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

:root {
    --bg-color: #030305;
    --bg-secondary: #0a0a0f;
    --bg-tertiary: #12121a;
    --text-main: #ffffff;
    --text-muted: #9494a8;
    --primary: #00eaff;
    --secondary: #ff00c8;
    --accent: #7000ff;
    --success: #00ff88;
    --glass-bg: rgba(20, 20, 25, 0.6);
    --glass-border: rgba(255, 255, 255, 0.08);
    --card-radius: 16px;
    --transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

body {
    font-family: 'Outfit', sans-serif;
    background: var(--bg-color);
    color: var(--text-main);
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 25px;
    padding: 25px 20px;
    background: var(--glass-bg);
    border-radius: var(--card-radius);
    border: 1px solid var(--glass-border);
    position: relative;
}

.back-link {
    position: absolute;
    top: 20px;
    left: 20px;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

.back-link:hover { color: var(--primary); }

header h1 {
    font-size: 2rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

header h1 i { margin-right: 10px; }

.subtitle { color: var(--text-muted); font-size: 0.95rem; }

.tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

.tab-btn {
    flex: 1;
    padding: 14px 20px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    color: var(--text-muted);
    font-family: inherit;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.tab-btn:hover { border-color: var(--primary); color: var(--primary); }

.tab-btn.active {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    border-color: transparent;
    color: #000;
}

.tab-btn i { margin-right: 8px; }

.tab-content { display: none; }

.tab-content.active { display: block; }

.upload-area {
    background: var(--glass-bg);
    border: 2px dashed var(--glass-border);
    border-radius: var(--card-radius);
    padding: 60px 30px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    margin-bottom: 20px;
}

.upload-area:hover {
    border-color: var(--primary);
    background: rgba(0, 234, 255, 0.05);
}

.upload-area.dragover {
    border-color: var(--primary);
    background: rgba(0, 234, 255, 0.1);
}

.upload-area i {
    font-size: 3rem;
    color: var(--primary);
    margin-bottom: 15px;
}

.upload-area p {
    font-size: 1.1rem;
    margin-bottom: 8px;
}

.upload-area span {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.panel {
    background: var(--glass-bg);
    border-radius: var(--card-radius);
    border: 1px solid var(--glass-border);
    padding: 20px;
    margin-bottom: 20px;
}

.panel.hidden { display: none; }

.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.panel-header h2 {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.panel-header h2 i { margin-right: 8px; color: var(--primary); }

.btn-small {
    background: var(--bg-tertiary);
    border: 1px solid var(--glass-border);
    border-radius: 8px;
    padding: 8px 14px;
    color: var(--text-muted);
    font-size: 0.8rem;
    cursor: pointer;
    transition: var(--transition);
}

.btn-small:hover { color: var(--primary); border-color: var(--primary); }

.preview-container {
    background: repeating-conic-gradient(#1a1a2e 0% 25%, #12121a 0% 50%) 50% / 20px 20px;
    border-radius: 12px;
    padding: 20px;
    text-align: center;
    margin-bottom: 15px;
}

.preview-container img, .decoded-preview img {
    max-width: 100%;
    max-height: 300px;
    border-radius: 8px;
}

.image-info {
    display: flex;
    justify-content: center;
    gap: 20px;
    color: var(--text-muted);
    font-size: 0.85rem;
}

.image-info span { color: var(--text-main); }

.output-options {
    display: flex;
    gap: 15px;
}

.output-options label {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.8rem;
    color: var(--text-muted);
    cursor: pointer;
}

textarea {
    width: 100%;
    min-height: 150px;
    padding: 15px;
    background: var(--bg-tertiary);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    color: var(--text-main);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.8rem;
    resize: vertical;
    outline: none;
    margin-bottom: 15px;
    transition: var(--transition);
}

textarea:focus { border-color: var(--primary); }

textarea::placeholder { color: var(--text-muted); opacity: 0.5; }

.actions {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 20px;
    border-radius: 10px;
    font-family: inherit;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    color: #000;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(0, 234, 255, 0.3);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-main);
    border: 1px solid var(--glass-border);
}

.btn-secondary:hover { border-color: var(--secondary); color: var(--secondary); }

.decoded-preview {
    background: repeating-conic-gradient(#1a1a2e 0% 25%, #12121a 0% 50%) 50% / 20px 20px;
    border-radius: 12px;
    padding: 20px;
    text-align: center;
    margin-bottom: 15px;
}

.image-size {
    font-size: 0.8rem;
    color: var(--text-muted);
}

select {
    padding: 12px 15px;
    background: var(--bg-tertiary);
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    color: var(--text-main);
    font-family: inherit;
    font-size: 0.9rem;
    cursor: pointer;
    outline: none;
}

.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--bg-tertiary);
    border: 1px solid var(--success);
    border-radius: 10px;
    padding: 12px 24px;
    color: var(--success);
    font-size: 0.9rem;
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 1000;
}

.toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

.toast.error { border-color: #ff4757; color: #ff4757; }

footer {
    text-align: center;
    padding: 20px;
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-top: 20px;
}

@media (max-width: 500px) {
    .container { padding: 15px; }
    header h1 { font-size: 1.6rem; }
    .tabs { flex-direction: column; }
    .actions { flex-direction: column; }
    .btn { justify-content: center; }
}