body.dark-mode{background:linear-gradient(135deg,#1a1a2e 0%,#16213e 100%)}.header h1{color:white;font-size:28px;font-weight:700}body.dark-mode .card{background:#0f3460;color:white}.upload-area.dragover{background:rgba(102,126,234,.1);border-color:#764ba2;transform:scale(1.02)}body.dark-mode .upload-area{border-color:#00d4ff}body.dark-mode .upload-area:hover{border-color:#00a8cc;background:rgba(0,212,255,.05)}body.dark-mode .upload-text{color:#ccc}body.dark-mode .preview-title{color:white}body.dark-mode .preview-label{color:#ccc}body.dark-mode .preview-value{color:white}body.dark-mode .btn-secondary{background:#1a1a2e;color:white}body.dark-mode .btn-secondary:hover{background:#2a2a3e}body.dark-mode .ai-title{color:white}.ai-message{background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);padding:15px;border-radius:12px;color:white;margin-bottom:15px;animation:slideIn .5s ease}body.dark-mode .ai-message{background:linear-gradient(135deg,#00d4ff 0%,#00a8cc 100%)}body.dark-mode .ai-tip{background:rgba(0,212,255,.1);color:white;border-left-color:#00d4ff}body.dark-mode .history-title{color:white}.history-item{position:relative;aspect-ratio:1;border-radius:8px;overflow:hidden;cursor:pointer;transition:transform .3s ease}.history-item:hover{transform:scale(1.05)}.history-item img{width:100%;height:100%;object-fit:cover}@media (max-width:768px){.header h1{font-size:22px}}