    height: 350px;
    object-fit: cover;
    border-radius: 50%;
    border: 4px solid var(--accent-primary);
    box-shadow: 0 0 30px rgba(56, 189, 248, 0.3);
    margin: 0 auto;
    display: block;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {

    0%,
    100% {
        transform: translateY(0px);
    }

    50% {
        transform: translateY(-20px);
    }
}

.summary-section {
    background-color: rgba(56, 189, 248, 0.05);
    border-left: 4px solid var(--accent-primary);
    padding: var(--spacing-lg) 0;
}

.summary-container {
    max-width: 900px;
}

.summary-text {
    font-size: 1.15rem;
    line-height: 1.8;
    color: var(--text-secondary);
    text-align: center;
}

.summary-text strong {
    color: var(--accent-primary);
    font-weight: 600;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
    align-items: start;
}

.about-text p {
    margin-bottom: var(--spacing-md);
    color: var(--text-secondary);
}

.skills-wrapper {
    display: flex;
    flex-direction: column;
}

.skills-category {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    display: block;
    width: 100%;
}

.skills-grid {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    align-content: flex-start;
}

.skill-item {
    background-color: var(--skill-bg);
    padding: 10px 20px;
    border-radius: 50px;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--accent-primary);
    border: 1px solid rgba(56, 189, 248, 0.2);
    transition: var(--transition-fast);
    cursor: default;
}

.skill-item:hover {
    background-color: rgba(56, 189, 248, 0.1);
    border-color: var(--accent-primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(56, 189, 248, 0.1);
}

/* 3D CERTIFICATION CARDS - 4 COLUMN RESPONSIVE LAYOUT */
.certifications {
    background-color: var(--section-bg);
    perspective: 1200px;
}

.cert-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.cert-card {
    background: linear-gradient(145deg, #1e293b 0%, #0f172a 100%);
    padding: 2.5rem 2rem;
    border-radius: 20px;
    text-align: center;
    border: 1px solid rgba(56, 189, 248, 0.2);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: relative;
    transform-style: preserve-3d;
    min-height: 280px;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    box-shadow:
        0 2px 4px rgba(0, 0, 0, 0.1),
        0 4px 8px rgba(0, 0, 0, 0.15),
        0 8px 16px rgba(0, 0, 0, 0.2),
        0 16px 32px rgba(0, 0, 0, 0.25),
        inset 0 -2px 4px rgba(0, 0, 0, 0.3),
        inset 0 2px 4px rgba(255, 255, 255, 0.05);
}

.cert-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 5px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    border-radius: 20px 20px 0 0;
    box-shadow: 0 2px 10px rgba(56, 189, 248, 0.5);
}

.cert-card:hover {
    transform: translateY(-15px) scale(1.02);
    border-color: rgba(56, 189, 248, 0.5);
    box-shadow:
        0 5px 10px rgba(0, 0, 0, 0.15),
        0 10px 20px rgba(0, 0, 0, 0.2),
        0 20px 40px rgba(0, 0, 0, 0.3),
        0 30px 60px rgba(0, 0, 0, 0.35),
        0 0 40px rgba(56, 189, 248, 0.3),
        inset 0 -2px 4px rgba(0, 0, 0, 0.3),
        inset 0 2px 6px rgba(255, 255, 255, 0.08);
}

.light-mode .cert-card {
    background: linear-gradient(145deg, #ffffff 0%, #f1f5f9 100%);
    border: 1px solid rgba(2, 132, 199, 0.25);
    box-shadow:
        0 2px 4px rgba(0, 0, 0, 0.05),
        0 4px 8px rgba(0, 0, 0, 0.07),
        0 8px 16px rgba(0, 0, 0, 0.09),
        0 16px 32px rgba(0, 0, 0, 0.11),
        inset 0 -2px 4px rgba(0, 0, 0, 0.08),
        inset 0 2px 4px rgba(255, 255, 255, 0.8);
}

.light-mode .cert-card:hover {
    transform: translateY(-15px) scale(1.02);
    border-color: rgba(2, 132, 199, 0.5);
    box-shadow:
        0 5px 10px rgba(0, 0, 0, 0.08),
        0 10px 20px rgba(0, 0, 0, 0.1),
        0 20px 40px rgba(0, 0, 0, 0.12),
        0 30px 60px rgba(0, 0, 0, 0.14),
        0 0 40px rgba(2, 132, 199, 0.2),
        inset 0 -2px 4px rgba(0, 0, 0, 0.08),
        inset 0 2px 6px rgba(255, 255, 255, 0.9);
}

