/* Nexus Calendar - Design System */
:root {
    /* Colors - Indigo Ink Palette */
    --color-bg-primary: #ffffff;
    --color-bg-secondary: #f8f7fc;
    --color-bg-tertiary: #f0eef5;
    --color-bg-elevated: #ffffff;
    
    --color-text-primary: #1b0a3c;
    --color-text-secondary: #5a4a6e;
    --color-text-tertiary: #8b7a9e;
    --color-text-inverse: #ffffff;
    
    --color-border: #e8e0f0;
    --color-border-hover: #d4c8e0;
    
    --color-accent: #7b68ee;
    --color-accent-hover: #6b5ce0;
    --color-accent-light: #e8e0f0;
    
    --color-calendar-personal: #6366f1;
    --color-calendar-work: #10b981;
    --color-calendar-family: #f59e0b;
    --color-calendar-birthdays: #ec4899;
    
    /* Typography */
    --font-display: 'Space Grotesk', sans-serif;
    --font-body: 'Plus Jakarta Sans', sans-serif;
    
    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(27, 10, 60, 0.05);
    --shadow-md: 0 4px 12px rgba(27, 10, 60, 0.08);
    --shadow-lg: 0 8px 24px rgba(27, 10, 60, 0.12);
    --shadow-xl: 0 16px 48px rgba(27, 10, 60, 0.16);
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;
}

/* Dark Mode */
[data-theme="dark"] {
    --color-bg-primary: #0d0a14;
    --color-bg-secondary: #1a1425;
    --color-bg-tertiary: #241d33;
    --color-bg-elevated: #1a1425;
    
    --color-text-primary: #f5f0ff;
    --color-text-secondary: #c4b8d9;
    --color-text-tertiary: #8b7a9e;
    
    --color-border: #2d2440;
    --color-border-hover: #3d3255;
    
    --color-accent: #9b8af5;
    --color-accent-hover: #a89aff;
    --color-accent-light: #2d2440;
}

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

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    background: var(--color-bg-primary);
    color: var(--color-text-primary);
    line-height: 1.5;
    min-height: 100vh;
    overflow: hidden;
}

/* App Container */
.app-container {
    display: flex;
    height: 100vh;
    overflow: hidden;
}

/* Sidebar */
.sidebar {
    width: 280px;
    background: var(--color-bg-secondary);
    border-right: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
    padding: var(--space-lg);
    overflow-y: auto;
}

.sidebar-header {
    margin-bottom: var(--space-xl);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
}

.logo-icon {
    width: 32px;
    height: 32px;
    color: var(--color-accent);
}

.logo-text {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-text-primary);
}

.btn-create {
    width: 100%;
    justify-content: center;
    gap: var(--space-sm);
}

/* Mini Calendar */
.mini-calendar {
    margin-bottom: var(--space-xl);
}

.mini-calendar-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-md);
}

.mini-calendar-month {
    font-family: var(--font-display);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-text-primary);
}

.nav-btn {
    width: 28px;
    height: 28px;
    border: none;
    background: transparent;
    color: var(--color-text-secondary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

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

.nav-btn .icon {
    width: 16px;
    height: 16px;
}

.mini-calendar-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 2px;
}

.mini-calendar-day {
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    color: var(--color-text-secondary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.mini-calendar-day:hover {
    background: var(--color-bg-tertiary);
}

.mini-calendar-day.other-month {
    color: var(--color-text-tertiary);
}

.mini-calendar-day.today {
    background: var(--color-accent);
    color: white;
    font-weight: 600;
}

.mini-calendar-day.selected {
    background: var(--color-accent-light);
    color: var(--color-accent);
    font-weight: 600;
}

/* My Calendars */
.my-calendars {
    margin-bottom: var(--space-xl);
}

.section-title {
    font-family: var(--font-display);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-md);
}

.calendar-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.calendar-item {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: background var(--transition-fast);
}

