/* ==========================================================================
   CSS Variables & Reset
   ========================================================================== */
:root {
    /* Color Palette */
    --color-bg: #FFFFFF;
    --color-text: #111111;
    --color-text-muted: #555555;
    
    --color-primary: #E63946; /* Vibrant Red */
    --color-primary-dark: #C1121F;
    
    --color-secondary: #0A369D; /* Deep Blue */
    --color-secondary-light: #4A90E2;

    --color-surface: #F8F9FA;
    --color-border: #E0E0E0;

    /* Typography */
    --font-main: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    
    /* Spacing & Layout */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    
    --container-max: 1200px;
    --border-radius: 8px;
    --transition-speed: 0.3s;
}

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

body {
    font-family: var(--font-main);
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    overflow-x: hidden;
}

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

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

/* ==========================================================================
   Typography & Utilities
   ========================================================================== */
h1, h2, h3, h4 {
    line-height: 1.2;
    margin-bottom: var(--spacing-sm);
    font-weight: 700;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    border: 2px solid transparent;
}

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

.btn-primary:hover {
    background-color: var(--color-primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(230, 57, 70, 0.3);
}

.btn-secondary {
    background-color: var(--color-bg);
    color: var(--color-secondary);
    border-color: var(--color-secondary);
}

.btn-secondary:hover {
    background-color: var(--color-secondary);
    color: var(--color-bg);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(10, 54, 157, 0.2);
}

/* ==========================================================================
   Navbar
   ========================================================================== */
.navbar {
    position: sticky;
    top: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
}

.nav-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--spacing-sm) var(--spacing-md);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--color-text);
    letter-spacing: -0.5px;
}

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

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

.nav-links a {
    font-weight: 500;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--color-secondary);
    transition: width var(--transition-speed) ease;
}

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

.nav-links a.active {
    color: var(--color-secondary);
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.hamburger {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-text);
    position: relative;
    transition: background-color 0.2s;
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--color-text);
    transition: transform 0.2s;
}

.hamburger::before { top: -6px; }
.hamburger::after { bottom: -6px; }

/* Mobile Menu Toggle State */
.menu-toggle.is-active .hamburger { background-color: transparent; }
.menu-toggle.is-active .hamburger::before { transform: translateY(6px) rotate(45deg); }
.menu-toggle.is-active .hamburger::after { transform: translateY(-6px) rotate(-45deg); }

/* ==========================================================================
   Home / Hero
   ========================================================================== */
.hero {
    flex: 1;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--spacing-lg) var(--spacing-md);
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
    align-items: center;
}

.greeting {
    font-size: 1.125rem;
    color: var(--color-secondary);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.title {
    font-size: 4rem;
    margin-bottom: var(--spacing-xs);
    color: var(--color-text);
}

.subtitle {
    font-size: 1.5rem;
    color: var(--color-text-muted);
    font-weight: 400;
}

.description {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    max-width: 500px;
    margin-bottom: var(--spacing-md);
}

.cta-group {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

/* Abstract Server Graphic Animation */
.hero-graphic {
    position: relative;
    width: 100%;
    max-width: 400px;
    margin: 0 auto;
}

.server-rack {
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    padding: var(--spacing-sm);
    box-shadow: 0 20px 40px rgba(0,0,0,0.05);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.server-node {
    height: 40px;
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: 4px;
    position: relative;
    overflow: hidden;
}

.server-node::before {
    content: '';
    position: absolute;
    left: 10px;
    top: 50%;
    transform: translateY(-50%);
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--color-primary);
}

.animate-pulse::before {
    animation: pulse 2s infinite;
}

.delay-1::before { animation-delay: 0.5s; }
.delay-2::before { animation-delay: 1s; }

@keyframes pulse {
    0% { transform: translateY(-50%) scale(0.95); box-shadow: 0 0 0 0 rgba(230, 57, 70, 0.7); }
    70% { transform: translateY(-50%) scale(1); box-shadow: 0 0 0 6px rgba(230, 57, 70, 0); }
    100% { transform: translateY(-50%) scale(0.95); box-shadow: 0 0 0 0 rgba(230, 57, 70, 0); }
}

/* ==========================================================================
   Internal Pages (Skills / Contact)
   ========================================================================== */
.page-container {
    flex: 1;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--spacing-md);
    width: 100%;
}

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

.page-header h1 {
    font-size: 3rem;
    color: var(--color-secondary);
}

.page-header p {
    font-size: 1.25rem;
    color: var(--color-text-muted);
}

/* Skills Grid */
.skills-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

.skill-card {
    background-color: var(--color-surface);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    border: 1px solid var(--color-border);
    transition: transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
}

.skill-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
    border-color: var(--color-secondary-light);
}

.skill-icon {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

/* Contact Section */
.contact-section {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
}

.contact-card {
    background-color: var(--color-secondary);
    color: var(--color-bg);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
}

.contact-card h2 {
    color: var(--color-bg);
}

.contact-list {
    list-style: none;
    margin-top: var(--spacing-md);
}

.contact-list li {
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-sm);
    font-size: 1.125rem;
}

.contact-list .icon {
    margin-right: var(--spacing-sm);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.form-group {
    display: flex;
    flex-direction: column;
}

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

.form-group input,
.form-group textarea {
    padding: 0.75rem;
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    font-family: inherit;
    font-size: 1rem;
    transition: border-color var(--transition-speed) ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-secondary);
}

.submit-btn {
    align-self: flex-start;
    margin-top: var(--spacing-sm);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.footer {
    background-color: var(--color-surface);
    border-top: 1px solid var(--color-border);
    padding: var(--spacing-md);
    margin-top: auto;
}

.footer-content {
    max-width: var(--container-max);
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    text-align: center;
    color: var(--color-text-muted);
}

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

.footer-links a {
    font-weight: 600;
}

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

/* ==========================================================================
   Media Queries
   ========================================================================== */

@media (min-width: 768px) {
    .hero {
        grid-template-columns: 1fr 1fr;
    }

    .title {
        font-size: 5rem;
    }

    .skills-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .contact-section {
        grid-template-columns: 1fr 1fr;
    }

    .footer-content {
        flex-direction: row;
        justify-content: space-between;
    }
}

@media (max-width: 767px) {
    .menu-toggle {
        display: block;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: var(--color-bg);
        flex-direction: column;
        padding: var(--spacing-md);
        border-bottom: 1px solid var(--color-border);
        box-shadow: 0 10px 20px rgba(0,0,0,0.05);
    }

    .nav-links.nav-open {
        display: flex;
    }

    .hero {
        text-align: center;
    }

    .cta-group {
        justify-content: center;
    }
}