:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #8b5cf6;
    --secondary: #06d6a0;
    --accent: #f72585;
    --light: #f8fafc;
    --dark: #1e293b;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --gray: #64748b;
    --light-gray: #e2e8f0;
    --sidebar-width: 280px;
    --border-radius: 16px;
    --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 20px 50px -12px rgba(0, 0, 0, 0.25);
    --gradient: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
}

body {
    background-color: #f1f5f9;
    color: var(--dark);
    line-height: 1.6;
    font-size: 16px;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Modern Header */
header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    padding: 15px 0;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    transition: all 0.3s ease;
}

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

.logo {
    font-size: 28px;
    font-weight: 800;
    display: flex;
    align-items: center;
    cursor: pointer;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.logo i {
    margin-right: 12px;
    font-size: 32px;
}

/* Navigation */
.nav-links {
    display: flex;
    gap: 8px;
    background: rgba(255, 255, 255, 0.8);
    padding: 8px;
    border-radius: 50px;
    backdrop-filter: blur(10px);
    border: 1px solid var(--light-gray);
}

.nav-links a {
    color: var(--gray);
    text-decoration: none;
    font-weight: 600;
    padding: 12px 24px;
    border-radius: 50px;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-links a:hover {
    color: var(--primary);
    background: rgba(99, 102, 241, 0.1);
}

.nav-links a.active {
    background: var(--gradient);
    color: white;
    box-shadow: var(--shadow);
}

/* Auth Buttons */
.auth-buttons {
    display: flex;
    gap: 12px;
}

/* User Menu */
.user-menu {
    position: relative;
}

.user-profile {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 8px 16px;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
    background: rgba(255, 255, 255, 0.8);
    border: 1px solid var(--light-gray);
}

.user-profile:hover {
    background: white;
    box-shadow: var(--shadow);
}

.profile-avatar {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 700;
    font-size: 16px;
    border: 3px solid white;
    box-shadow: var(--shadow);
}

.profile-avatar img {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    object-fit: cover;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    right: 0;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    width: 240px;
    z-index: 1000;
    display: none;
    overflow: hidden;
    margin-top: 8px;
    border: 1px solid var(--light-gray);
}

.dropdown-menu.show {
    display: block;
    animation: dropdownSlide 0.2s ease;
}

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

.dropdown-item {
    padding: 16px 20px;
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--dark);
    text-decoration: none;
    transition: all 0.3s ease;
    border-bottom: 1px solid var(--light-gray);
}

.dropdown-item:last-child {
    border-bottom: none;
}

.dropdown-item:hover {
    background: var(--light);
    color: var(--primary);
}

.dropdown-item i {
    width: 20px;
    color: var(--primary);
}

/* Buttons */
.btn {
    padding: 14px 28px;
    border-radius: 50px;
    border: none;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 15px;
    text-decoration: none;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

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

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
}

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

.btn-secondary:hover {
    background: #05c391;
}

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

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

.btn-sm {
    padding: 10px 20px;
    font-size: 14px;
}

.btn-lg {
    padding: 16px 32px;
    font-size: 16px;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000"><polygon fill="%23ffffff" fill-opacity="0.1" points="0,1000 1000,0 1000,1000"/></svg>');
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    color: white;
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 4rem;
    font-weight: 800;
    margin-bottom: 24px;
    line-height: 1.1;
}

.hero p {
    font-size: 1.3rem;
    margin-bottom: 40px;
    opacity: 0.9;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
}

/* Features Grid */
.features {
    padding: 100px 0;
    background: white;
}

.section-title {
    text-align: center;
    margin-bottom: 60px;
}

.section-title h2 {
    font-size: 3rem;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 16px;
}

.section-title p {
    font-size: 1.2rem;
    color: var(--gray);
    max-width: 600px;
    margin: 0 auto;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.feature-card {
    background: white;
    padding: 40px 30px;
    border-radius: var(--border-radius);
    text-align: center;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--light-gray);
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    width: 80px;
    height: 80px;
    background: var(--gradient);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 24px;
    color: white;
    font-size: 2rem;
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 16px;
    color: var(--dark);
}

.feature-card p {
    color: var(--gray);
    line-height: 1.6;
}

/* Project Cards */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
}

.project-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 30px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--light-gray);
    cursor: pointer;
}

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

.project-card h3 {
    color: var(--primary);
    margin-bottom: 12px;
    font-size: 1.3rem;
}

.project-meta {
    display: flex;
    gap: 15px;
    margin: 15px 0;
    color: var(--gray);
    font-size: 0.9rem;
    flex-wrap: wrap;
}

.project-meta span {
    display: flex;
    align-items: center;
    gap: 5px;
}

.progress-container {
    margin: 20px 0;
}

.progress-label {
    display: flex;
    justify-content: space-between;
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: var(--gray);
}

