:root {
    /* Color Palette - Clean & Professional */
    --color-bg: #f3f4f6;
    --color-surface: #ffffff;
    --color-surface-alt: #f9fafb;

    --color-primary: #2563eb;
    --color-primary-hover: #1d4ed8;
    --color-primary-light: #eff6ff;

    --color-text: #111827;
    --color-text-secondary: #4b5563;
    --color-text-muted: #9ca3af;

    --color-border: #e5e7eb;
    --color-danger: #ef4444;
    --color-success: #10b981;

    /* Spacing & Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);

    /* Transitions */
    --transition: 0.15s ease-in-out;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    -webkit-font-smoothing: antialiased;
}

/* Header */
.header {
    height: 64px;
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    position: sticky;
    top: 0;
    z-index: 50;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    color: var(--color-text);
    font-weight: 800;
    font-size: 1.25rem;
    letter-spacing: -0.025em;
}

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
}

.auth-buttons,
.user-menu {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.user-email {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    font-weight: 500;
}

/* Main Layout */
.container {
    flex: 1;
    max-width: 1400px;
    width: 100%;
    margin: 0 auto;
    padding: 2rem;
    display: flex;
    flex-direction: column;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.625rem 1.25rem;
    border-radius: var(--radius-md);
    font-weight: 500;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all var(--transition);
    border: 1px solid transparent;
    gap: 0.5rem;
    font-family: 'Inter', sans-serif;
}

.btn-primary {
    background-color: var(--color-primary);
    color: white;
    box-shadow: 0 2px 4px rgba(37, 99, 235, 0.2);
}

.btn-primary:hover {
    background-color: var(--color-primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 6px rgba(37, 99, 235, 0.3);
}

.btn-secondary {
    background-color: white;
    border-color: var(--color-border);
    color: var(--color-text);
}

.btn-secondary:hover {
    background-color: var(--color-surface-alt);
    border-color: var(--color-text-muted);
}

.btn-text {
    background: transparent;
    color: var(--color-text-secondary);
    padding: 0.5rem 1rem;
}

.btn-text:hover {
    color: var(--color-text);
    background-color: var(--color-surface-alt);
}

/* Home View */
.home-layout {
    display: grid;
    grid-template-columns: 1fr 1.5fr 1fr;
    gap: 4rem;
    align-items: start;
    padding-top: 2rem;
}

.column-title {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-text-muted);
    font-weight: 700;
    margin-bottom: 1.5rem;
}

.alternatives-list,
.side-column {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.alternative-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--color-text-muted);
    font-size: 0.9375rem;
    font-weight: bold;
    color: black;
    text-decoration: line-through;
    opacity: 0.7;
}

.center-card {
    text-align: center;
    padding: 4rem 2rem;
    background: white;
    border-radius: 2rem;
    border: 1px solid var(--color-border);
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.05);
}

.center-card h2 {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 1rem;
    color: var(--color-text);
    background: linear-gradient(135deg, var(--color-text) 0%, var(--color-text-secondary) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.description {
    color: var(--color-text-secondary);
    font-size: 1.25rem;
    margin-bottom: 3rem;
    max-width: 400px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.6;
}

.button-group {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    max-width: 300px;
    margin: 0 auto;
}

.feature-item {
    display: flex;
    gap: 1rem;
    align-items: flex-start;
}

.feature-icon {
    width: 3rem;
    height: 3rem;
    border-radius: 1rem;
    background: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    flex-shrink: 0;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
}

.feature-text h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.feature-text p {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    line-height: 1.5;
}

/* Forms & Inputs */
.input-group {
    margin-bottom: 1rem;
}

.input-code {
    width: 100%;
    padding: 1rem 1.25rem;
    border: 2px solid var(--color-border);
    border-radius: 1rem;
    font-size: 1.125rem;
    font-family: 'Inter', sans-serif;
    transition: all var(--transition);
    background: var(--color-surface-alt);
}

