*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    outline: none;
    -webkit-tap-highlight-color: transparent;
}

:root {
    --clr-bg: #f4f6f8;
    --clr-dots: #d0d0d0;
    --clr-ink: #111111;
    --clr-paper: #ffffff;
    --clr-yellow: #ffde00;
    --clr-purple: #7d5fff;
    --clr-green: #33ff99;
    --clr-orange: #ff8c00;
    --clr-red: #ff3366;
    --border-width: 4px;
    --shadow-offset: clamp(4px, 1vw, 8px);
    --transition: 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    --fs-header: clamp(1.2rem, 4vw, 2.2rem);
    --fs-body: clamp(0.8rem, 2vw, 1rem);
    --toolbar-height: auto;
    --anim-speed: 0.15s;
}

body {
    background-color: var(--clr-bg);
    background-image: radial-gradient(var(--clr-dots) 10%, transparent 11%), radial-gradient(var(--clr-dots) 10%, transparent 11%);
    background-size: 20px 20px;
    background-position: 0 0, 10px 10px;
    font-family: var(--font-body);
    height: 100vh;
    height: 100dvh;
    overflow: hidden;
    color: var(--clr-ink);
}

#page-loader {
    position: fixed;
    inset: 0;
    background: var(--clr-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10000;
}

#page-loader.hidden {
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.5s ease, visibility 0.5s;
}

.loader-spinner {
    width: 60px;
    height: 60px;
    border: 6px solid var(--clr-ink);
    border-top-color: var(--clr-purple);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    box-shadow: 4px 4px 0 var(--clr-ink);
}

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

.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    height: 100dvh;
    padding: clamp(2px, 1vw, 10px);
    gap: 8px;
    overflow: hidden;
}

.top-bar, .tool-bar {
    background: var(--clr-paper);
    border: var(--border-width) solid var(--clr-ink);
    box-shadow: var(--shadow-offset) var(--shadow-offset) 0 var(--clr-ink);
    padding: 8px 12px;
    display: flex;
    align-items: center;
    z-index: 100;
    flex-shrink: 0;
    gap: 15px;
}

.top-bar {
    justify-content: space-between;
}

.bar-left, .bar-right {
    display: flex;
    align-items: center;
    gap: 10px;
}

.tool-bar {
    justify-content: center;
    overflow-x: auto;
    overflow-y: hidden;
    -webkit-overflow-scrolling: touch;
    white-space: nowrap;
    padding: 8px 15px;
    gap: 20px;
    scrollbar-width: thin;
}

@media (max-width: 800px) {
    .tool-bar { justify-content: flex-start; }
}

.tool-bar::-webkit-scrollbar {
    height: 4px;
    display: block;
}
.tool-bar::-webkit-scrollbar-track { background: transparent; }
.tool-bar::-webkit-scrollbar-thumb { 
    background: var(--clr-dots); 
    border-radius: 10px;
}

.home-btn {
    background: var(--clr-yellow);
    color: var(--clr-ink);
    border: 3px solid var(--clr-ink);
    padding: 5px 12px;
    font-family: var(--font-header);
    text-decoration: none;
    font-size: 1.1rem;
    box-shadow: 2px 2px 0 var(--clr-ink);
    transition: var(--transition);
}

.room-info {
    font-weight: 800;
    font-size: 0.8rem;
    background: #eeeeee;
    padding: 4px 8px;
    border: 2px solid var(--clr-ink);
    display: flex;
    align-items: center;
    gap: 5px;
}

#room-id-display {
    max-width: 80px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.view-controls {
    display: flex;
    gap: 5px;
}

.view-controls button {
    width: 35px;
    padding: 0;
    height: 35px;
    font-size: 1.2rem;
    background: #e0e0e0;
}

#reset-view {
    font-size: 0.7rem;
    font-family: var(--font-body);
    font-weight: 800;
}

.export-group {
    margin-left: auto;
}

.tool-bar .control-group {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-shrink: 0;
}

.tool-bar button {
    min-width: 44px;
    height: 40px;
    padding: 0 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: 800;
}

#undo-btn, #redo-btn { font-size: 1.3rem; min-width: 40px; }

#color-picker {
    width: 35px;
    height: 35px;
    border: 3px solid var(--clr-ink);
    background: none;
    cursor: pointer;
    padding: 0;
}

.brush-settings {
    display: flex;
    align-items: center;
    gap: 0;
    border-left: 2px solid var(--clr-ink);
    height: 40px;
}

.size-slider-wrapper {
    display: flex;
    align-items: center;
    width: 0;
    overflow: hidden;
    transition: width 0.4s cubic-bezier(0.4, 0, 0.2, 1), padding 0.3s;
    background: var(--clr-paper);
    gap: 12px;
}

.brush-settings.active .size-slider-wrapper {
    width: 200px;
    padding: 0 15px;
    border-right: 2px solid var(--clr-ink);
}

.size-preview-wrap {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

#size-preview {
    background: var(--clr-ink);
    border-radius: 50%;
    width: 4px;
    height: 4px;
}

