/* ============================================================
   DR Diagnostic Platform — Material Design 3 Premium Stylesheet
   ============================================================ */

:root {
    /* Primary Palette — Deep Indigo / Teal */
    --md-primary: #1a237e;
    --md-primary-light: #534bae;
    --md-primary-dark: #000051;
    --md-secondary: #00897b;
    --md-secondary-light: #4ebaaa;
    --md-secondary-dark: #005b4f;
    --md-on-primary: #ffffff;

    /* Surface & Background */
    --md-surface: #ffffff;
    --md-surface-variant: #f5f6fa;
    --md-surface-elevated: #ffffff;
    --md-background: #f0f2f5;
    --md-on-surface: #1c1b1f;
    --md-on-surface-variant: #49454f;
    --md-outline: #dde1e6;

    /* Elevation Shadows */
    --shadow-1: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-2: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
    --shadow-3: 0 10px 25px rgba(0,0,0,0.08), 0 4px 10px rgba(0,0,0,0.05);
    --shadow-4: 0 20px 40px rgba(0,0,0,0.1), 0 8px 16px rgba(0,0,0,0.06);

    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;

    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-standard: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-emphasis: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-primary);
    background: var(--md-background);
    color: var(--md-on-surface);
    line-height: 1.6;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ============================================================
   Header
   ============================================================ */
.app-header {
    background: linear-gradient(135deg, var(--md-primary) 0%, var(--md-primary-light) 100%);
    color: var(--md-on-primary);
    padding: 0 24px;
    box-shadow: var(--shadow-3);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 0;
    gap: 16px;
}

.header-brand {
    display: flex;
    align-items: center;
    gap: 16px;
}

.header-icon {
    font-size: 36px;
    opacity: 0.95;
}

.header-title {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: -0.3px;
    line-height: 1.2;
}

.header-subtitle {
    font-size: 13px;
    font-weight: 400;
    opacity: 0.8;
    margin-top: 2px;
}

.header-badge {
    display: flex;
    gap: 8px;
    flex-shrink: 0;
}

.badge-version, .badge-model {
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.3px;
}

.badge-version {
    background: rgba(255,255,255,0.2);
    backdrop-filter: blur(10px);
}

.badge-model {
    background: var(--md-secondary);
    color: #fff;
}

/* ============================================================
   Main Content
   ============================================================ */
.app-main {
    max-width: 1000px;
    margin: 0 auto;
    padding: 32px 24px;
}

/* ============================================================
   Upload Section
   ============================================================ */
.upload-card {
    background: var(--md-surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-2);
    overflow: hidden;
    transition: box-shadow var(--transition-standard);
}

.upload-card:hover {
    box-shadow: var(--shadow-3);
}

.upload-zone {
    padding: 48px 32px;
    border: 2px dashed var(--md-outline);
    border-radius: var(--radius-lg);
    margin: 24px;
    cursor: pointer;
    transition: all var(--transition-standard);
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 300px;
}

.upload-zone:hover, .upload-zone.drag-over {
    border-color: var(--md-primary);
    background: rgba(26, 35, 126, 0.03);
}

.upload-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 8px;
}

.upload-icon {
    font-size: 64px;
    color: var(--md-primary);
    opacity: 0.6;
    margin-bottom: 8px;
}

.upload-title {
    font-size: 22px;
    font-weight: 600;
    color: var(--md-on-surface);
}

.upload-desc {
    font-size: 14px;
    color: var(--md-on-surface-variant);
    max-width: 360px;
}

.upload-formats {
    font-size: 12px;
    color: var(--md-on-surface-variant);
    opacity: 0.7;
    margin-top: 4px;
}

.upload-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    background: var(--md-primary);
    color: var(--md-on-primary);
    border: none;
    border-radius: var(--radius-xl);
    font-family: var(--font-primary);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    margin-top: 16px;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-1);
}

.upload-btn:hover {
    background: var(--md-primary-light);
    box-shadow: var(--shadow-2);
    transform: translateY(-1px);
}

