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

body {
    font-family: Arial, sans-serif;
    background-color: #f8fafc;
    color: #0f172a;
    min-height: 100vh;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #e2e8f0;
    z-index: 50;
}

.nav-container {
    max-width: 896px;
    margin: 0 auto;
    padding: 1rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.25rem;
    font-weight: 600;
}

.nav-links {
    display: flex;
    gap: 1.5rem;
}

.nav-btn {
    background: none;
    border: none;
    color: #64748b;
    font-size: 1rem;
    cursor: pointer;
    transition: color 0.3s;
}

.nav-btn:hover {
    color: #334155;
}

.nav-btn.active {
    color: #0f172a;
    font-weight: 500;
}

/* Container */
.container {
    max-width: 896px;
    margin: 0 auto;
    padding: 8rem 1.5rem 5rem;
}

/* Sections */
.section {
    display: none;
    animation: fadeIn 0.5s ease-out;
}

.section.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Home Section */
.hero {
    margin-bottom: 3rem;
}

.title {
    font-size: 3.75rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #0f172a;
}

.subtitle {
    font-size: 1.5rem;
    color: #475569;
    margin-bottom: 1.5rem;
}

.description {
    font-size: 1.125rem;
    color: #64748b;
    max-width: 42rem;
}

.button-group {
    display: flex;
    gap: 1rem;
}

.btn {
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 500;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.3s;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    border: none;
}

.btn-primary {
    background-color: #0f172a;
    color: white;
}

.btn-primary:hover {
    background-color: #1e293b;
}

.btn-secondary {
    background-color: transparent;
    color: #0f172a;
    border: 2px solid #0f172a;
}

.btn-secondary:hover {
    background-color: #0f172a;
    color: white;
}

/* Projects Section */
.section-header {
    margin-bottom: 2rem;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.section-description {
    color: #475569;
}

.project-card {
    background: white;
    border-radius: 1rem;
    padding: 2rem;
    margin-bottom: 2rem;
    border: 1px solid #e2e8f0;
    cursor: pointer;
    transition: all 0.3s;
}

.project-card:hover {
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    border-color: #cbd5e1;
}

.project-card.placeholder {
    background-color: #f1f5f9;
    cursor: default;
    text-align: center;
    color: #475569;
}

.project-card.placeholder:hover {
    box-shadow: none;
    border-color: #e2e8f0;
}

.project-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.project-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.project-description {
    color: #475569;
    margin-bottom: 0.75rem;
}

.project-hint {
    font-size: 0.875rem;
    color: #64748b;
    font-style: italic;
}

.project-icon {
    color: #cbd5e1;
}

.project-tags {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.tag {
    padding: 0.25rem 0.75rem;
    background-color: #f1f5f9;
    color: #334155;
    border-radius: 9999px;
    font-size: 0.875rem;
}

/* Calculator Section */
.back-btn {
    background: none;
    border: none;
    color: #475569;
    font-size: 1rem;
    cursor: pointer;
    margin-bottom: 1.5rem;
    transition: color 0.3s;
}

.back-btn:hover {
    color: #0f172a;
}

.calculator-container {
    background: white;
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    border: 1px solid #e2e8f0;
}

.calculator-title {
    font-size: 1.875rem;
    font-weight: 700;
    color: #0f172a;
    margin-bottom: 1.5rem;
}

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

.form-label {
    display: block;
    font-size: 1.125rem;
    font-weight: 600;
    color: #334155;
    margin-bottom: 0.75rem;
}

.radio-group {
    display: flex;
    gap: 1.5rem;
}

.radio-option {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
}

.radio-option input[type="radio"] {
    width: 1rem;
    height: 1rem;
    cursor: pointer;
}

.radio-option span {
    color: #334155;
}

.input-field {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid #cbd5e1;
    border-radius: 0.5rem;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.input-field:focus {
    outline: none;
    border-color: #0f172a;
}

.btn-calculate {
    width: 100%;
    background-color: #0f172a;
    color: white;
    padding: 0.75rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: background-color 0.3s;
    border: none;
}

.btn-calculate:hover {
    background-color: #1e293b;
}

.results {
    margin-top: 1.5rem;
    background-color: #f8fafc;
    border-radius: 0.75rem;
    padding: 1.5rem;
    border: 1px solid #e2e8f0;
    display: none;
}

.results.show {
    display: block;
}

.results h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: #0f172a;
    margin-bottom: 1rem;
}

.result-item {
    background: white;
    padding: 1rem;
    border-radius: 0.5rem;
    border: 1px solid #e2e8f0;
    margin-bottom: 1rem;
}

.result-item:last-child {
    margin-bottom: 0;
}

.result-item p {
    color: #334155;
}

.result-item strong {
    font-weight: 600;
}

.hole-list {
    padding-left: 1rem;
    margin-top: 0.75rem;
}

.hole-list div {
    color: #334155;
    margin-bottom: 0.5rem;
}

.hole-list span {
    font-family: 'Courier New', monospace;
    font-weight: 600;
}

.error {
    color: #dc2626;
    font-weight: 600;
}

/* About Section */
.about-content {
    margin-bottom: 3rem;
}

.about-text {
    font-size: 1.125rem;
    color: #334155;
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

.skills-section {
    margin-bottom: 3rem;
}

.skills-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.skills-grid {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.skill-tag {
    padding: 0.5rem 1rem;
    background-color: white;
    border: 2px solid #e2e8f0;
    border-radius: 0.5rem;
}

.skill-tag.primary {
    background-color: #0f172a;
    color: white;
    border-color: #0f172a;
}

.contact-section {
    padding-top: 2rem;
    border-top: 1px solid #e2e8f0;
}

.contact-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.contact-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: #334155;
    text-decoration: none;
    transition: color 0.3s;
}

.contact-link:hover {
    color: #0f172a;
}

/* Responsive */
@media (max-width: 768px) {
    .title {
        font-size: 2.5rem;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .radio-group {
        flex-direction: column;
        gap: 0.75rem;
    }
}