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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 600px;
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    overflow: hidden;
}

header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 30px;
    text-align: center;
}

header h1 {
    font-size: 2rem;
    margin-bottom: 5px;
}

header p {
    font-size: 0.95rem;
    opacity: 0.9;
}

/* Page tabs (Dosya Yükle / Dosya Havuzu) - keep the site's rounded, soft look */
.page-tabs {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between; /* left tab left, right tab right */
    padding: 8px 18px;
    background: #ffffff;
}

/* purple top stripe like the reference */
.page-tabs::before {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    height: 6px;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
}

.tab {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 12px 20px;
    border-radius: 8px;
    text-decoration: none;
    color: #6b7280;
    background: transparent;
    transition: background 0.18s ease, color 0.18s ease;
    font-weight: 700;
}

.tab:hover {
    color: #374151;
    background: rgba(102,126,234,0.04);
}

/* Active tab: purple text and an underline bar */
.tab.active {
    color: #667eea;
}

.tab.active::after {
    content: '';
    position: absolute;
    left: 12px;
    right: 12px;
    bottom: 0;
    height: 4px;
    border-radius: 4px;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
}

.tab-icon {
    font-size: 1.05rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: 6px;
    background: rgba(102,126,234,0.08);
    color: #667eea;
}

.tab:not(.active) .tab-icon {
    background: rgba(0,0,0,0.04);
    color: #6b7280;
}

.tab-label {
    font-size: 0.95rem;
}

/* per-file select uyumu */
.file-type-select {
    padding: 8px 10px;
    border-radius: 8px;
    border: 1px solid #e5e7eb;
    background: #fff;
    font-weight: 600;
    color: #374151;
}

.file-type-select:focus {
    outline: none;
    box-shadow: 0 6px 18px rgba(102,126,234,0.08);
    border-color: rgba(102,126,234,0.16);
}

main {
    padding: 40px 30px;
}

.upload-area {
    border: 3px dashed #d1d5db;
    border-radius: 15px;
    padding: 50px 20px;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
    background: #f9fafb;
}

.upload-area:hover {
    border-color: #667eea;
    background: #f3f4ff;
}

.upload-area.drag-over {
    border-color: #667eea;
    background: #e0e7ff;
    transform: scale(1.02);
}

.upload-icon {
    font-size: 4rem;
    margin-bottom: 15px;
}

.upload-area h2 {
    font-size: 1.3rem;
    color: #374151;
    margin-bottom: 10px;
}

.upload-area p {
    color: #6b7280;
    margin: 10px 0;
}

.btn-select {
    background: #667eea;
    color: white;
    border: none;
    padding: 12px 30px;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    margin: 15px 0;
}

.btn-select:hover {
    background: #5568d3;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.file-info {
    display: block;
    margin-top: 15px;
    font-size: 0.85rem;
    color: #9ca3af;
}

.file-list {
    margin: 25px 0;
    max-height: 250px;
    overflow-y: auto;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: #f3f4f6;
    padding: 15px;
    border-radius: 10px;
    margin-bottom: 10px;
    transition: all 0.3s ease;
}

.file-item:hover {
    background: #e5e7eb;
}

.file-item-info {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 1;
}

.file-item-icon {
    font-size: 1.5rem;
}

.file-item-details h4 {
    font-size: 0.95rem;
    color: #1f2937;
    margin-bottom: 3px;
}

.file-item-details p {
    font-size: 0.8rem;
    color: #6b7280;
}

.file-item-remove {
    background: #ef4444;
    color: white;
    border: none;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1.2rem;
    transition: all 0.3s ease;
}

.file-item-remove:hover {
    background: #dc2626;
    transform: scale(1.1);
}

.btn-upload {
    width: 100%;
    background: #10b981;
    color: white;
    border: none;
    padding: 15px;
    border-radius: 10px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-upload:hover:not(:disabled) {
    background: #059669;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(16, 185, 129, 0.4);
}

.btn-upload:disabled {
    background: #d1d5db;
    cursor: not-allowed;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: #e5e7eb;
    border-radius: 10px;
    overflow: hidden;
    margin-top: 10px;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    width: 0%;
    transition: width 0.3s ease;
}

footer {
    background: #f9fafb;
    text-align: center;
    padding: 20px;
    color: #6b7280;
    font-size: 0.85rem;
}

.upload-note {
    margin-top: 10px;
    font-size: 0.85rem;
    color: #9ca3af;
    text-align: center;
}