.input-code:focus {
    outline: none;
    background: white;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 4px var(--color-primary-light);
}

/* Room View */
.room-code-display {
    margin: 2.5rem 0;
}

.room-code {
    font-size: 4rem;
    font-weight: 800;
    font-family: monospace;
    letter-spacing: 0.5rem;
    color: var(--color-primary);
    text-shadow: 0 4px 8px rgba(37, 99, 235, 0.2);
}

/* Chat Interface */
.chat-layout-wrapper {
    display: flex;
    gap: 1.5rem;
    height: calc(100vh - 120px);
    max-width: 1400px;
    margin: 0 auto;
}

.chat-container {
    flex: 1;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.5);
    border-radius: 24px;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.1);
    height: 100%;
}

.pinned-sidebar {
    width: 300px;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.5);
    border-radius: 24px;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.1);
    height: 100%;
}

.pinned-header {
    padding: 1.5rem;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    font-weight: 700;
    color: var(--color-text);
}

.pinned-list {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.pinned-item {
    background: white;
    padding: 0.75rem;
    border-radius: 0.75rem;
    font-size: 0.85rem;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.02);
    border: 1px solid rgba(0, 0, 0, 0.05);
    position: relative;
    cursor: pointer;
    transition: all 0.2s;
    word-wrap: break-word;
    overflow-wrap: break-word;
}

.pinned-item:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

.empty-pinned {
    text-align: center;
    color: var(--color-text-muted);
    margin-top: 2rem;
    font-size: 0.9rem;
}

.chat-header {
    padding: 1rem 2rem;
    background: rgba(255, 255, 255, 0.8);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    display: flex;
    align-items: center;
    justify-content: space-between;
    z-index: 10;
}

.chat-controls {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.search-box {
    position: relative;
}

.search-input {
    padding: 0.5rem 1rem;
    border-radius: 99px;
    border: 1px solid var(--color-border);
    font-family: 'Inter', sans-serif;
    font-size: 0.9rem;
    width: 200px;
    transition: all 0.2s;
}

.search-input:focus {
    outline: none;
    border-color: var(--color-primary);
    width: 250px;
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

.chat-info h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text);
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.chat-info h3 span {
    background: var(--color-primary-light);
    color: var(--color-primary);
    padding: 0.25rem 0.75rem;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 4px var(--color-primary-light);
}

#messages {
    flex: 1;
    padding: 0.5rem;
    overflow-y: auto;
    background-color: transparent;
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.message {
    padding-bottom: inherit;
    max-width: 60%;
    display: flex;
    flex-direction: initial;
    animation: fadeIn 0.3s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(5px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes highlight {

    0%,
    100% {
        background-color: transparent;
    }

    50% {
        background-color: rgba(251, 191, 36, 0.2);
    }
}

.message-sent,
.message-received {
    align-self: flex-start;
    align-items: flex-start;
}

.message-content {
    padding: 0.25rem 0.5rem;
    border-radius: 0.75rem;
    position: relative;
    font-size: 0.9rem;
    line-height: 1;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.02);
    word-wrap: break-word;
    overflow-wrap: break-word;
    white-space: pre-line;
    text-align: left !important;
    direction: ltr !important;
}

.message-sent .message-content {
    background: var(--color-primary);
    color: white;
}

.message-received .message-content {
    background: white;
    color: var(--color-text);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

.message-time {
    font-size: 0.65rem;
    margin-top: 0.1rem;
    opacity: 0.7;
    display: block;
    text-align: right;
}

.message-actions {
    display: flex;
    gap: 0.25rem;
    margin-top: 0.1rem;
    opacity: 0;
    transition: opacity 0.2s;
}

.message:hover .message-actions {
    opacity: 1;
}

.btn-icon {
    background: white;
    border: 1px solid var(--color-border);
    border-radius: 50%;
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 0.7rem;
    transition: all 0.2s;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
}