#size-slider {
    flex: 1;
    cursor: pointer;
    accent-color: var(--clr-ink);
}

button {
    font-family: var(--font-header);
    background: white;
    border: 3px solid var(--clr-ink);
    padding: 8px 18px;
    font-size: 0.95rem;
    cursor: pointer;
    box-shadow: 4px 4px 0 var(--clr-ink);
    transition: all var(--anim-speed) cubic-bezier(0.4, 0, 0.2, 1);
    white-space: nowrap;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    user-select: none;
}

button:hover { 
    transform: translate(-2px, -2px); 
    box-shadow: 6px 6px 0 var(--clr-ink); 
}

button:active { 
    transform: translate(2px, 2px); 
    box-shadow: 1px 1px 0 var(--clr-ink); 
}
#undo-btn, #redo-btn {
    font-size: 1.4rem;
    padding: 2px 10px;
    font-weight: 900;
}
button.active { 
    background: var(--clr-purple); 
    color: white; 
    border-color: var(--clr-ink); 
}
button.danger { background: var(--clr-red); color: white; }
button.mini-btn { padding: 2px 6px; font-size: 0.6rem; margin-left: 0; box-shadow: 1px 1px 0 var(--clr-ink); }

#peer-count {
    background: var(--clr-purple);
    color: white;
    width: 25px;
    height: 25px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    font-weight: 900;
    border: 2px solid var(--clr-ink);
    box-shadow: 1px 1px 0 var(--clr-ink);
    font-size: 0.7rem;
}

#chat-btn {
    position: relative;
    padding: 4px 10px;
    font-size: 0.75rem;
}

.notification-dot {
    position: absolute;
    top: -2px;
    right: -2px;
    width: 10px;
    height: 10px;
    background: var(--clr-red);
    border: 1.5px solid var(--clr-ink);
    border-radius: 50%;
    animation: pulse-red 1.5s infinite;
}

@keyframes pulse-red {
    0% { transform: scale(0.9); box-shadow: 0 0 0 0 rgba(255, 51, 102, 0.7); }
    70% { transform: scale(1.1); box-shadow: 0 0 0 5px rgba(255, 51, 102, 0); }
    100% { transform: scale(0.9); box-shadow: 0 0 0 0 rgba(255, 51, 102, 0); }
}

.status-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #ccc;
    border: 2px solid var(--clr-ink);
}
.status-dot.online { background: var(--clr-green); }
.status-dot.offline { background: var(--clr-red); }

.canvas-wrapper {
    flex: 1;
    position: relative;
    background: white;
    border: var(--border-width) solid var(--clr-ink);
    box-shadow: var(--shadow-offset) var(--shadow-offset) 0 var(--clr-ink);
    overflow: hidden;
    cursor: crosshair;
    touch-action: none;
    min-height: 0;
}

#whiteboard {
    display: block;
    width: 100%;
    height: 100%;
}

#cursors-container {
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.remote-cursor {
    position: absolute;
    width: 14px;
    height: 14px;
    background: white;
    border: 3px solid var(--clr-ink);
    border-radius: 50% 50% 50% 0;
    box-shadow: 3px 3px 0 rgba(17, 17, 17, 0.2);
    transform: translate(-50%, -50%);
    pointer-events: none;
    z-index: 1000;
    will-change: left, top;
}

.cursor-label {
    position: absolute;
    top: -36px;
    left: 10px;
    background: inherit;
    color: white;
    padding: 4px 9px;
    font-size: 11px;
    font-weight: 900;
    white-space: nowrap;
    border: 2px solid var(--clr-ink);
    box-shadow: 3px 3px 0 var(--clr-ink);
    border-radius: 4px;
    text-shadow: 1px 1px 0 rgba(0,0,0,0.2);
    pointer-events: none;
}

.cursor-label::after {
    content: '';
    position: absolute;
    bottom: -6px;
    left: 4px;
    width: 0;
    height: 0;
    border-left: 6px solid transparent;
    border-right: 6px solid transparent;
    border-top: 6px solid var(--clr-ink);
}

.chat-modal {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: min(350px, 90vw);
    background: white;
    border: var(--border-width) solid var(--clr-ink);
    box-shadow: 10px 10px 0 var(--clr-ink);
    display: flex;
    flex-direction: column;
    z-index: 1500;
}

.chat-modal.hidden {
    display: none;
}

.chat-header {
    background: var(--clr-purple);
    color: white;
    padding: 12px 15px;
    font-family: var(--font-header);
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: var(--border-width) solid var(--clr-ink);
    font-size: 1.2rem;
    letter-spacing: 1px;
}

#close-chat {
    background: white;
    color: var(--clr-ink);
    border: 2px solid var(--clr-ink);
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: Arial, sans-serif;
    font-weight: bold;
    font-size: 1.4rem;
    cursor: pointer;
    box-shadow: 3px 3px 0 var(--clr-ink);
    padding: 0;
    line-height: 1;
}