.light-mode .cert-icon {
    filter: drop-shadow(0 4px 8px rgba(2, 132, 199, 0.3));
}

.cert-icon {
    font-size: 3.5rem;
    margin-bottom: 1.25rem;
    filter: drop-shadow(0 4px 8px rgba(56, 189, 248, 0.4));
}

.cert-title {
    font-family: var(--font-heading);
    font-size: 1.35rem;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
    line-height: 1.4;
}

.cert-desc {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.6;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.project-card {
    background-color: var(--bg-secondary);
    border-radius: 16px;
    overflow: hidden;
    transition: var(--transition-smooth);
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
    border-color: rgba(56, 189, 248, 0.3);
}

.project-info {
    padding: var(--spacing-lg);
}

.project-title {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
}

.project-desc {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    font-size: 0.95rem;
}

.project-links {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.link-item {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--accent-primary);
}

.link-item:hover {
    text-decoration: underline;
}

.contact-container {
    text-align: center;
    max-width: 700px;
}

.contact-text {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    font-size: 1.1rem;
    line-height: 1.7;
}

.contact-links {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-xl);
}

.contact-info {
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.contact-info p {
    margin: 0;
}

.footer {
    padding: var(--spacing-lg) 0;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    margin-top: var(--spacing-xl);
}

.footer-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.social-links {
    display: flex;
    gap: var(--spacing-md);
}

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

.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
    align-items: center;
    justify-content: center;
}

.modal-content {
    background-color: var(--bg-secondary);
    padding: 2rem;
    border-radius: 16px;
    max-width: 600px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    position: relative;
    border: 1px solid rgba(56, 189, 248, 0.2);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.close-modal {
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    font-size: 2rem;
    font-weight: bold;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition-fast);
}

.close-modal:hover {
    color: var(--accent-primary);
}

/* RESPONSIVE BREAKPOINTS */
@media (max-width: 1199px) and (min-width: 768px) {
    .cert-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
    }
}

@media (max-width: 768px) {
    .header-container {
        padding: 0 var(--spacing-md);
    }

    .nav-list {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 70%;
        background-color: rgba(15, 23, 42, 0.95);
        backdrop-filter: blur(10px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        transition: var(--transition-smooth);
        box-shadow: -10px 0 30px rgba(0, 0, 0, 0.5);
    }

    .nav-list.active {
        right: 0;
    }

    .nav-link {
        font-size: 1.5rem;
    }

    .mobile-menu-btn {
        display: block;
        z-index: 1001;
    }

    .mobile-menu-btn span {
        display: block;
        width: 25px;
        height: 3px;
        background-color: var(--text-primary);
        margin: 5px 0;
        transition: var(--transition-fast);
    }

    .mobile-menu-btn.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .mobile-menu-btn.active span:nth-child(2) {
        opacity: 0;
    }

    .mobile-menu-btn.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }

    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: var(--spacing-lg);
    }

    .hero-content {
        order: 2;
    }

    .hero-image {
        order: 1;
        max-width: 400px;
        margin: 0 auto;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        margin-left: auto;
        margin-right: auto;
    }

    /* Button Fix: Center alignment and consistent min-width */
    .hero-cta {
        justify-content: center;
        gap: var(--spacing-md);
    }

    .btn {
        min-width: 160px;
        text-align: center;
    }

    .about-content {
        grid-template-columns: 1fr;
    }

    .cert-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .footer-container {
        flex-direction: column;
        gap: var(--spacing-md);
    }
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background:
        radial-gradient(circle at 20% 30%, rgba(56, 189, 248, 0.08) 0%, transparent 40%),
        radial-gradient(circle at 80% 70%, rgba(129, 140, 248, 0.06) 0%, transparent 40%),
        radial-gradient(circle at 50% 50%, rgba(56, 189, 248, 0.04) 0%, transparent 60%);
    animation: backgroundShift 15s ease-in-out infinite;
    z-index: -1;
    pointer-events: none;
}

@keyframes backgroundShift {

    0%,
    100% {
        opacity: 1;
        transform: translateY(0);
    }

    50% {
        opacity: 0.7;
        transform: translateY(-20px);
    }
}