.btn-icon:hover {
    transform: scale(1.1);
    border-color: var(--color-primary);
    z-index: 2;
}

.message.pinned .message-content {
    border: 2px solid #fbbf24;
}

.btn-unpin {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    background: rgba(0, 0, 0, 0.05);
    border: none;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1rem;
    line-height: 1;
    color: var(--color-text-secondary);
    transition: all 0.2s;
}

.btn-unpin:hover {
    background: var(--color-danger);
    color: white;
}

.message-input-container {
    padding: 0.75rem 1.5rem;
    background: rgba(255, 255, 255, 0.8);
    border-top: 1px solid rgba(0, 0, 0, 0.05);
    display: flex;
    gap: 1rem;
    align-items: center;
}

.message-input {
    flex: 1;
    padding: 0.75rem 1.25rem;
    border: 2px solid transparent;
    border-radius: 99px;
    font-family: 'Inter', sans-serif;
    font-size: 0.95rem;
    background: white;
    transition: all 0.2s;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    text-align: left;
    direction: ltr;
}

.message-input:focus {
    outline: none;
    background: white;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 4px var(--color-primary-light);
}

.btn-send {
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    background: var(--color-primary);
    color: white;
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: 0 4px 10px rgba(37, 99, 235, 0.3);
}

.btn-send:hover {
    background-color: var(--color-primary-hover);
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 8px 20px rgba(37, 99, 235, 0.4);
}

/* Plans */
.plans-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.plan-card {
    background: white;
    border: 1px solid var(--color-border);
    border-radius: 1.5rem;
    padding: 2.5rem;
    text-align: left;
    transition: all 0.3s;
}

.plan-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.1);
}

.plan-card.featured {
    border: 2px solid var(--color-primary);
    position: relative;
    overflow: hidden;
}

.plan-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: var(--color-primary-light);
    color: var(--color-primary);
    font-size: 0.75rem;
    font-weight: 700;
    padding: 0.25rem 0.75rem;
    border-radius: 99px;
}

.plan-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.plan-price {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--color-text);
}

.plan-price span {
    font-size: 1rem;
    color: var(--color-text-secondary);
    font-weight: 400;
}

.old-price {
    text-decoration: line-through;
    color: var(--color-text-muted);
    font-size: 1.25rem;
    margin-right: 0.5rem;
}

.plan-features {
    list-style: none;
    margin: 2rem 0;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.plan-features li {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1rem;
    color: var(--color-text-secondary);
}

/* Auth Card */
.auth-card {
    max-width: 420px;
    margin: 4rem auto;
    padding: 3rem 2.5rem;
    background: white;
    border-radius: 2rem;
    border: 1px solid var(--color-border);
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.08);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.auth-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 6px;
    background: linear-gradient(90deg, var(--color-primary), #60a5fa);
}

.auth-card h2 {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
    color: var(--color-text);
}

/* Footer */
.footer {
    padding: 3rem 2rem;
    text-align: center;
    border-top: 1px solid var(--color-border);
    margin-top: auto;
    background: white;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 1.5rem;
}

.footer-link {
    color: var(--color-text-muted);
    text-decoration: none;
    font-size: 0.875rem;
    transition: color 0.2s;
}

.footer-link:hover {
    color: var(--color-text);
}

/* Utilities */
.view {
    display: none;
    width: 100%;
    animation: fadeIn 0.3s ease-out;
}

.view.active {
    display: block;
}

.error-message {
    color: var(--color-danger);
    font-size: 0.875rem;
    margin-top: 0.5rem;
    padding: 0.5rem;
    background: #fef2f2;
    border-radius: var(--radius-md);
    text-align: center;
}

.auth-link {
    margin-top: 1.5rem;
    font-size: 0.875rem;
    color: var(--color-text-secondary);
}

