/* Drawing Board: modern, playful and school-friendly */
:root {
    --board-surface: #fffdf6;
    --board-panel: #ffffff;
    --board-ink: #243041;
    --board-muted: #607089;
    --board-line: #dce5f2;
    --board-accent: #ff7f11;
    --board-accent-soft: #ffd7a6;
    --board-blue: #2f3a8f;
    --board-blue-soft: #d9e0ff;
    --board-pink: #f05a7e;
    --board-green: #00a676;
    --board-shadow: 0 20px 45px rgba(19, 36, 68, 0.14);
    --title-font: 'Baloo 2', 'Trebuchet MS', sans-serif;
    --body-font: 'Nunito', 'Segoe UI', sans-serif;
}

html,
body {
    overflow-x: hidden;
}

body.board-mode-artistic .drawing-board-section {
    --mode-strong: var(--board-pink);
    --mode-soft: #ffe2ea;
}

body.board-mode-technical .drawing-board-section {
    --mode-strong: var(--board-blue);
    --mode-soft: #e3ebff;
}

.drawing-board-section {
    font-family: var(--body-font);
    color: var(--board-ink);
    background:
        radial-gradient(circle at 8% 14%, rgba(255, 127, 17, 0.16), transparent 36%),
        radial-gradient(circle at 88% 20%, rgba(240, 90, 126, 0.16), transparent 34%),
        var(--board-surface);
    border: 1px solid #f0f4ff;
    border-radius: 28px;
    margin: 2.4rem auto;
    max-width: 1120px;
    padding: 1.3rem;
    box-shadow: var(--board-shadow);
    position: relative;
    overflow: hidden;
}

.drawing-board-section::before {
    content: '';
    position: absolute;
    right: -80px;
    top: -80px;
    width: 260px;
    height: 260px;
    border-radius: 50%;
    background: linear-gradient(135deg, rgba(255, 127, 17, 0.2), rgba(255, 217, 166, 0));
    pointer-events: none;
}

.section-title {
    font-family: var(--title-font);
    font-size: clamp(1.7rem, 2.4vw, 2.3rem);
    line-height: 1.1;
    letter-spacing: 0.4px;
    margin-bottom: 0.5rem;
    color: #15223b;
}

.board-subtitle {
    margin: 0 0 1rem;
    color: var(--board-muted);
    font-size: 1rem;
}

.board-top-panel {
    display: grid;
    grid-template-columns: 1.1fr 1fr;
    gap: 1rem;
    margin-bottom: 1rem;
}

.mode-switch,
.mini-challenge {
    border-radius: 20px;
    background: var(--board-panel);
    border: 1px solid #e8edf6;
    padding: 0.85rem;
}

.mode-switch {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.8rem;
}

.mode-btn {
    border: none;
    background: #f6f8fd;
    border: 1px solid #dde5f2;
    border-radius: 14px;
    padding: 0.8rem 0.9rem;
    color: #1e2f4f;
    font-weight: 800;
    font-size: 0.95rem;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.mode-btn i {
    margin-right: 0.4rem;
}

.mode-btn:hover {
    transform: translateY(-1px);
}

.mode-btn.active {
    background: linear-gradient(120deg, var(--mode-soft), #ffffff);
    border-color: var(--mode-strong);
    box-shadow: 0 7px 16px rgba(47, 58, 143, 0.16);
}

.mini-challenge {
    display: flex;
    flex-direction: column;
    gap: 0.45rem;
}

.challenge-label {
    color: var(--board-blue);
    font-size: 0.88rem;
    font-weight: 800;
}

#challenge-text {
    margin: 0;
    color: #1c2c4a;
    font-weight: 700;
}

.mini-challenge-btn {
    align-self: flex-start;
    border: none;
    border-radius: 999px;
    background: linear-gradient(120deg, var(--board-accent), #ffba49);
    color: #fff;
    padding: 0.5rem 0.9rem;
    font-weight: 800;
    cursor: pointer;
}

.drawing-board-container {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 1rem;
    align-items: start;
}

.drawing-board-wrapper {
    position: relative;
    border-radius: 22px;
    overflow: hidden;
    background: #fff;
    border: 2px solid #ecf1f8;
    min-height: 520px;
    touch-action: none;
}

#drawing-canvas {
    width: 100%;
    height: 520px;
    display: block;
    background: #ffffff;
    cursor: crosshair;
    touch-action: none;
}

.board-grid-overlay {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(47, 58, 143, 0.08) 1px, transparent 1px),
        linear-gradient(90deg, rgba(47, 58, 143, 0.08) 1px, transparent 1px);
    background-size: 26px 26px;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease;
    z-index: 10;
}

