:root {
    --bg-gradient-1: #0f172a;
    --bg-gradient-2: #1e1b4b;
    --bg-gradient-3: #312e81;
    
    --primary: #818cf8;
    --primary-hover: #a5b4fc;
    --primary-glow: rgba(129, 140, 248, 0.4);
    
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.3);
    
    --danger: #f43f5e;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text-main);
    min-height: 100vh;
    overflow-x: hidden;
    background-color: var(--bg-gradient-1);
}

.animated-bg {
    position: fixed;
    top: 0; left: 0; width: 100vw; height: 100vh;
    background: linear-gradient(125deg, var(--bg-gradient-1), var(--bg-gradient-2), var(--bg-gradient-3));
    background-size: 400% 400%;
    animation: gradientBG 15s ease infinite;
    z-index: -1;
}

@keyframes gradientBG {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.container {
    max-width: 1300px;
    margin: 0 auto;
    padding: 2rem;
}

.two-column-layout {
    display: flex;
    gap: 2rem;
    align-items: flex-start;
}

.left-column {
    flex: 0 0 520px;
    display: flex;
    flex-direction: column;
}

.right-column {
    flex: 1;
    min-width: 0;
}

@media (max-width: 1000px) {
    .two-column-layout {
        flex-direction: column;
    }
    .left-column {
        flex: 1;
        width: 100%;
        max-width: none;
    }
}

header {
    text-align: center;
    margin-bottom: 3rem;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    margin-bottom: 0.5rem;
}

.logo-icon {
    width: 32px;
    height: 32px;
    background: linear-gradient(135deg, var(--primary), #e879f9);
    border-radius: 8px;
    box-shadow: 0 0 20px var(--primary-glow);
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    background: linear-gradient(to right, #fff, #a5b4fc);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-muted);
    font-size: 1.1rem;
}

.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--glass-shadow);
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.glass-card:hover {
    border-color: rgba(255, 255, 255, 0.15);
}

.glass-card h2 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

#participants-container {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    align-items: flex-start;
}

.participant-card {
    flex: 1 1 calc(50% - 0.5rem);
    min-width: 220px;
    margin-bottom: 0;
    transition: all 0.3s ease;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.input-group label {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 500;
}

.glass-input {
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--glass-border);
    border-radius: 8px;
    padding: 0.75rem 1rem;
    color: var(--text-main);
    font-family: inherit;
    font-size: 1rem;
    transition: all 0.2s;
    width: 100%;
    outline: none;
}

.glass-input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px var(--primary-glow);
}

select.glass-input {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
    background-size: 1em;
}

select.glass-input option {
    background: var(--bg-gradient-2);
    color: var(--text-main);
}

.participant-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.participant-avatar {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    object-fit: cover;
    background: rgba(255,255,255,0.1);
    border: 2px solid var(--primary);
    box-shadow: 0 0 10px var(--primary-glow);
}

.name-input {
    font-size: 1.1rem;
    font-weight: 600;
    border: none;
    border-bottom: 1px solid var(--glass-border);
    border-radius: 0;
    padding: 0.5rem 0;
    background: transparent;
}

.name-input:focus {
    box-shadow: none;
    border-bottom-color: var(--primary);
}

.participant-details {
    display: none;
    margin-top: 1rem;
    border-top: 1px dashed rgba(255, 255, 255, 0.1);
    padding-top: 1rem;
}

.participant-card.expanded .participant-details {
    display: block;
}

.toggle-details-btn {
    transition: transform 0.3s ease;
    background: transparent;
    color: var(--text-muted);
}
.toggle-details-btn:hover {
    color: var(--text-main);
}
.participant-card.expanded .toggle-details-btn {
    transform: rotate(180deg);
}

.participant-details {
    display: none;
    margin-top: 1rem;
    border-top: 1px dashed rgba(255, 255, 255, 0.1);
    padding-top: 1rem;
}

.participant-card.expanded .participant-details {
    display: block;
}

.toggle-details-btn {
    transition: transform 0.3s ease;
    background: transparent;
    color: var(--text-muted);
}
.toggle-details-btn:hover {
    color: var(--text-main);
}
.participant-card.expanded .toggle-details-btn {
    transform: rotate(180deg);
}