.auth-link a {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 600;
}

.toast {
    font-family: 'Inter', sans-serif;
}

.toast.show {
    opacity: 1 !important;
    transform: translateX(-50%) translateY(0) !important;
}

/* Responsive */
@media (max-width: 1024px) {
    .home-layout {
        grid-template-columns: 1fr;
        max-width: 600px;
        margin: 0 auto;
        gap: 3rem;
    }

    .center-card {
        order: -1;
    }

    .chat-layout-wrapper {
        flex-direction: column;
        height: auto;
    }

    .pinned-sidebar {
        width: 100%;
        max-height: 300px;
    }
}

@media (max-width: 640px) {
    .header {
        padding: 0 1rem;
    }

    .container {
        padding: 1rem;
    }

    .center-card h2 {
        font-size: 2.5rem;
    }

    .chat-container {
        height: calc(100vh - 100px);
        border-radius: 16px;
    }

    .message {
        max-width: 85%;
    }
}

/* Guest Mode (Unlogged-in users) */
body:not(.logged-in) .pinned-sidebar {
    display: none !important;
}

body:not(.logged-in) .message-actions {
    display: none !important;
}

body:not(.logged-in) .search-box {
    display: none !important;
}

/* Logged-in users - hide home navigation */
body.logged-in .logo {
    pointer-events: none;
    opacity: 0.7;
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    .home-layout {
        grid-template-columns: 1fr;
        gap: 3rem;
        padding: 1rem;
        width: 100%;
        max-width: 100%;
    }

    .center-card {
        order: -1;
        padding: 3rem 1.5rem;
        margin-bottom: 2rem;
    }

    .center-card h2 {
        font-size: 2.5rem;
    }

    .side-column {
        align-items: center;
        text-align: center;
        background: white;
        padding: 2rem;
        border-radius: 1.5rem;
        border: 1px solid var(--color-border);
    }

    .column-title {
        font-size: 0.875rem;
        margin-bottom: 1.5rem;
    }

    .alternatives-list {
        width: 100%;
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
        gap: 1rem;
    }

    .alternative-item {
        justify-content: center;
        padding: 0.75rem;
        background: var(--color-surface-alt);
        border-radius: 0.75rem;
        width: 100%;
    }

    .feature-item {
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: 0.75rem;
    }

    .feature-icon {
        width: 3.5rem;
        height: 3.5rem;
        font-size: 1.75rem;
    }
}

/* Plan View Styles */
.center-card {
    max-width: 800px;
    margin: 0rem auto;
    padding: 3rem 2rem;
    background: white;
    border-radius: 2rem;
    border: 1px solid var(--color-border);
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.08);
    text-align: center;
}

.plans-container {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 3rem;
    flex-wrap: wrap;
}

.plan-card {
    flex: 1;
    min-width: 280px;
    padding: 2rem;
    border-radius: 1.5rem;
    border: 1px solid var(--color-border);
    background: var(--color-bg);
    position: relative;
    transition: all 0.3s ease;
}

.plan-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-primary);
}

.plan-card.featured {
    border: 2px solid var(--color-primary);
    background: white;
    transform: scale(1.05);
}

.plan-card.featured:hover {
    transform: scale(1.05) translateY(-5px);
}

.plan-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--color-primary);
    color: white;
    padding: 0.5rem 1.5rem;
    border-radius: 99px;
    font-weight: 700;
    font-size: 0.875rem;
    box-shadow: var(--shadow-md);
}

/* Mobile Header Adjustments */
@media (max-width: 640px) {
    .nav-link-extension {
        display: none !important;
    }

    .header {
        padding: 0 1rem;
    }

    .header-right {
        gap: 0.5rem !important;
    }

    .auth-buttons {
        gap: 0.5rem;
    }

    .auth-buttons .btn {
        padding: 0.5rem 0.75rem;
        font-size: 0.875rem;
    }
    
    .logo span {
        display: none; /* Hide logo text on small screens to save space */
    }
}