.calendar-item:hover {
    background: var(--color-bg-tertiary);
}

.calendar-checkbox {
    width: 16px;
    height: 16px;
    accent-color: var(--color-accent);
}

.calendar-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    flex-shrink: 0;
}

.calendar-name {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
}

/* Upcoming Events */
.upcoming-events {
    flex: 1;
}

.event-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.upcoming-event {
    display: flex;
    gap: var(--space-sm);
    padding: var(--space-sm);
    border-radius: var(--radius-md);
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.upcoming-event:hover {
    border-color: var(--color-border-hover);
    box-shadow: var(--shadow-sm);
}

.upcoming-event-time {
    font-size: 0.75rem;
    color: var(--color-text-tertiary);
    white-space: nowrap;
}

.upcoming-event-title {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-primary);
    margin-bottom: 2px;
}

.upcoming-event-calendar {
    font-size: 0.75rem;
    color: var(--color-text-tertiary);
}

/* Main Content */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

/* Header */
.main-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-lg) var(--space-xl);
    border-bottom: 1px solid var(--color-border);
    background: var(--color-bg-primary);
}

.header-left {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.current-date {
    font-family: var(--font-display);
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--color-text-primary);
    min-width: 180px;
}

.view-controls {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.view-switcher {
    display: flex;
    background: var(--color-bg-secondary);
    border-radius: var(--radius-md);
    padding: 4px;
}

.view-btn {
    padding: var(--space-sm) var(--space-md);
    border: none;
    background: transparent;
    color: var(--color-text-secondary);
    font-family: var(--font-body);
    font-size: 0.875rem;
    font-weight: 500;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.view-btn:hover {
    color: var(--color-text-primary);
}

.view-btn.active {
    background: var(--color-bg-elevated);
    color: var(--color-text-primary);
    box-shadow: var(--shadow-sm);
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.search-box {
    position: relative;
    display: flex;
    align-items: center;
}

.search-icon {
    position: absolute;
    left: var(--space-md);
    width: 18px;
    height: 18px;
    color: var(--color-text-tertiary);
}

.search-box input {
    width: 240px;
    padding: var(--space-sm) var(--space-md) var(--space-sm) 2.5rem;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    background: var(--color-bg-secondary);
    color: var(--color-text-primary);
    font-family: var(--font-body);
    font-size: 0.875rem;
    transition: all var(--transition-fast);
}

.search-box input:focus {
    outline: none;
    border-color: var(--color-accent);
    background: var(--color-bg-elevated);
}

.search-box input::placeholder {
    color: var(--color-text-tertiary);
}

.user-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    overflow: hidden;
    border: 2px solid var(--color-border);
}

.user-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* Calendar Container */
.calendar-container {
    flex: 1;
    overflow: auto;
    padding: var(--space-lg) var(--space-xl);
}

.calendar-view {
    display: none;
    height: 100%;
}

.calendar-view.active {
    display: flex;
    flex-direction: column;
}

/* Month View */
.month-view {
    height: 100%;
}

.calendar-grid-header {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 1px;
    margin-bottom: var(--space-sm);
}

.day-header {
    text-align: center;
    padding: var(--space-sm);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-tertiary);
}

.calendar-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    grid-template-rows: repeat(6, 1fr);
    gap: 1px;
    background: var(--color-border);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    overflow: hidden;
    flex: 1;
}

.calendar-day {
    background: var(--color-bg-primary);
    padding: var(--space-sm);
    min-height: 120px;
    cursor: pointer;
    transition: background var(--transition-fast);
    position: relative;
}

.calendar-day:hover {
    background: var(--color-bg-secondary);
}

.calendar-day.other-month {
    background: var(--color-bg-secondary);
    color: var(--color-text-tertiary);
}

.calendar-day.today {
    background: var(--color-accent-light);
}

.calendar-day.today .day-number {
    background: var(--color-accent);
    color: white;
}

.calendar-day.selected {
    box-shadow: inset 0 0 0 2px var(--color-accent);
}

.day-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    font-size: 0.875rem;
    font-weight: 500;
    border-radius: 50%;
    margin-bottom: var(--space-sm);
}

