:root {
    /* Base Colors - Dark Theme (Default) */
    --bg-base: #09090b;
    --bg-surface: #18181b;
    --bg-elevated: #27272a;
    
    --text-primary: #f4f4f5;
    --text-secondary: #a1a1aa;
    --text-muted: #71717a;
    
    --border-subtle: rgba(255, 255, 255, 0.1);
    
    --primary: #8b5cf6;
    --primary-hover: #7c3aed;
    --primary-light: rgba(139, 92, 246, 0.15);
    
    --accent-red: #f43f5e;
    --accent-blue: #0ea5e9;
    --accent-green: #10b981;
    --accent-orange: #f59e0b;
    --danger-color: #ef4444;

    --glass-bg: rgba(24, 24, 27, 0.7);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-pill: 9999px;
    
    --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="light"] {
    --bg-base: #f4f4f5;
    --bg-surface: #ffffff;
    --bg-elevated: #f8fafc;
    
    --text-primary: #09090b;
    --text-secondary: #52525b;
    --text-muted: #a1a1aa;
    
    --border-subtle: rgba(0, 0, 0, 0.1);
    
    --glass-bg: rgba(255, 255, 255, 0.8);
    --glass-border: rgba(0, 0, 0, 0.05);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.05);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Outfit', -apple-system, sans-serif;
}

body {
    background-color: var(--bg-base);
    color: var(--text-primary);
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
    transition: background-color var(--transition), color var(--transition);
}

/* Layout */
.app-layout {
    display: flex;
    height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 280px;
    background-color: var(--bg-surface);
    border-right: 1px solid var(--border-subtle);
    padding: 32px 24px;
    display: flex;
    flex-direction: column;
    z-index: 10;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 40px;
    color: var(--primary);
}

.brand h1 {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text-primary);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 20px;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: var(--transition);
    border: none;
}

.btn-block {
    width: 100%;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-hover));
    color: white;
    box-shadow: 0 4px 12px rgba(139, 92, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(139, 92, 246, 0.4);
}

.btn-secondary {
    background-color: var(--bg-elevated);
    color: var(--text-primary);
    border: 1px solid var(--border-subtle);
}

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

.icon-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 8px;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.icon-btn:hover {
    background-color: var(--bg-elevated);
    color: var(--text-primary);
}

.add-btn {
    margin-bottom: 32px;
}

.nav-menu {
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex-grow: 1;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 16px;
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
    background: transparent;
    border: none;
    width: 100%;
    font-size: 1rem;
    text-align: left;
}

.nav-item:hover {
    background-color: var(--bg-elevated);
    color: var(--text-primary);
}

.nav-item.active {
    background-color: var(--primary-light);
    color: var(--primary);
}

.sidebar-bottom {
    margin-top: auto;
    padding-top: 24px;
    border-top: 1px solid var(--border-subtle);
}

/* Main Content Area */
.content-area {
    flex-grow: 1;
    overflow-y: auto;
    padding: 48px;
    position: relative;
}

.view {
    display: none;
    animation: fadeUp 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    max-width: 1000px;
    margin: 0 auto;
}

.view.active-view {
    display: block;
}

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

.section-header {
    margin-bottom: 32px;
}

.section-header h2 {
    font-size: 2.25rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 4px;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.header-split {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
}

/* Base Components Output */
.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--glass-shadow);
}

/* Hero Card (Next Birthday) */
.hero-card {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 40px;
    margin-bottom: 40px;
    position: relative;
    overflow: hidden;
}

.hero-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at top right, var(--primary-light), transparent 50%);
    z-index: 0;
    pointer-events: none;
}

.hero-content, .hero-visual {
    position: relative;
    z-index: 1;
}

.hero-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.badge {
    background: var(--primary);
    color: white;
    padding: 6px 12px;
    border-radius: var(--radius-pill);
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.hero-date {
    color: var(--text-secondary);
    font-weight: 500;
}

.hero-card h3 {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    margin-bottom: 8px;
    background: linear-gradient(135deg, var(--text-primary), var(--text-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-details {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 32px;
}

.highlight {
    color: var(--text-primary);
    font-weight: 600;
}

/* Circular Chart */
.countdown-circle {
    position: relative;
    width: 160px;
    height: 160px;
}

.circular-chart {
    display: block;
    margin: 0 auto;
    max-width: 100%;
    max-height: 250px;
}

.circle-bg {
    fill: none;
    stroke: var(--border-subtle);
    stroke-width: 2.5;
}

.circle {
    fill: none;
    stroke-width: 2.5;
    stroke-linecap: round;
    animation: progress 1s ease-out forwards;
}

/* Dynamic stroke colors set by JS */
.circle.danger { stroke: var(--accent-red); }
.circle.warning { stroke: var(--accent-orange); }
.circle.success { stroke: var(--primary); }

@keyframes progress {
    0% { stroke-dasharray: 0 100; }
}

.countdown-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    display: flex;
    flex-direction: column;
}

.countdown-text .number {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-primary);
    line-height: 1.1;
}

.countdown-text .label {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
}

/* Upcoming List */
.upcoming-list {
    display: grid;
    gap: 16px;
}

.person-card {
    background-color: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 24px;
    transition: var(--transition);
    cursor: pointer;
}

.person-card:hover {
    border-color: var(--primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

.avatar {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-pill);
    background: linear-gradient(135deg, var(--bg-elevated), var(--border-subtle));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.person-info {
    flex-grow: 1;
}

