/* Base Styles and Variables */
:root {
    /* Color System */
    --primary-color: #0A6EBD;
    --primary-light: #2E97F2;
    --primary-dark: #064a80;
    
    --secondary-color: #35A29F;
    --secondary-light: #70d1ce;
    --secondary-dark: #297e7b;
    
    --accent-color: #FFA41B;
    --accent-light: #ffc268;
    --accent-dark: #e08600;
    
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    
    --neutral-100: #f8fafc;
    --neutral-200: #e2e8f0;
    --neutral-300: #cbd5e1;
    --neutral-400: #94a3b8;
    --neutral-500: #64748b;
    --neutral-600: #475569;
    --neutral-700: #334155;
    --neutral-800: #1e293b;
    --neutral-900: #0f172a;
    
    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    --font-size-base: 16px;
    --line-height-body: 1.5;
    --line-height-headings: 1.2;
    
    /* Spacing */
    --spacing-1: 8px;
    --spacing-2: 16px;
    --spacing-3: 24px;
    --spacing-4: 32px;
    --spacing-5: 48px;
    --spacing-6: 64px;
    
    /* Effects */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    
    --border-radius-sm: 4px;
    --border-radius-md: 8px;
    --border-radius-lg: 16px;
    
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Layout */
    --header-height: 70px;
    --container-max-width: 1200px;

    /* Theme colors (will change with dark mode) */
    --bg-primary: var(--neutral-100);
    --bg-secondary: white;
    --bg-tertiary: var(--neutral-200);
    --text-primary: var(--neutral-900);
    --text-secondary: var(--neutral-700);
    --text-tertiary: var(--neutral-500);
    --border-color: var(--neutral-300);
}

/* Dark Theme Colors */
.dark-theme {
    --bg-primary: var(--neutral-900);
    --bg-secondary: var(--neutral-800);
    --bg-tertiary: var(--neutral-700);
    --text-primary: var(--neutral-100);
    --text-secondary: var(--neutral-300);
    --text-tertiary: var(--neutral-400);
    --border-color: var(--neutral-700);

    color-scheme: dark;
}

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

/* Base Styles */
html {
    font-size: var(--font-size-base);
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    line-height: var(--line-height-body);
    color: var(--text-primary);
    background-color: var(--bg-primary);
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

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

a:hover {
    color: var(--primary-light);
}

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    line-height: var(--line-height-headings);
    margin-bottom: var(--spacing-2);
    font-weight: 700;
    color: var(--text-primary);
}

h1 {
    font-size: 2.5rem; /* 40px */
}

h2 {
    font-size: 2rem; /* 32px */
}

h3 {
    font-size: 1.5rem; /* 24px */
}

h4 {
    font-size: 1.25rem; /* 20px */
}

p {
    margin-bottom: var(--spacing-2);
}

/* Container */
.container {
    width: 90%;
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-2);
}

/* Button Styles */
.btn {
    display: inline-block;
    padding: var(--spacing-1) var(--spacing-3);
    border-radius: var(--border-radius-md);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: none;
    text-align: center;
}

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

.btn-primary:hover {
    background-color: var(--primary-dark);
    color: white;
}

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

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: white;
}

/* Header */
#header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--header-height);
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(5px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: background-color var(--transition-normal), box-shadow var(--transition-normal);
}

.dark-theme #header {
    background-color: rgba(15, 23, 42, 0.95);
}

#header .container {
    height: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo h1 {
    font-size: 1.5rem;
    margin: 0;
    color: var(--primary-color);
}

nav {
    display: flex;
    align-items: center;
}

.nav-menu {
    display: flex;
    list-style: none;
}

.nav-menu li {
    margin-left: var(--spacing-3);
}

.nav-menu a {
    color: var(--text-secondary);
    font-weight: 500;
    padding: var(--spacing-1) 0;
    position: relative;
}

.nav-menu a:hover, .nav-menu a.active {
    color: var(--primary-color);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width var(--transition-fast);
}

.nav-menu a:hover::after, .nav-menu a.active::after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: var(--spacing-1);
}

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

.theme-toggle {
    margin-right: var(--spacing-3);
}

#theme-toggle-btn {
    background: transparent;
    border: none;
    cursor: pointer;
    color: var(--text-secondary);
    font-size: 1.2rem;
    padding: var(--spacing-1);
    display: flex;
    align-items: center;
    justify-content: center;
}

#theme-toggle-btn i {
    transition: opacity var(--transition-fast);
}

#theme-toggle-btn .fa-sun {
    display: none;
}

.dark-theme #theme-toggle-btn .fa-moon {
    display: none;
}

.dark-theme #theme-toggle-btn .fa-sun {
    display: block;
}

/* Hero Section */
.hero {
    padding: calc(var(--header-height) + var(--spacing-5)) 0 var(--spacing-6);
    background: linear-gradient(135deg, rgba(10, 110, 189, 0.05) 0%, rgba(53, 162, 159, 0.05) 100%);
}