.progress-bar {
    height: 8px;
    background: var(--light-gray);
    border-radius: 10px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--gradient);
    border-radius: 10px;
    transition: width 0.3s ease;
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--dark);
}

.form-control {
    width: 100%;
    padding: 16px 20px;
    border: 2px solid var(--light-gray);
    border-radius: 12px;
    font-size: 16px;
    transition: all 0.3s ease;
    background: white;
}

.form-control:focus {
    border-color: var(--primary);
    outline: none;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

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

/* Modals */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(5px);
    z-index: 2000;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.modal-content {
    background: white;
    padding: 40px;
    border-radius: var(--border-radius);
    width: 100%;
    max-width: 500px;
    box-shadow: var(--shadow-lg);
    position: relative;
    animation: modalSlideIn 0.3s ease;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: scale(0.9) translateY(-20px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 2px solid var(--light-gray);
}

.modal-header h2 {
    color: var(--primary);
    margin: 0;
}

.close-modal {
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--gray);
    transition: color 0.3s;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
}

.close-modal:hover {
    background: var(--light);
    color: var(--danger);
}

/* Tabs */
.tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 30px;
    background: var(--light);
    padding: 8px;
    border-radius: 50px;
}

.tab-btn {
    padding: 12px 24px;
    background: transparent;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    color: var(--gray);
}

.tab-btn.active {
    background: var(--gradient);
    color: white;
    box-shadow: var(--shadow);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Status Badges */
.status-badge {
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.status-active {
    background: #d1fae5;
    color: #065f46;
}

.status-inactive {
    background: #fef3c7;
    color: #92400e;
}

.status-pending {
    background: #dbeafe;
    color: #1e40af;
}

.status-approved {
    background: #d1fae5;
    color: #065f46;
}

.status-rejected {
    background: #fee2e2;
    color: #991b1b;
}

/* Footer */
footer {
    background: var(--dark);
    color: white;
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3 {
    color: var(--secondary);
    margin-bottom: 20px;
    font-size: 1.3rem;
}

.footer-section p {
    margin-bottom: 12px;
    opacity: 0.8;
}

.footer-section a {
    color: white;
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.3s;
}

.footer-section a:hover {
    opacity: 1;
    color: var(--secondary);
}

.social-icons {
    display: flex;
    gap: 15px;
    margin-top: 20px;
}

.social-icons a {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.social-icons a:hover {
    background: var(--secondary);
    transform: translateY(-2px);
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    opacity: 0.7;
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .hero p {
        font-size: 1.1rem;
    }
    
    .nav-links {
        display: none;
    }
    
    .feature-grid,
    .project-grid {
        grid-template-columns: 1fr;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .modal-content {
        margin: 20px;
        padding: 30px 20px;
    }
}

/* Utility Classes */
.text-center { text-align: center; }
.mb-20 { margin-bottom: 20px; }
.mb-30 { margin-bottom: 30px; }
.mt-20 { margin-top: 20px; }
.mt-30 { margin-top: 30px; }

/* Loading Spinner */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255,255,255,.3);
    border-radius: 50%;
    border-top-color: #fff;
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Profil sayfası için ek stiller */
.profile-avatar-large {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    background: var(--gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: bold;
    font-size: 3rem;
    margin: 0 auto 20px;
    border: 4px solid white;
    box-shadow: var(--shadow);
}

.profile-avatar-large img {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    object-fit: cover;
}

/* Proje detay modal için */
.project-detail {
    max-width: 100%;
}

.project-detail-header {
    border-bottom: 2px solid var(--light-gray);
    padding-bottom: 20px;
    margin-bottom: 20px;
}

.project-detail-body {
    line-height: 1.8;
}

/* Responsive iyileştirmeler */
@media (max-width: 768px) {
    .project-grid {
        grid-template-columns: 1fr;
    }
    
    .hero h1 {
        font-size: 2.2rem;
    }
    
    .section-title h2 {
        font-size: 2.2rem;
    }
    
    .modal-content {
        margin: 10px;
        padding: 20px;
    }
}

/* Text center utility */
.text-center {
    text-align: center;
}

/* Margin utilities */
.mt-20 { margin-top: 20px; }
.mb-20 { margin-bottom: 20px; }
.mt-30 { margin-top: 30px; }
.mb-30 { margin-bottom: 30px; }

/* File input styling */
.form-control[type="file"] {
    padding: 12px;
}

/* Success and error message improvements */
.success-message, .error-message {
    padding: 15px;
    border-radius: 12px;
    margin: 15px 0;
    font-weight: 500;
}

.success-message {
    background: #d1fae5;
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.error-message {
    background: #fee2e2;
    color: #991b1b;
    border: 1px solid #fecaca;
}