.icon-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 1.5rem;
    cursor: pointer;
    transition: color 0.2s, transform 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: 50%;
}

.icon-btn:hover {
    color: var(--danger);
    background: rgba(244, 63, 94, 0.1);
    transform: scale(1.1);
}

.availability-list h4 {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.time-slot {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
    animation: slideIn 0.3s ease-out forwards;
}

@keyframes slideIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

.time-slot span {
    color: var(--text-muted);
    font-size: 0.875rem;
}

.glass-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    color: var(--text-main);
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-family: inherit;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.glass-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-2px);
}

.glass-btn:active {
    transform: translateY(0);
}

.glass-btn.primary {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
}

.glass-btn.primary:hover {
    background: var(--primary-hover);
    box-shadow: 0 0 20px var(--primary-glow);
}

.glass-btn.glowing {
    box-shadow: 0 0 15px var(--primary-glow);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% { box-shadow: 0 0 15px var(--primary-glow); }
    50% { box-shadow: 0 0 25px var(--primary-glow); }
    100% { box-shadow: 0 0 15px var(--primary-glow); }
}

.glass-btn.text-only {
    padding: 0.5rem;
    border: none;
    background: transparent;
    color: var(--primary);
    font-size: 0.875rem;
}

.glass-btn.text-only:hover {
    background: rgba(129, 140, 248, 0.1);
}

.actions-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 2rem;
    margin-bottom: 2rem;
    gap: 1rem;
}

@media (max-width: 600px) {
    .actions-bar {
        flex-direction: column;
    }
    .actions-bar button {
        width: 100%;
    }
}

.hidden {
    display: none !important;
}

#results-section {
    border-color: var(--primary);
    background: rgba(129, 140, 248, 0.05);
}

.result-item {
    padding: 1rem;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 8px;
    margin-bottom: 0.5rem;
    border: 1px solid rgba(129, 140, 248, 0.2);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.result-time {
    font-weight: 600;
    font-size: 1.1rem;
    color: var(--primary-hover);
}

.result-duration {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.no-overlap {
    text-align: center;
    color: var(--danger);
    padding: 2rem 0;
}

/* Timeline / Calendar View */
.timeline-container {
    width: 100%;
    margin-top: 1rem;
    overflow-x: auto;
    padding-bottom: 1rem;
}
.timeline-axis {
    display: flex;
    margin-left: 200px;
    border-bottom: 1px solid var(--glass-border);
    margin-bottom: 0.5rem;
}
.timeline-hour {
    flex: 1;
    text-align: left;
    font-size: 0.7rem;
    color: var(--text-muted);
    border-left: 1px solid rgba(255,255,255,0.05);
    padding-left: 4px;
    height: 20px;
}
.timeline-hour:first-child { border-left: none; }
.timeline-row {
    display: flex;
    align-items: center;
    margin-bottom: 0.5rem;
}
.timeline-label {
    width: 200px;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--primary-hover);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    padding-right: 10px;
}
.timeline-bars {
    flex: 1;
    position: relative;
    height: 30px;
    background: rgba(0,0,0,0.2);
    border-radius: 4px;
    border: 1px solid rgba(255,255,255,0.05);
}
.timeline-block {
    position: absolute;
    height: 100%;
    background: var(--primary);
    border-radius: 4px;
    opacity: 0.8;
    box-shadow: 0 0 10px var(--primary-glow);
    transition: all 0.3s;
}
.timeline-block:hover {
    opacity: 1;
    background: #e879f9;
}

/* Calendar Drag Modal */
.modal-overlay {
    position: fixed; top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0, 0, 0, 0.6); backdrop-filter: blur(8px);
    display: flex; justify-content: center; align-items: center;
    z-index: 1000;
}
.modal-content {
    width: 95%; max-width: 900px; max-height: 90vh;
    display: flex; flex-direction: column; overflow: hidden;
}
.modal-header {
    display: flex; justify-content: space-between; align-items: center;
    border-bottom: 1px solid var(--glass-border);
    padding-bottom: 1rem; margin-bottom: 1rem;
}
.calendar-controls {
    display: flex; justify-content: space-between; align-items: center;
    margin-bottom: 1rem; padding: 0 1rem;
}
.calendar-controls h4 { margin: 0; color: var(--text-main); font-size: 1.1rem; }
.modal-footer {
    display: flex; justify-content: flex-end; gap: 1rem;
    border-top: 1px solid var(--glass-border);
    padding-top: 1rem; margin-top: 1rem;
}