.person-info h4 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.category-tag {
    font-size: 0.8rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.person-meta {
    text-align: right;
}

.days-left {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.days-left.urgent { color: var(--accent-red); }

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

/* Search Box */
.search-box {
    position: relative;
    width: 300px;
}

.search-box i {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

.search-box input {
    width: 100%;
    background-color: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    color: var(--text-primary);
    padding: 12px 16px 12px 48px;
    border-radius: var(--radius-pill);
    font-size: 1rem;
    transition: var(--transition);
}

.search-box input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

/* People Grid */
.people-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}

/* Gifts View */
.gifts-container {
    display: flex;
    gap: 32px;
    height: calc(100vh - 200px);
}

.gift-sidebar {
    width: 250px;
    background-color: var(--bg-surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-subtle);
    padding: 24px;
    display: flex;
    flex-direction: column;
}

.gift-sidebar h3 {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.gift-people-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
    overflow-y: auto;
}

.gift-person-item {
    padding: 12px 16px;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--text-secondary);
}

.gift-person-item:hover {
    background-color: var(--bg-elevated);
}

.gift-person-item.active {
    background-color: var(--primary-light);
    color: var(--primary);
    font-weight: 500;
}

.gift-main {
    flex-grow: 1;
    padding: 40px;
    display: flex;
    flex-direction: column;
    overflow-y: auto;
}

.gift-header {
    margin-bottom: 32px;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--border-subtle);
}

.gift-person-info {
    display: flex;
    align-items: center;
    gap: 16px;
}

.gift-person-info h3 {
    font-size: 1.75rem;
}

.add-gift-form {
    display: flex;
    gap: 16px;
    margin-bottom: 32px;
}

.add-gift-form input[type="text"] {
    flex-grow: 1;
    background-color: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    color: var(--text-primary);
    padding: 14px 20px;
    border-radius: var(--radius-md);
    font-size: 1rem;
    transition: var(--transition);
}

.price-input-wrapper {
    position: relative;
    width: 120px;
}

.price-input-wrapper .currency-symbol {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

.price-input-wrapper input {
    width: 100%;
    background-color: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    color: var(--text-primary);
    padding: 14px 16px 14px 32px;
    border-radius: var(--radius-md);
    font-size: 1rem;
}

.add-gift-form input:focus {
    outline: none;
    border-color: var(--primary);
}

.gift-ideas-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.gift-idea-card {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
    background-color: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    animation: fadeUp 0.3s ease-out;
}

.gift-idea-info {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.gift-idea-title {
    font-size: 1.1rem;
    font-weight: 500;
}

.gift-idea-price {
    color: var(--accent-green);
    font-weight: 600;
}

.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: var(--text-muted);
    text-align: center;
}

.empty-state svg {
    width: 64px;
    height: 64px;
    margin-bottom: 24px;
    opacity: 0.5;
}

/* Modals */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 100;
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
}

.modal-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.modal {
    width: 100%;
    max-width: 500px;
    background-color: var(--bg-surface);
    transform: scale(0.95) translateY(20px);
    transition: var(--transition);
}

.modal-overlay.active .modal {
    transform: scale(1) translateY(0);
}

.modal-header {
    padding: 24px 32px;
    border-bottom: 1px solid var(--border-subtle);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-body {
    padding: 32px;
}

.form-group {
    margin-bottom: 24px;
}

.form-row {
    display: flex;
    gap: 20px;
}

.form-row .form-group {
    flex: 1;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-secondary);
}

.form-group input[type="text"],
.form-group input[type="date"],
.form-group select {
    width: 100%;
    padding: 14px 16px;
    background-color: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.toggle-switch {
    position: relative;
    display: inline-block;
    width: 52px;
    height: 28px;
    margin-top: 10px;
}

.toggle-switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    transition: .4s;
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 20px;
    width: 20px;
    left: 3px;
    bottom: 3px;
    background-color: var(--text-muted);
    transition: .4s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: var(--primary);
    border-color: var(--primary);
}

input:checked + .slider:before {
    transform: translateX(24px);
    background-color: white;
}

.modal-actions {
    display: flex;
    gap: 12px;
    margin-top: 32px;
    padding-top: 24px;
    border-top: 1px solid var(--border-subtle);
}

.spacer {
    flex-grow: 1;
}

/* Animations & Responsive */
@media (max-width: 900px) {
    .app-layout {
        flex-direction: column;
    }
    
    .sidebar {
        width: 100%;
        padding: 20px;
        flex-direction: row;
        align-items: center;
        border-right: none;
        border-bottom: 1px solid var(--border-subtle);
        height: auto;
        overflow-x: auto;
    }
    
    .brand { margin-bottom: 0; margin-right: 24px; }
    .add-btn { width: auto; margin-bottom: 0; margin-right: 24px; }
    
    .nav-menu {
        flex-direction: row;
    }
    
    .nav-item { width: auto; white-space: nowrap; }
    .sidebar-bottom { margin-top: 0; border-top: none; padding-top: 0; margin-left: 16px; }
    
    .hero-card {
        flex-direction: column;
        text-align: center;
        gap: 32px;
    }
    
    .hero-meta { justify-content: center; }
    
    .gifts-container {
        flex-direction: column;
        height: auto;
    }
    
    .gift-sidebar { width: 100%; max-height: 200px; }
}

@media (max-width: 600px) {
    .content-area { padding: 24px; }
    .header-split { flex-direction: column; align-items: flex-start; gap: 16px; }
    .search-box { width: 100%; }
}