:root {
    /* Dark mode (default) */
    --bg-primary: #0a0a0f;
    --bg-secondary: #1a1a2e;
    --bg-tertiary: #0f0f1a;
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.9);
    --text-muted: rgba(255, 255, 255, 0.6);
    --text-dim: rgba(255, 255, 255, 0.4);
    --text-dimmer: rgba(255, 255, 255, 0.3);
    --card-bg: rgba(255, 255, 255, 0.03);
    --card-border: rgba(255, 255, 255, 0.08);
    --card-highlight: rgba(255, 255, 255, 0.05);
    --upload-bg: rgba(255, 255, 255, 0.02);
    --upload-border: rgba(255, 255, 255, 0.15);
    --file-item-bg: rgba(255, 255, 255, 0.05);
    --loader-bg: rgba(255, 255, 255, 0.03);
    --particle-connection: rgba(255, 255, 255, 0.02);
    --glow-color: rgba(99, 102, 241, 0.1);
    --shadow-color: rgba(0, 0, 0, 0.3);
}

[data-theme="light"] {
    --bg-primary: #f8fafc;
    --bg-secondary: #e2e8f0;
    --bg-tertiary: #f1f5f9;
    --text-primary: #0f172a;
    --text-secondary: #1e293b;
    --text-muted: #64748b;
    --text-dim: #94a3b8;
    --text-dimmer: #cbd5e1;
    --card-bg: rgba(255, 255, 255, 0.8);
    --card-border: rgba(0, 0, 0, 0.08);
    --card-highlight: rgba(255, 255, 255, 0.5);
    --upload-bg: rgba(99, 102, 241, 0.02);
    --upload-border: rgba(99, 102, 241, 0.2);
    --file-item-bg: rgba(99, 102, 241, 0.05);
    --loader-bg: rgba(99, 102, 241, 0.05);
    --particle-connection: rgba(99, 102, 241, 0.08);
    --glow-color: rgba(99, 102, 241, 0.15);
    --shadow-color: rgba(99, 102, 241, 0.1);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    min-height: 100vh;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 50%, var(--bg-tertiary) 100%);
    color: var(--text-primary);
    overflow-x: hidden;
    transition: background 0.3s ease, color 0.3s ease;
}

#particleCanvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
}

.app-container {
    position: relative;
    z-index: 1;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.header {
    text-align: center;
    margin-bottom: 2.5rem;
}

.logo {
    font-size: 3rem;
    font-weight: 700;
    background: linear-gradient(135deg, #6366f1 0%, #a855f7 50%, #ec4899 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.tagline {
    font-size: 1.1rem;
    color: var(--text-muted);
    font-weight: 400;
}

.theme-toggle {
    position: fixed;
    top: 1.5rem;
    right: 1.5rem;
    z-index: 100;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: 1px solid var(--card-border);
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px var(--shadow-color);
}

.theme-toggle:hover {
    transform: scale(1.1);
    border-color: #a855f7;
}

.theme-toggle svg {
    width: 22px;
    height: 22px;
    transition: all 0.3s ease;
}

.theme-toggle .sun-icon {
    stroke: #f59e0b;
    display: none;
}

.theme-toggle .moon-icon {
    stroke: var(--text-muted);
}

[data-theme="light"] .theme-toggle .sun-icon {
    display: block;
}

[data-theme="light"] .theme-toggle .moon-icon {
    display: none;
}

.card {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    padding: 2.5rem;
    width: 100%;
    max-width: 520px;
    box-shadow:
        0 4px 24px var(--shadow-color),
        0 0 80px var(--glow-color),
        inset 0 1px 0 var(--card-highlight);
    transition: background 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

[data-theme="light"] .card {
    background: rgba(255, 255, 255, 0.12);
    border: 1px solid rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    box-shadow:
        0 8px 32px rgba(99, 102, 241, 0.1),
        0 0 60px rgba(99, 102, 241, 0.06),
        0 0 0 1px rgba(255, 255, 255, 0.3) inset;
}