/* Interactive Calendar Grid */
#calendar-grid {
    flex: 1; overflow-y: auto; overflow-x: auto;
    background: rgba(0, 0, 0, 0.3); border-radius: 8px;
    border: 1px solid var(--glass-border);
    position: relative; user-select: none;
    min-height: 400px;
}
.cal-layout {
    display: flex; min-width: 700px; position: relative;
}
.cal-time-col {
    width: 50px; flex-shrink: 0; border-right: 1px solid var(--glass-border);
    background: rgba(0, 0, 0, 0.2); z-index: 2;
}
.cal-time-cell {
    height: 40px; font-size: 0.7rem; color: var(--text-muted);
    text-align: right; padding-right: 5px; position: relative;
}
.cal-time-cell span { position: absolute; top: 0; right: 8px; transform: translateY(-50%); }

.cal-days-container {
    display: flex; flex: 1; position: relative;
}
.cal-day-col {
    flex: 1; border-right: 1px solid rgba(255, 255, 255, 0.15);
    position: relative;
    display: flex; flex-direction: column;
}
.cal-day-col:last-child { border-right: none; }
.cal-day-header {
    text-align: center; padding: 0.5rem 0;
    border-bottom: 1px solid var(--glass-border);
    font-size: 0.85rem; font-weight: 600;
    position: sticky; top: 0; background: var(--bg-gradient-2); z-index: 3;
    border-right: 1px solid rgba(255, 255, 255, 0.15);
}
.cal-day-grid {
    position: relative; height: 960px; /* 24hr * 40px */
    flex: 1; cursor: crosshair;
}
.cal-hour-line {
    position: absolute; width: 100%; height: 1px;
    background: rgba(255, 255, 255, 0.15); pointer-events: none;
}
.cal-half-hour-line {
    position: absolute; width: 100%; height: 1px;
    border-top: 1px dashed rgba(255, 255, 255, 0.1); pointer-events: none;
}

/* Selection Blocks */
.cal-selection-block {
    position: absolute; left: 2px; right: 2px;
    background: rgba(129, 140, 248, 0.4);
    border: 1px solid var(--primary);
    border-radius: 4px; border-left: 3px solid #e879f9;
    box-shadow: 0 0 10px rgba(129, 140, 248, 0.2);
    display: flex; flex-direction: column; justify-content: flex-start;
    padding: 2px 4px; overflow: hidden; pointer-events: none;
}
.cal-selection-block.confirmed {
    background: rgba(129, 140, 248, 0.6); pointer-events: auto; cursor: pointer;
}
.cal-selection-block.confirmed:hover {
    background: rgba(129, 140, 248, 0.8);
}
.cal-selection-text {
    font-size: 0.7rem; color: #fff; line-height: 1.2;
    text-shadow: 0 1px 2px rgba(0,0,0,0.5); font-weight: 500;
}
.cal-resize-handle-top, .cal-resize-handle-bottom {
    position: absolute;
    left: 0; right: 0;
    height: 8px;
    cursor: ns-resize;
    z-index: 10;
}
.cal-resize-handle-top { top: -2px; }
.cal-resize-handle-bottom { bottom: -2px; }

.cal-remove-btn {
    position: absolute; top: 4px; right: 4px; background: rgba(0, 0, 0, 0.5);
    color: #fff; border: none; width: 16px; height: 16px; border-radius: 50%;
    font-size: 10px; line-height: 14px; text-align: center; cursor: pointer;
    display: none; padding: 0;
}
.cal-selection-block.confirmed:hover .cal-remove-btn { display: block; }
.cal-remove-btn:hover { background: #f43f5e; }