:root {
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --bg-dark: #0f172a;
    --card-bg: rgba(30, 41, 59, 0.7);
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --accent: #a855f7;
    --glass: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
}

body {
    background-color: var(--bg-dark);
    background-image:
        radial-gradient(circle at 0% 0%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 100% 100%, rgba(168, 85, 247, 0.15) 0%, transparent 50%);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow-x: hidden;
}

.container {
    width: 90%;
    max-width: 1000px;
    padding: 40px 0;
    animation: fadeIn 0.8s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

header {
    text-align: center;
    margin-bottom: 50px;
}

header h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 10px;
    letter-spacing: -1px;
}

header h1 span {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-muted);
    font-size: 1.1rem;
}

.upload-box {
    background: var(--card-bg);
    -webkit-backdrop-filter: blur(12px);
    backdrop-filter: blur(12px);
    border: 2px dashed var(--glass-border);
    border-radius: 24px;
    padding: 60px 40px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.upload-box:hover {
    border-color: var(--primary);
    background: rgba(30, 41, 59, 0.9);
    transform: scale(1.02);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
}

.upload-icon {
    width: 64px;
    height: 64px;
    color: var(--primary);
    margin-bottom: 20px;
}

.upload-box h3 {
    font-size: 1.5rem;
    margin-bottom: 10px;
}

.upload-box p {
    color: var(--text-muted);
    margin-bottom: 30px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    color: white;
    border: none;
    padding: 12px 32px;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s;
    text-decoration: none;
    display: inline-block;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(99, 102, 241, 0.3);
}

.btn-primary.disabled {
    opacity: 0.5;
    pointer-events: none;
}

.btn-secondary {
    background: var(--glass);
    color: var(--text-main);
    border: 1px solid var(--glass-border);
    padding: 12px 32px;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
}

.process-box {
    background: var(--card-bg);
    -webkit-backdrop-filter: blur(12px);
    backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 40px;
    animation: slideUp 0.5s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(40px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.preview-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 40px;
}

.preview-item {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.label {
    font-weight: 600;
    color: var(--text-muted);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.img-wrapper {
    aspect-ratio: 4/3;
    background: var(--bg-dark);
    border-radius: 16px;
    overflow: hidden;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    border: 1px solid var(--glass-border);
}

/* 격자 무늬 배경 (PNG 투명 표현) */
#result-preview {
    background-image:
        linear-gradient(45deg, #222 25%, transparent 25%),
        linear-gradient(-45deg, #222 25%, transparent 25%),
        linear-gradient(45deg, transparent 75%, #222 75%),
        linear-gradient(-45deg, transparent 75%, #222 75%);
    background-size: 20px 20px;
    background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
}

.img-wrapper img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.loader-container {
    text-align: center;
    padding: 20px;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--glass);
    border-top: 4px solid var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

.progress-bar {
    width: 200px;
    height: 6px;
    background: var(--glass);
    border-radius: 3px;
    margin: 20px auto 0;
    overflow: hidden;
}

.progress-fill {
    width: 0%;
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    transition: width 0.3s;
}

.actions {
    display: flex;
    justify-content: center;
    gap: 20px;
}

.hidden {
    display: none !important;
}

footer {
    margin-top: 50px;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

@media (max-width: 768px) {
    .preview-container {
        grid-template-columns: 1fr;
    }

    header h1 {
        font-size: 2.5rem;
    }
}