.upload-zone {
    border: 2px dashed var(--upload-border);
    border-radius: 16px;
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: var(--upload-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
}

[data-theme="light"] .upload-zone {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(99, 102, 241, 0.25);
    box-shadow:
        0 4px 16px rgba(99, 102, 241, 0.08),
        0 0 0 1px rgba(255, 255, 255, 0.25) inset;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
}

[data-theme="light"] .upload-zone:hover {
    background: rgba(255, 255, 255, 0.18);
    border-color: rgba(99, 102, 241, 0.4);
    box-shadow:
        0 8px 24px rgba(99, 102, 241, 0.12),
        0 0 0 1px rgba(255, 255, 255, 0.35) inset;
}

[data-theme="light"] .upload-zone.has-files {
    background: rgba(34, 197, 94, 0.06);
    border-color: rgba(34, 197, 94, 0.35);
    box-shadow:
        0 4px 16px rgba(34, 197, 94, 0.08),
        0 0 0 1px rgba(255, 255, 255, 0.25) inset;
}

.upload-zone::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.1) 0%, rgba(168, 85, 247, 0.1) 100%);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.upload-zone:hover {
    border-color: rgba(99, 102, 241, 0.5);
    transform: translateY(-2px);
}

.upload-zone:hover::before {
    opacity: 1;
}

.upload-zone.drag-over {
    border-color: #a855f7;
    background: rgba(168, 85, 247, 0.1);
}

.upload-zone.has-files {
    border-color: rgba(34, 197, 94, 0.5);
    background: rgba(34, 197, 94, 0.05);
}

.upload-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 1.25rem;
    position: relative;
    z-index: 1;
}

.upload-icon svg {
    width: 100%;
    height: 100%;
    stroke: var(--text-dim);
    transition: stroke 0.3s ease;
}

.upload-zone:hover .upload-icon svg {
    stroke: #a855f7;
}

.upload-text {
    position: relative;
    z-index: 1;
}

.upload-text h3 {
    font-size: 1.1rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

.upload-text p {
    font-size: 0.875rem;
    color: var(--text-dim);
}

.file-list {
    margin-top: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.file-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    background: var(--file-item-bg);
    border-radius: 10px;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-10px);
    }

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

.file-item .file-icon {
    width: 36px;
    height: 36px;
    border-radius: 8px;
    background: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.file-item .file-icon svg {
    width: 18px;
    height: 18px;
    stroke: white;
}

.file-item .file-info {
    flex: 1;
    min-width: 0;
}

.file-item .file-name {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.file-item .file-size {
    font-size: 0.75rem;
    color: var(--text-dim);
}

.file-item .file-preview {
    width: 36px;
    height: 36px;
    border-radius: 8px;
    object-fit: cover;
}

.submit-btn {
    width: 100%;
    margin-top: 1.5rem;
    padding: 1rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    color: white;
    background: linear-gradient(135deg, #6366f1 0%, #a855f7 50%, #ec4899 100%);
    border: none;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.submit-btn::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, #4f46e5 0%, #9333ea 50%, #db2777 100%);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.submit-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.4);
}

.submit-btn:hover:not(:disabled)::before {
    opacity: 1;
}

.submit-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.submit-btn span {
    position: relative;
    z-index: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.loader-container {
    display: none;
    flex-direction: column;
    align-items: center;
    margin-top: 2rem;
    padding: 2rem;
    background: var(--loader-bg);
    border-radius: 16px;
}

.loader-container.active {
    display: flex;
}

.loader {
    width: 48px;
    height: 48px;
    position: relative;
}

.loader::before,
.loader::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 50%;
    border: 3px solid transparent;
}

.loader::before {
    border-top-color: #6366f1;
    animation: spin 1s linear infinite;
}

.loader::after {
    border-right-color: #a855f7;
    animation: spin 1.5s linear infinite reverse;
}