.dark-theme .hero {
    background: linear-gradient(135deg, rgba(10, 110, 189, 0.1) 0%, rgba(53, 162, 159, 0.1) 100%);
}

.hero .container {
    display: flex;
    align-items: center;
    gap: var(--spacing-5);
}

.hero-content {
    flex: 1;
}

.hero-content h1 {
    font-size: 3rem;
    margin-bottom: var(--spacing-1);
    color: var(--primary-color);
}

.hero-content h2 {
    font-size: 1.5rem;
    font-weight: 500;
    margin-bottom: var(--spacing-3);
    color: var(--text-secondary);
}

.hero-content p {
    font-size: 1.1rem;
    margin-bottom: var(--spacing-4);
    max-width: 600px;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-2);
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
}

.cloud-graphic {
    font-size: 8rem;
    display: flex;
    gap: var(--spacing-3);
    color: var(--primary-color);
    opacity: 0.8;
}

/* Section Styles */
section {
    padding: var(--spacing-6) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-5);
}

.section-header h2 {
    font-size: 2.2rem;
    color: var(--primary-color);
    position: relative;
    display: inline-block;
    padding-bottom: var(--spacing-2);
}

.section-header h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background-color: var(--accent-color);
}

.section-header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 600px;
    margin: var(--spacing-2) auto 0;
}

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

.timeline::before {
    content: '';
    position: absolute;
    top: 0;
    bottom: 0;
    width: 3px;
    background-color: var(--primary-light);
    left: 50%;
    transform: translateX(-50%);
}

.timeline-item {
    position: relative;
    margin-bottom: var(--spacing-5);
}

.timeline-item:nth-child(even) {
    margin-left: 50%;
}

.timeline-item:nth-child(odd) {
    margin-right: 50%;
    text-align: right;
}

.timeline-item::before {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    background-color: var(--primary-color);
    border-radius: 50%;
    top: 0;
}

.timeline-item:nth-child(even)::before {
    left: -10px;
}

.timeline-item:nth-child(odd)::before {
    right: -10px;
}

.timeline-content {
    background-color: var(--bg-secondary);
    padding: var(--spacing-3);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-md);
    position: relative;
}

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

.timeline-title {
    font-size: 1.2rem;
    margin-bottom: var(--spacing-1);
}

.timeline-company {
    color: var(--text-tertiary);
    margin-bottom: var(--spacing-2);
}

.timeline-description {
    color: var(--text-secondary);
}

/* Projects Section */
.project-filter {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: var(--spacing-2);
    margin-bottom: var(--spacing-4);
}

.filter-btn {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: var(--spacing-1) var(--spacing-2);
    border-radius: var(--border-radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    font-weight: 500;
}

.filter-btn:hover, .filter-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-4);
}

.project-card {
    background-color: var(--bg-secondary);
    border-radius: var(--border-radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.project-image {
    height: 180px;
    background-color: var(--bg-tertiary);
    position: relative;
    overflow: hidden;
}

.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.project-badge {
    position: absolute;
    top: var(--spacing-2);
    right: var(--spacing-2);
    background-color: var(--primary-color);
    color: white;
    padding: 2px var(--spacing-1);
    border-radius: var(--border-radius-sm);
    font-size: 0.8rem;
    font-weight: 600;
}

.project-details {
    padding: var(--spacing-3);
}

.project-title {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-1);
}

.project-description {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: var(--spacing-2);
}

.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-top: var(--spacing-2);
}

.tech-tag {
    background-color: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: 2px 8px;
    border-radius: var(--border-radius-sm);
    font-size: 0.8rem;
}

/* Skills Section */
.skills-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-4);
    margin-bottom: var(--spacing-5);
}

.skills-category {
    background-color: var(--bg-secondary);
    padding: var(--spacing-3);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-md);
}

.skills-category h3 {
    margin-bottom: var(--spacing-3);
    text-align: center;
    color: var(--primary-color);
}

.skill-bar {
    margin-bottom: var(--spacing-2);
}

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

.skill-name {
    font-weight: 500;
    color: var(--text-secondary);
}

.skill-level {
    color: var(--text-tertiary);
    font-size: 0.9rem;
}

.progress-bar {
    height: 8px;
    background-color: var(--bg-tertiary);
    border-radius: 4px;
    overflow: hidden;
}

.progress {
    height: 100%;
    background-color: var(--primary-color);
    border-radius: 4px;
    transition: width 1s ease-in-out;
}

.certifications h3 {
    text-align: center;
    margin-bottom: var(--spacing-3);
    color: var(--primary-color);
}

.certification-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-3);
}

.certification-card {
    background-color: var(--bg-secondary);
    padding: var(--spacing-3);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-md);
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    transition: transform var(--transition-fast);
}