.upload-preview {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.upload-preview img {
    max-width: 100%;
    max-height: 400px;
    border-radius: var(--radius-md);
    object-fit: contain;
}

.remove-btn {
    position: absolute;
    top: -8px;
    right: -8px;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: #ef5350;
    color: #fff;
    border: 3px solid var(--md-surface);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-2);
    transition: all var(--transition-fast);
}

.remove-btn:hover {
    background: #d32f2f;
    transform: scale(1.1);
}

.remove-btn .material-icons-round {
    font-size: 18px;
}

.analyze-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    width: calc(100% - 48px);
    margin: 0 24px 24px;
    padding: 16px;
    background: linear-gradient(135deg, var(--md-secondary), var(--md-secondary-dark));
    color: #fff;
    border: none;
    border-radius: var(--radius-md);
    font-family: var(--font-primary);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-standard);
    box-shadow: var(--shadow-2);
}

.analyze-btn:hover:not(:disabled) {
    box-shadow: var(--shadow-3);
    transform: translateY(-1px);
}

.analyze-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none;
}

/* ============================================================
   Loading Section
   ============================================================ */
.loading-section {
    display: flex;
    justify-content: center;
    padding: 48px 0;
}

.loading-card {
    background: var(--md-surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-3);
    padding: 48px 64px;
    text-align: center;
}

.loading-spinner {
    width: 56px;
    height: 56px;
    border: 4px solid var(--md-outline);
    border-top-color: var(--md-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 24px;
}

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

.loading-title {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 8px;
}

.loading-desc {
    font-size: 14px;
    color: var(--md-on-surface-variant);
    margin-bottom: 32px;
}

.loading-steps {
    display: flex;
    gap: 24px;
    justify-content: center;
}

.loading-step {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    font-size: 12px;
    font-weight: 500;
    color: var(--md-outline);
    transition: color var(--transition-standard);
}

.loading-step .material-icons-round {
    font-size: 24px;
}

.loading-step.active {
    color: var(--md-primary);
}

/* ============================================================
   Results Section
   ============================================================ */
.results-section {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.fade-in {
    animation: fadeInUp 0.6s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Primary Result */
.result-primary {
    background: var(--md-surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-3);
    padding: 32px;
    display: flex;
    align-items: center;
    gap: 32px;
}

.severity-indicator {
    flex-shrink: 0;
    width: 200px;
    padding: 24px;
    border-radius: var(--radius-lg);
    border: 3px solid;
    text-align: center;
    transition: all var(--transition-emphasis);
}

.severity-grade {
    font-size: 48px;
    font-weight: 800;
    line-height: 1;
}

.severity-label {
    font-size: 18px;
    font-weight: 600;
    margin-top: 8px;
}

.severity-risk {
    font-size: 13px;
    font-weight: 600;
    margin-top: 4px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.confidence-section {
    flex: 1;
}

.confidence-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--md-on-surface-variant);
    margin-bottom: 12px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.confidence-bar-container {
    height: 12px;
    background: var(--md-surface-variant);
    border-radius: 6px;
    overflow: hidden;
}

.confidence-bar {
    height: 100%;
    border-radius: 6px;
    width: 0;
    transition: width 1s cubic-bezier(0.4, 0, 0.2, 1);
}

.confidence-value {
    display: block;
    font-size: 28px;
    font-weight: 700;
    margin-top: 12px;
    color: var(--md-on-surface);
    font-family: var(--font-mono);
}

/* Metrics Grid */
.metrics-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.metric-card {
    background: var(--md-surface);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-1);
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 16px;
    transition: box-shadow var(--transition-fast);
}

.metric-card:hover {
    box-shadow: var(--shadow-2);
}

.metric-icon {
    font-size: 28px;
    color: var(--md-secondary);
    background: rgba(0, 137, 123, 0.08);
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
}