#close-chat:hover {
    background: var(--clr-red);
    color: white;
    transform: translate(-1px, -1px);
    box-shadow: 4px 4px 0 var(--clr-ink);
}

.chat-body { 
    height: 350px; 
    max-height: 60vh;
    display: flex; 
    flex-direction: column; 
    background: var(--clr-bg);
}

#chat-messages { 
    flex: 1; 
    overflow-y: auto; 
    padding: 15px; 
    display: flex; 
    flex-direction: column; 
    gap: 12px; 
    scrollbar-width: thin;
}

.msg {
    max-width: 85%;
    padding: 10px 14px;
    border: 2px solid var(--clr-ink);
    font-weight: 700;
    line-height: 1.4;
    position: relative;
    box-shadow: 4px 4px 0 var(--clr-ink);
    font-size: 0.9rem;
}

.msg-author {
    font-family: var(--font-header);
    font-size: 0.75rem;
    letter-spacing: 0.5px;
    margin-bottom: 4px;
    text-transform: uppercase;
    display: block;
}

.msg.sent {
    align-self: flex-end;
    background: var(--clr-yellow);
    border-bottom-right-radius: 0;
}

.msg.sent .msg-author {
    color: var(--clr-purple);
    text-align: right;
}

.msg.received {
    align-self: flex-start;
    background: white;
    border-bottom-left-radius: 0;
}

.msg.received .msg-author {
    color: #555;
}

#chat-form {
    padding: 12px;
    border-top: 3px solid var(--clr-ink);
    display: flex;
    gap: 8px;
    background: white;
}

#chat-form input {
    flex: 1;
    padding: 10px 15px;
    border: 3px solid var(--clr-ink);
    font-family: var(--font-body);
    font-weight: 700;
    font-size: 1rem;
    background: #fdfdfd;
}

#chat-form button {
    background: var(--clr-green);
    color: var(--clr-ink);
    border: 3px solid var(--clr-ink);
    padding: 0 15px;
    font-family: var(--font-header);
    font-size: 1.2rem;
    box-shadow: 4px 4px 0 var(--clr-ink);
    cursor: pointer;
}

#chat-form button:active {
    transform: translate(2px, 2px);
    box-shadow: 2px 2px 0 var(--clr-ink);
}

.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.85);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    padding: 20px;
}

.modal {
    background: var(--clr-bg);
    border: var(--border-width) solid var(--clr-ink);
    box-shadow: 10px 10px 0 var(--clr-ink);
    padding: clamp(20px, 5vw, 40px);
    max-width: 400px;
    width: 100%;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.modal h2 { font-family: var(--font-header); font-size: var(--fs-header); }
.modal input { padding: 12px; border: 3px solid var(--clr-ink); font-size: 1.1rem; text-align: center; }

#join-btn {
    background: var(--clr-green);
    padding: 15px;
    font-size: 1.3rem;
    box-shadow: 5px 5px 0 var(--clr-ink);
}

.members-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
    max-height: 250px;
    overflow-y: auto;
    padding-right: 5px;
    text-align: left;
}

.connection-pill {
    display: flex;
    align-items: center;
    gap: 8px;
    background: #f0f0f0;
    padding: 6px 12px;
    border-radius: 20px;
    border: 2px solid var(--clr-ink);
    font-size: 0.85rem;
    font-weight: 800;
    cursor: pointer;
    transition: transform 0.1s;
}

.connection-pill:active { transform: scale(0.95); }

.status-dot {
    width: 10px;
    height: 10px;
    background: #ccc;
    border-radius: 50%;
    border: 1.5px solid var(--clr-ink);
}

.status-dot.online {
    background: var(--clr-green);
}

.member-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px;
    background: var(--clr-paper);
    border: 2px solid var(--clr-ink);
    font-weight: 700;
}

.member-color {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    border: 1.5px solid var(--clr-ink);
}

.member-you {
    margin-left: auto;
    font-size: 0.7rem;
    color: var(--clr-purple);
    border: 1px solid var(--clr-purple);
    padding: 1px 4px;
    border-radius: 4px;
}

#close-members {
    background: var(--clr-orange);
    padding: 12px;
    margin-top: 10px;
}

.hidden { display: none !important; }

@media (max-width: 600px) {
    .app-container {
        padding-bottom: constant(safe-area-inset-bottom);
        padding-bottom: env(safe-area-inset-bottom);
    }

    .tool-bar {
        order: 3;
        width: 100%;
        justify-content: flex-start;
        padding: 8px 10px;
        gap: 10px;
        box-shadow: 0 -4px 0 var(--clr-ink); 
        padding-bottom: constant(safe-area-inset-bottom);
        padding-bottom: env(safe-area-inset-bottom);
    }
    
    .bar-right {
        position: static;
        pointer-events: auto;
    }

    .tool-bar .control-group {
        gap: 6px;
    }

    button {
        padding: 6px 12px;
        font-size: 0.75rem;
    }
    
    .view-controls { display: none; }
}