.certification-card:hover {
    transform: translateY(-5px);
}

.certification-logo {
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-2);
    color: var(--primary-color);
    font-size: 2.5rem;
}

.certification-name {
    font-weight: 600;
    margin-bottom: var(--spacing-1);
}

.certification-issuer {
    color: var(--text-tertiary);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-1);
}

.certification-date {
    color: var(--text-secondary);
    font-size: 0.8rem;
}

/* Contact Section */
.contact {
    background-color: var(--bg-tertiary);
    position: relative;
}

.contact-container {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--spacing-4);
}

.contact-info {
    background-color: var(--bg-secondary);
    padding: var(--spacing-3);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-md);
}

.contact-item {
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-3);
}

.contact-item i {
    font-size: 1.2rem;
    color: var(--primary-color);
    margin-right: var(--spacing-2);
    width: 24px;
    text-align: center;
}

.social-links {
    display: flex;
    gap: var(--spacing-2);
    margin-top: var(--spacing-3);
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: var(--bg-tertiary);
    border-radius: 50%;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

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

.contact-form {
    background-color: var(--bg-secondary);
    padding: var(--spacing-3);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-md);
}

.form-group {
    margin-bottom: var(--spacing-3);
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
    color: var(--text-secondary);
}

input, textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-family: var(--font-family);
    font-size: 1rem;
    transition: border-color var(--transition-fast);
}

input:focus, textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.error-message {
    color: var(--error-color);
    font-size: 0.8rem;
    margin-top: 5px;
    display: none;
}

/* Footer */
footer {
    background-color: var(--bg-secondary);
    padding: var(--spacing-4) 0;
    border-top: 1px solid var(--border-color);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--spacing-3);
    margin-bottom: var(--spacing-3);
}

.footer-logo h3 {
    margin-bottom: 5px;
}

.footer-logo p {
    color: var(--text-tertiary);
}

.footer-links {
    display: flex;
    gap: var(--spacing-3);
}

.footer-links a {
    color: var(--text-secondary);
}

.footer-social {
    display: flex;
    gap: var(--spacing-2);
}

.footer-social a {
    color: var(--text-secondary);
    font-size: 1.2rem;
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-2);
    border-top: 1px solid var(--border-color);
    color: var(--text-tertiary);
    font-size: 0.9rem;
}

/* Scroll to Top Button */
.scroll-to-top {
    position: fixed;
    bottom: var(--spacing-3);
    right: var(--spacing-3);
    width: 40px;
    height: 40px;
    background-color: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-md);
    z-index: 99;
}

.scroll-to-top.active {
    opacity: 1;
    visibility: visible;
}

.scroll-to-top:hover {
    background-color: var(--primary-dark);
}

/* Animations */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeIn 0.6s ease forwards;
}

.delay-1 {
    animation-delay: 0.2s;
}

.delay-2 {
    animation-delay: 0.4s;
}

.delay-3 {
    animation-delay: 0.6s;
}

@keyframes fadeIn {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive Styles */
@media (max-width: 992px) {
    .hero .container {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-content {
        margin-bottom: var(--spacing-4);
    }
    
    .hero-cta {
        justify-content: center;
    }
    
    .contact-container {
        grid-template-columns: 1fr;
    }
    
    .timeline::before {
        left: 30px;
    }
    
    .timeline-item:nth-child(even),
    .timeline-item:nth-child(odd) {
        margin-left: 60px;
        margin-right: 0;
        text-align: left;
    }
    
    .timeline-item:nth-child(even)::before,
    .timeline-item:nth-child(odd)::before {
        left: -42px;
        right: auto;
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 60px;
    }
    
    .nav-menu {
        position: fixed;
        top: var(--header-height);
        left: 0;
        width: 100%;
        height: 0;
        background-color: var(--bg-secondary);
        flex-direction: column;
        align-items: center;
        overflow: hidden;
        transition: height var(--transition-normal);
        box-shadow: var(--shadow-md);
    }
    
    .nav-menu.active {
        height: calc(100vh - var(--header-height));
        padding: var(--spacing-3) 0;
    }
    
    .nav-menu li {
        margin: var(--spacing-2) 0;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .mobile-menu-btn.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 6px);
    }
    
    .mobile-menu-btn.active span:nth-child(2) {
        opacity: 0;
    }
    
    .mobile-menu-btn.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -6px);
    }
    
    .footer-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    
    .footer-links {
        flex-wrap: wrap;
        justify-content: center;
    }
}

@media (max-width: 576px) {
    h1 {
        font-size: 2rem;
    }
    
    h2 {
        font-size: 1.75rem;
    }
    
    .hero-content h1 {
        font-size: 2.2rem;
    }
    
    .section-header h2 {
        font-size: 1.8rem;
    }
    
    .project-grid {
        grid-template-columns: 1fr;
    }
    
    .cloud-graphic {
        font-size: 5rem;
    }
}