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

.loader-text {
    margin-top: 1rem;
    font-size: 0.875rem;
    color: var(--text-muted);
}

.loader-subtext {
    font-size: 0.75rem;
    color: var(--text-dimmer);
    margin-top: 0.25rem;
}

.results {
    margin-top: 1.5rem;
}

.result-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem 1.25rem;
    background: rgba(34, 197, 94, 0.1);
    border: 1px solid rgba(34, 197, 94, 0.2);
    border-radius: 12px;
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }

    to {
        opacity: 1;
        transform: scale(1);
    }
}

.result-item .success-icon {
    width: 40px;
    height: 40px;
    background: rgba(34, 197, 94, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.result-item .success-icon svg {
    width: 20px;
    height: 20px;
    stroke: #22c55e;
}

.result-item .result-text {
    flex: 1;
}

.result-item .result-title {
    font-weight: 600;
    color: #22c55e;
    font-size: 0.9375rem;
}

.result-item .result-desc {
    font-size: 0.8125rem;
    color: var(--text-muted);
    margin-top: 0.125rem;
}

.footer {
    margin-top: 2rem;
    text-align: center;
    font-size: 0.8125rem;
    color: var(--text-dimmer);
}

.footer a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer a:hover {
    color: #a855f7;
}

/* Viewer styles */
.viewer-container {
    display: none;
    flex-direction: column;
    width: 100%;
    max-width: 900px;
    margin-top: 1.5rem;
}

.viewer-container.active {
    display: flex;
}

.viewer-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.25rem;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px 16px 0 0;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.viewer-title {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.viewer-title h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.viewer-title .file-badge {
    font-size: 0.75rem;
    padding: 0.25rem 0.75rem;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.2), rgba(168, 85, 247, 0.2));
    border-radius: 20px;
    color: var(--text-muted);
}

.viewer-actions {
    display: flex;
    gap: 0.5rem;
}

.viewer-btn {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    font-weight: 500;
    font-family: inherit;
    color: var(--text-secondary);
    background: var(--file-item-bg);
    border: 1px solid var(--card-border);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.viewer-btn:hover {
    background: rgba(99, 102, 241, 0.15);
    border-color: rgba(99, 102, 241, 0.3);
}

.viewer-btn svg {
    width: 16px;
    height: 16px;
}

.viewer-btn.primary {
    background: linear-gradient(135deg, #6366f1, #a855f7);
    border: none;
    color: white;
}

.viewer-btn.primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.viewer-canvas-container {
    position: relative;
    width: 100%;
    height: 500px;
    background: #000;
    border-left: 1px solid var(--card-border);
    border-right: 1px solid var(--card-border);
    overflow: hidden;
}

.viewer-canvas-container canvas {
    width: 100% !important;
    height: 100% !important;
}

.viewer-controls-hint {
    position: absolute;
    bottom: 1rem;
    left: 50%;
    transform: translateX(-50%);
    padding: 0.5rem 1rem;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(10px);
    border-radius: 8px;
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.7);
    pointer-events: none;
    transition: opacity 0.3s ease;
}

.viewer-footer {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 0 0 16px 16px;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.viewer-footer span {
    font-size: 0.75rem;
    color: var(--text-dim);
}

.viewer-footer a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.2s ease;
}

.viewer-footer a:hover {
    color: var(--text-primary);
    text-decoration: underline;
}

.back-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    font-size: 0.875rem;
    font-weight: 500;
    font-family: inherit;
    color: var(--text-muted);
    background: transparent;
    border: 1px solid var(--card-border);
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.2s ease;
    margin-bottom: 1rem;
}

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

.back-btn svg {
    width: 18px;
    height: 18px;
}

/* Hide card when viewing */
.card.hidden {
    display: none;
}

.header.minimized {
    margin-bottom: 1rem;
}

.header.minimized .logo {
    font-size: 2rem;
}

.header.minimized .tagline {
    display: none;
}