/* ================================
   CSS Variables & Reset
================================ */
:root {
    --primary: #6366f1;
    --secondary: #8b5cf6;
    --accent: #06b6d4;
    --bg-dark: #0f172a;
    --bg-surface: #1e293b;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --border: #334155;
    --success: #22c55e;
    --error: #ef4444;
    --radius: 16px;
    --transition: 300ms ease-out;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* ================================
   Utility Classes
================================ */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary), var(--secondary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

/* ================================
   Navigation
================================ */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
}

.logo:hover {
    opacity: 0.8;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 32px;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
}

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

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

/* ================================
   Hero Section
================================ */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: center;
}

.hero-content {
    max-width: 560px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 24px;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
}

.hero-visual {
    display: flex;
    justify-content: center;
}

.code-window {
    background: var(--bg-surface);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    overflow: hidden;
    width: 100%;
    max-width: 450px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

.code-header {
    display: flex;
    gap: 8px;
    padding: 16px;
    background: rgba(0, 0, 0, 0.3);
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.red { background: #ef4444; }
.dot.yellow { background: #eab308; }
.dot.green { background: #22c55e; }

.code-content {
    padding: 24px;
    font-family: 'Fira Code', 'Consolas', monospace;
    font-size: 0.875rem;
    line-height: 1.8;
    overflow-x: auto;
}

.code-content .keyword { color: #c678dd; }
.code-content .variable { color: #e06c75; }
.code-content .property { color: #e5c07b; }
.code-content .string { color: #98c379; }
.code-content .method { color: #61afef; }

/* ================================
   Buttons
================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: 8px;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(99, 102, 241, 0.5);
}

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

.btn-secondary:hover {
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.1);
}

/* ================================
   Section Styles
================================ */
.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ================================
   Features Section
================================ */
.features {
    padding: 120px 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.feature-card {
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    border-color: var(--primary);
    box-shadow: 0 20px 40px rgba(99, 102, 241, 0.15);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 20px;
}

.feature-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.feature-description {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* ================================
   About Section
================================ */
.about {
    padding: 120px 0;
    background: var(--bg-surface);
}

.about-container {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 64px;
    align-items: center;
}

.about-image {
    display: flex;
    justify-content: center;
}

.image-placeholder {
    width: 300px;
    height: 300px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 6rem;
    box-shadow: 0 25px 50px rgba(99, 102, 241, 0.3);
}

.about-content .section-title {
    text-align: left;
    margin-bottom: 24px;
}

.about-text {
    color: var(--text-secondary);
    margin-bottom: 20px;
    font-size: 1.05rem;
}

.skills {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 32px;
}

.skill-tag {
    background: rgba(99, 102, 241, 0.15);
    color: var(--primary);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    border: 1px solid rgba(99, 102, 241, 0.3);
}

/* ================================
   Contact Section
================================ */
.contact {
    padding: 120px 0;
}

.contact-form {
    max-width: 600px;
    margin: 0 auto;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    font-size: 0.95rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 14px 16px;
    background: var(--bg-surface);
    border: 2px solid var(--border);
    border-radius: 8px;
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--text-secondary);
}

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

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.error-message {
    display: block;
    color: var(--error);
    font-size: 0.85rem;
    margin-top: 6px;
    min-height: 20px;
}

.btn-submit {
    width: 100%;
    position: relative;
}

.btn-submit .btn-loading {
    display: none;
}

.btn-submit.loading .btn-text {
    display: none;
}

.btn-submit.loading .btn-loading {
    display: inline;
}

.form-message {
    display: none;
    padding: 16px;
    border-radius: 8px;
    margin-top: 16px;
    text-align: center;
    font-weight: 500;
}

.form-message.success {
    background: rgba(34, 197, 94, 0.15);
    color: var(--success);
    border: 1px solid rgba(34, 197, 94, 0.3);
}

.form-message.error {
    background: rgba(239, 68, 68, 0.15);
    color: var(--error);
    border: 1px solid rgba(239, 68, 68, 0.3);
}

.form-message.show {
    display: block;
}

/* ================================
   Footer
================================ */
.footer {
    padding: 48px 0;
    border-top: 1px solid var(--border);
}

.footer-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
}

.footer-content {
    text-align: center;
}

.footer-text {
    color: var(--text-secondary);
    margin-top: 8px;
}

.social-links {
    display: flex;
    gap: 16px;
}

.social-link {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: 50%;
    font-size: 1.25rem;
    text-decoration: none;
    transition: var(--transition);
}

.social-link:hover {
    border-color: var(--primary);
    transform: translateY(-2px);
}

.copyright {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* ================================
   Animations
================================ */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

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

/* ================================
   Responsive Design
================================ */
@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-content {
        max-width: 100%;
    }

    .hero-title {
        font-size: 2.75rem;
    }

    .hero-buttons {
        justify-content: center;
    }

    .hero-visual {
        order: -1;
    }

    .code-window {
        max-width: 350px;
    }

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

    .about-container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .about-image {
        order: -1;
    }

    .image-placeholder {
        width: 200px;
        height: 200px;
        font-size: 4rem;
    }

    .about-content .section-title {
        text-align: center;
    }

    .skills {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--bg-dark);
        flex-direction: column;
        padding: 24px;
        gap: 16px;
        border-bottom: 1px solid var(--border);
    }

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

    .mobile-menu-btn {
        display: flex;
    }

    .hero-title {
        font-size: 2.25rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .form-row {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero {
        padding-top: 120px;
    }

    .hero-title {
        font-size: 1.875rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }
}