.board-grid-overlay.visible {
    opacity: 1;
}

.angle-indicator {
    position: absolute;
    background: rgba(19, 36, 68, 0.9);
    color: #fff;
    border-radius: 8px;
    font-size: 0.86rem;
    padding: 0.35rem 0.55rem;
    pointer-events: none;
    z-index: 25;
    display: none;
    transform: translate(-50%, -50%);
}

.drawing-controls {
    border-radius: 22px;
    background: var(--board-panel);
    border: 1px solid #e7edf8;
    padding: 0.9rem;
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.control-group {
    border: 1px solid #edf1f8;
    border-radius: 14px;
    padding: 0.7rem;
    background: #fbfdff;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.control-title {
    font-size: 0.83rem;
    color: var(--board-muted);
    margin-right: 0.2rem;
    font-weight: 800;
}

.tool-btn {
    border: 1px solid #d6e1f2;
    background: #fff;
    border-radius: 11px;
    padding: 0.55rem 0.75rem;
    color: #1f2f4f;
    font-weight: 800;
    cursor: pointer;
    transition: all 0.16s ease;
}

.tool-btn:hover,
.tool-btn.active {
    background: #25385d;
    color: #fff;
    border-color: #25385d;
}

.swatch-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
}

.swatch-btn {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    border: 2px solid #fff;
    outline: 1px solid #ced9ea;
    background: var(--swatch);
    cursor: pointer;
    transition: transform 0.15s ease;
}

.swatch-btn[data-color="#ffffff"] {
    border-color: #d7e0ef;
}

.swatch-btn:hover,
.swatch-btn.active {
    transform: scale(1.12);
    outline-color: #4d5f81;
}

#color-picker {
    width: 44px;
    height: 44px;
    border: none;
    background: transparent;
    cursor: pointer;
}

#line-width {
    flex: 1;
    min-width: 130px;
    accent-color: var(--board-accent);
}

.line-width-value,
.forced-angle-display {
    min-width: 54px;
    text-align: center;
    background: #edf2ff;
    border-radius: 8px;
    font-weight: 800;
    color: var(--board-blue);
    padding: 0.3rem 0.35rem;
}

.selected-color-value {
    min-width: 86px;
    text-align: center;
    background: #eef4ff;
    border-radius: 8px;
    font-weight: 800;
    color: #243c66;
    padding: 0.3rem 0.45rem;
    letter-spacing: 0.2px;
}

.size-chip {
    border: 1px solid #d4deed;
    border-radius: 999px;
    background: #fff;
    color: #1f2f4f;
    padding: 0.42rem 0.72rem;
    font-weight: 800;
    cursor: pointer;
}

.size-chip.active,
.size-chip:hover {
    background: var(--board-blue-soft);
    border-color: var(--board-blue);
}

.drawing-board-btn {
    border: none;
    border-radius: 10px;
    font-weight: 800;
    padding: 0.6rem 0.85rem;
    cursor: pointer;
    color: #fff;
    background: linear-gradient(120deg, #3d5a80, #2f3a8f);
}

.drawing-board-btn.clear {
    background: linear-gradient(120deg, #d7263d, #ff4d6d);
}

.inline-check {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    font-size: 0.85rem;
    color: #32435f;
    font-weight: 700;
}

#angle-input {
    width: 78px;
    border: 1px solid #cfdbeb;
    border-radius: 8px;
    padding: 0.35rem;
}

@media (max-width: 1080px) {
    .drawing-board-container {
        grid-template-columns: 1fr;
    }

    .drawing-controls {
        width: 100%;
    }
}

@media (max-width: 768px) {
    .drawing-board-section {
        border-radius: 20px;
        margin: 1.4rem auto;
        padding: 0.95rem;
    }

    .board-top-panel {
        grid-template-columns: 1fr;
    }

    .mode-switch {
        grid-template-columns: 1fr;
    }

    #drawing-canvas,
    .drawing-board-wrapper {
        min-height: 420px;
        height: 420px;
    }

    .drawing-controls {
        gap: 0.65rem;
        padding: 0.75rem;
    }

    .control-group {
        align-items: stretch;
    }

    .tools-group {
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 0.45rem;
    }

    .tool-btn {
        width: 100%;
        white-space: nowrap;
        text-align: center;
    }
}

@media (max-width: 420px) {
    .section-title {
        font-size: 1.45rem;
    }

    .drawing-controls {
        gap: 0.55rem;
        padding: 0.65rem;
    }

    .control-group {
        padding: 0.6rem;
    }

    .tools-group {
        grid-template-columns: 1fr;
    }

    #drawing-canvas,
    .drawing-board-wrapper {
        min-height: 360px;
        height: 360px;
    }

    .drawing-board-btn {
        width: 100%;
        justify-content: center;
    }

    .action-group {
        display: grid;
        grid-template-columns: 1fr;
    }
}