.day-events {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.day-event {
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    cursor: pointer;
    transition: transform var(--transition-fast);
}

.day-event:hover {
    transform: translateX(2px);
}

.day-event.personal { background: rgba(99, 102, 241, 0.15); color: var(--color-calendar-personal); }
.day-event.work { background: rgba(16, 185, 129, 0.15); color: var(--color-calendar-work); }
.day-event.family { background: rgba(245, 158, 11, 0.15); color: var(--color-calendar-family); }
.day-event.birthdays { background: rgba(236, 72, 153, 0.15); color: var(--color-calendar-birthdays); }

/* Week View */
.week-view {
    height: 100%;
}

.week-header {
    display: grid;
    grid-template-columns: 60px repeat(7, 1fr);
    gap: 1px;
    margin-bottom: var(--space-sm);
}

.week-day-header {
    text-align: center;
    padding: var(--space-md);
}

.week-day-header .day-name {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-tertiary);
    margin-bottom: 4px;
}

.week-day-header .day-number {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-text-primary);
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto;
}

.week-day-header.today .day-number {
    background: var(--color-accent);
    color: white;
    border-radius: 50%;
}

.week-grid {
    display: grid;
    grid-template-columns: 60px repeat(7, 1fr);
    gap: 1px;
    background: var(--color-border);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    overflow: hidden;
    flex: 1;
    overflow-y: auto;
}

.time-slot {
    background: var(--color-bg-primary);
    border-bottom: 1px solid var(--color-border);
    height: 60px;
    position: relative;
}

.time-label {
    position: sticky;
    left: 0;
    background: var(--color-bg-secondary);
    display: flex;
    align-items: flex-start;
    justify-content: flex-end;
    padding-right: var(--space-sm);
    font-size: 0.75rem;
    color: var(--color-text-tertiary);
    height: 60px;
}

.time-label span {
    transform: translateY(-50%);
}

.week-day-column {
    background: var(--color-bg-primary);
    position: relative;
    min-height: 60px;
}

.week-day-column:hover {
    background: var(--color-bg-secondary);
}

.week-event {
    position: absolute;
    left: 2px;
    right: 2px;
    padding: var(--space-sm);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    cursor: pointer;
    overflow: hidden;
    border-left: 3px solid;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.week-event:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
    z-index: 10;
}

.week-event.personal { background: rgba(99, 102, 241, 0.1); border-left-color: var(--color-calendar-personal); }
.week-event.work { background: rgba(16, 185, 129, 0.1); border-left-color: var(--color-calendar-work); }
.week-event.family { background: rgba(245, 158, 11, 0.1); border-left-color: var(--color-calendar-family); }
.week-event.birthdays { background: rgba(236, 72, 153, 0.1); border-left-color: var(--color-calendar-birthdays); }

/* Day View */
.day-view {
    height: 100%;
}

.day-header {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-lg);
    border-bottom: 1px solid var(--color-border);
}

.day-header-content {
    text-align: center;
}

.day-header .day-name {
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-xs);
}

.day-header .day-number {
    font-family: var(--font-display);
    font-size: 3rem;
    font-weight: 700;
    color: var(--color-text-primary);
}

.day-header.today .day-number {
    color: var(--color-accent);
}

.day-grid {
    display: grid;
    grid-template-columns: 80px 1fr;
    gap: 1px;
    background: var(--color-border);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    overflow: hidden;
    flex: 1;
    overflow-y: auto;
}

.day-time-column {
    background: var(--color-bg-secondary);
}

.day-content-column {
    background: var(--color-bg-primary);
    position: relative;
}

.day-event {
    position: absolute;
    left: var(--space-sm);
    right: var(--space-sm);
    padding: var(--space-md);
    border-radius: var(--radius-md);
    cursor: pointer;
    border-left: 4px solid;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.day-event:hover {
    transform: translateX(4px);
    box-shadow: var(--shadow-lg);
}

