:root {
    /* Light Theme Colors */
    --bg-color: #f8fafc;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --panel-bg: rgba(255, 255, 255, 0.7);
    --panel-border: rgba(255, 255, 255, 0.6);
    --input-bg: rgba(255, 255, 255, 0.9);
    --input-border: #cbd5e1;
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --error: #ef4444;
    --success: #10b981;
    --shadow: 0 20px 40px -15px rgba(0,0,0,0.05);
    --blob-1: rgba(59, 130, 246, 0.4);
    --blob-2: rgba(147, 51, 234, 0.3);
    --chart-text: #64748b;
    --chart-grid: #e2e8f0;
}

[data-theme="dark"] {
    --bg-color: #0f172a;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --panel-bg: rgba(30, 41, 59, 0.6);
    --panel-border: rgba(255, 255, 255, 0.08);
    --input-bg: rgba(15, 23, 42, 0.8);
    --input-border: #334155;
    --primary: #3b82f6;
    --primary-hover: #60a5fa;
    --error: #fca5a5;
    --success: #34d399;
    --shadow: 0 20px 40px -15px rgba(0,0,0,0.5);
    --blob-1: rgba(59, 130, 246, 0.15);
    --blob-2: rgba(147, 51, 234, 0.15);
    --chart-text: #94a3b8;
    --chart-grid: #334155;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
    transition: background-color 0.4s ease, color 0.4s ease, border-color 0.4s ease;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    position: relative;
    overflow-x: hidden;
}

/* Background Blobs for Modern UI */
.background-elements {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    overflow: hidden;
    pointer-events: none;
}

.blob {
    position: absolute;
    filter: blur(90px);
    border-radius: 50%;
    animation: float 12s infinite ease-in-out alternate;
}

.blob-1 {
    top: -10%;
    left: -10%;
    width: 50vw;
    height: 50vw;
    background: var(--blob-1);
}

.blob-2 {
    bottom: -10%;
    right: -10%;
    width: 40vw;
    height: 40vw;
    background: var(--blob-2);
    animation-delay: -6s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(6%, 6%) scale(1.1); }
}

.app-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 3rem 2rem;
}

/* Header */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 3rem;
    animation: fadeDown 0.6s ease;
}

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

h1 {
    font-size: 2.75rem;
    font-weight: 800;
    letter-spacing: -1px;
}

.highlight {
    color: var(--primary);
}

.tagline {
    color: var(--text-secondary);
    font-size: 1.125rem;
    margin-top: 0.5rem;
    font-weight: 400;
}

#theme-toggle {
    background: var(--panel-bg);
    border: 1px solid var(--panel-border);
    color: var(--text-primary);
    width: 50px;
    height: 50px;
    border-radius: 14px;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    backdrop-filter: blur(12px);
    box-shadow: var(--shadow);
}

#theme-toggle:hover {
    transform: translateY(-2px);
    border-color: var(--primary);
}

/* Layout */
.grid-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem;
    animation: fadeIn 0.8s ease backwards;
    animation-delay: 0.2s;
}

@media (max-width: 900px) {
    .grid-container {
        grid-template-columns: 1fr;
    }
}

/* Panels (Glassmorphism) */
.glass-panel {
    background: var(--panel-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--panel-border);
    border-radius: 24px;
    padding: 2.5rem;
    box-shadow: var(--shadow);
}

h2 {
    margin-bottom: 2rem;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

/* Forms */
.input-group {
    margin-bottom: 1.5rem;
    display: flex;
    flex-direction: column;
}

.row {
    display: flex;
    gap: 1.5rem;
}

.half {
    flex: 1;
}

label {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

input, select {
    background: var(--input-bg);
    border: 1px solid var(--input-border);
    color: var(--text-primary);
    padding: 1rem 1.25rem;
    border-radius: 12px;
    font-size: 1rem;
    outline: none;
}

input:focus, select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.15);
}

/* Button */
#predict-btn {
    width: 100%;
    background: var(--primary);
    color: white;
    border: none;
    padding: 1.125rem;
    border-radius: 14px;
    font-size: 1.125rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 10px 25px -5px rgba(59, 130, 246, 0.4);
    margin-top: 1rem;
}

#predict-btn:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 15px 30px -5px rgba(59, 130, 246, 0.5);
}

#predict-btn:active {
    transform: translateY(0);
}

/* Loading Spinner */
.spinner {
    display: none;
    width: 24px;
    height: 24px;
    border: 3px solid rgba(255,255,255,0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

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

#predict-btn.loading .btn-text { display: none; }
#predict-btn.loading .spinner { display: block; }
#predict-btn.loading { opacity: 0.8; cursor: not-allowed; }

/* Result Area */
#result-container {
    margin-top: 2rem;
    padding: 2rem;
    background: rgba(16, 185, 129, 0.05);
    border: 1px solid rgba(16, 185, 129, 0.2);
    border-radius: 16px;
    text-align: center;
    animation: zoomIn 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

@keyframes zoomIn {
    from { opacity: 0; transform: scale(0.95); }
    to { opacity: 1; transform: scale(1); }
}

.price-display {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--success);
    margin: 0.5rem 0;
    font-feature-settings: "tnum";
    letter-spacing: -1px;
}

.confidence-text {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* Utility */
.hidden {
    display: none !important;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}

#error-alert {
    margin-top: 1.5rem;
    padding: 1rem;
    background: rgba(239, 68, 68, 0.1);
    color: var(--error);
    border: 1px solid rgba(239, 68, 68, 0.2);
    border-radius: 12px;
    font-size: 0.9rem;
    text-align: center;
    animation: fadeIn 0.3s;
}

/* Charts */
.chart-container {
    position: relative;
    height: 240px;
    width: 100%;
}