.metric-value {
    font-size: 20px;
    font-weight: 700;
    font-family: var(--font-mono);
    color: var(--md-on-surface);
    display: block;
}

.metric-label {
    font-size: 12px;
    color: var(--md-on-surface-variant);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.3px;
}

/* Probabilities Card */
.probabilities-card {
    background: var(--md-surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-2);
    padding: 28px;
}

.card-title {
    font-size: 16px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 20px;
    color: var(--md-on-surface);
}

.card-title .material-icons-round {
    font-size: 20px;
    color: var(--md-primary);
}

.prob-row {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
}

.prob-label {
    width: 130px;
    font-size: 13px;
    font-weight: 500;
    color: var(--md-on-surface-variant);
    flex-shrink: 0;
}

.prob-track {
    flex: 1;
    height: 10px;
    background: var(--md-surface-variant);
    border-radius: 5px;
    overflow: hidden;
}

.prob-fill {
    height: 100%;
    border-radius: 5px;
    transition: width 1s cubic-bezier(0.4, 0, 0.2, 1);
}

.prob-value {
    width: 60px;
    text-align: right;
    font-size: 13px;
    font-weight: 600;
    font-family: var(--font-mono);
    color: var(--md-on-surface);
    flex-shrink: 0;
}

/* Visual Cards */
.visuals-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.visual-card {
    background: var(--md-surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-2);
    padding: 24px;
}

.visual-container {
    background: #0a0a0a;
    border-radius: var(--radius-md);
    padding: 8px;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 250px;
}

.visual-container img {
    max-width: 100%;
    max-height: 350px;
    border-radius: var(--radius-sm);
    object-fit: contain;
}

.no-gradcam {
    color: #666;
    font-size: 14px;
    font-style: italic;
    text-align: center;
    padding: 40px;
}

/* Disclaimer */
.disclaimer-card {
    background: linear-gradient(135deg, #fff3e0, #ffe0b2);
    border: 1px solid #ffcc02;
    border-radius: var(--radius-md);
    padding: 20px 24px;
    display: flex;
    gap: 16px;
    align-items: flex-start;
}

.disclaimer-icon {
    font-size: 28px;
    color: #e65100;
    flex-shrink: 0;
    margin-top: 2px;
}

.disclaimer-title {
    font-size: 14px;
    font-weight: 700;
    color: #bf360c;
    margin-bottom: 4px;
    text-transform: uppercase;
    letter-spacing: 0.3px;
}

.disclaimer-text {
    font-size: 13px;
    color: #4e342e;
    line-height: 1.5;
}

/* New Analysis Button */
.new-analysis-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    width: 100%;
    padding: 16px;
    background: var(--md-primary);
    color: var(--md-on-primary);
    border: none;
    border-radius: var(--radius-md);
    font-family: var(--font-primary);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-standard);
    box-shadow: var(--shadow-2);
}

.new-analysis-btn:hover {
    background: var(--md-primary-light);
    box-shadow: var(--shadow-3);
    transform: translateY(-1px);
}

/* ============================================================
   Footer
   ============================================================ */
.app-footer {
    text-align: center;
    padding: 32px 24px 40px;
    color: var(--md-on-surface-variant);
    font-size: 13px;
}

.footer-meta {
    margin-top: 4px;
    font-size: 12px;
    opacity: 0.6;
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        text-align: center;
    }

    .header-brand {
        flex-direction: column;
        gap: 8px;
    }

    .result-primary {
        flex-direction: column;
        text-align: center;
    }

    .severity-indicator {
        width: 100%;
        max-width: 240px;
    }

    .metrics-grid {
        grid-template-columns: 1fr;
    }

    .visuals-grid {
        grid-template-columns: 1fr;
    }

    .loading-steps {
        flex-direction: column;
        gap: 12px;
    }

    .upload-zone {
        padding: 32px 16px;
        margin: 16px;
    }

    .analyze-btn {
        margin: 0 16px 16px;
        width: calc(100% - 32px);
    }
}