.day-event.personal { background: rgba(99, 102, 241, 0.08); border-left-color: var(--color-calendar-personal); }
.day-event.work { background: rgba(16, 185, 129, 0.08); border-left-color: var(--color-calendar-work); }
.day-event.family { background: rgba(245, 158, 11, 0.08); border-left-color: var(--color-calendar-family); }
.day-event.birthdays { background: rgba(236, 72, 153, 0.08); border-left-color: var(--color-calendar-birthdays); }

.day-event-time {
    font-size: 0.75rem;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-xs);
}

.day-event-title {
    font-weight: 600;
    color: var(--color-text-primary);
    margin-bottom: var(--space-xs);
}

.day-event-location {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    display: flex;
    align-items: center;
    gap: var(--space-xs);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    padding: var(--space-sm) var(--space-md);
    border: none;
    border-radius: var(--radius-md);
    font-family: var(--font-body);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn-primary {
    background: var(--color-accent);
    color: white;
}

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

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

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

.btn-icon {
    width: 40px;
    height: 40px;
    padding: 0;
    justify-content: center;
    background: transparent;
    color: var(--color-text-secondary);
    border-radius: 50%;
}

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

.btn .icon {
    width: 18px;
    height: 18px;
}

/* Modal */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(27, 10, 60, 0.5);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: 100;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--color-bg-elevated);
    border-radius: var(--radius-xl);
    width: 100%;
    max-width: 480px;
    max-height: 90vh;
    overflow: hidden;
    box-shadow: var(--shadow-xl);
    transform: scale(0.95);
    transition: transform var(--transition-base);
}

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

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

.modal-title {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 600;
}

.modal-close {
    width: 32px;
    height: 32px;
    border: none;
    background: transparent;
    color: var(--color-text-tertiary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.modal-close:hover {
    background: var(--color-bg-secondary);
    color: var(--color-text-primary);
}

.modal-close svg {
    width: 20px;
    height: 20px;
}

.modal-body {
    padding: var(--space-xl);
    overflow-y: auto;
    max-height: calc(90vh - 80px);
}

/* Form */
.form-group {
    margin-bottom: var(--space-lg);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-md);
}

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-sm);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: var(--space-sm) var(--space-md);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    background: var(--color-bg-secondary);
    color: var(--color-text-primary);
    font-family: var(--font-body);
    font-size: 0.875rem;
    transition: all var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--color-accent);
    background: var(--color-bg-primary);
}

.form-textarea {
    resize: vertical;
    min-height: 80px;
}

.form-actions {
    display: flex;
    justify-content: flex-end;
    gap: var(--space-md);
    margin-top: var(--space-xl);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--color-border);
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

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

.calendar-day {
    animation: fadeIn 0.3s ease;
}

.day-event,
.week-event {
    animation: slideUp 0.3s ease;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--color-border-hover);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-text-tertiary);
}

/* Responsive */
@media (max-width: 1024px) {
    .sidebar {
        width: 240px;
    }
    
    .current-date {
        font-size: 1.5rem;
    }
}

@media (max-width: 768px) {
    .app-container {
        flex-direction: column;
    }
    
    .sidebar {
        width: 100%;
        height: auto;
        max-height: 200px;
        border-right: none;
        border-bottom: 1px solid var(--color-border);
    }
    
    .main-header {
        flex-direction: column;
        gap: var(--space-md);
        align-items: flex-start;
    }
    
    .header-left {
        width: 100%;
        justify-content: space-between;
    }
    
    .header-right {
        width: 100%;
    }
    
    .search-box input {
        width: 100%;
    }
    
    .calendar-grid {
        grid-template-rows: repeat(6, minmax(80px, auto));
    }
    
    .calendar-day {
        min-height: 80px;
        padding: var(--space-xs);
    }
    
    .day-number {
        width: 24px;
        height: 24px;
        font-size: 0.75rem;
    }
}