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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    min-height: 100vh;
    color: #e0e0e0;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    padding: 20px 0;
}

header h1 {
    font-size: 2.2em;
    background: linear-gradient(90deg, #00d4ff, #7c3aed, #f472b6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 10px;
}

.subtitle {
    color: #94a3b8;
    font-size: 1em;
}

/* Вкладки */
.tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 30px;
    justify-content: center;
}

.tab {
    padding: 12px 20px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    color: #94a3b8;
    cursor: pointer;
    transition: all 0.3s;
    font-size: 0.9em;
}

.tab:hover {
    background: rgba(255, 255, 255, 0.1);
    color: #fff;
}

.tab.active {
    background: linear-gradient(135deg, #7c3aed, #00d4ff);
    color: #fff;
    border-color: transparent;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.section-header {
    text-align: center;
    margin-bottom: 30px;
}

.section-header h2 {
    font-size: 1.8em;
    color: #00d4ff;
    margin-bottom: 10px;
}

.section-header p {
    color: #94a3b8;
}

/* Общие панели */
.input-panel, .solution-panel, .graph-panel {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 20px;
    padding: 25px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 25px;
}

/* Кнопка решения */
.solve-btn {
    padding: 12px 30px;
    font-size: 1.1em;
    font-weight: bold;
    background: linear-gradient(90deg, #00d4ff, #7c3aed);
    border: none;
    border-radius: 10px;
    color: #fff;
    cursor: pointer;
    transition: all 0.3s;
}

.solve-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(0, 212, 255, 0.4);
}

/* ==================== ФУНКЦИИ ==================== */
.function-selector {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
    margin-bottom: 25px;
}

.function-selector h3 {
    color: #f472b6;
    margin-bottom: 15px;
    text-align: center;
}

.function-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
}

.func-btn {
    padding: 15px 20px;
    background: rgba(0, 0, 0, 0.3);
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    color: #e0e0e0;
    cursor: pointer;
    transition: all 0.3s;
    text-align: center;
    min-width: 120px;
}

.func-btn:hover {
    border-color: #00d4ff;
    background: rgba(0, 212, 255, 0.1);
}

.func-btn.active {
    border-color: #00d4ff;
    background: rgba(0, 212, 255, 0.2);
    color: #00d4ff;
}

.func-btn small {
    display: block;
    color: #94a3b8;
    font-size: 0.8em;
    margin-top: 5px;
}

.function-explorer {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 25px;
    margin-bottom: 25px;
}

@media (max-width: 900px) {
    .function-explorer {
        grid-template-columns: 1fr;
    }
}

.controls-panel {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
}

#functionControls {
    margin-bottom: 20px;
}

#functionControls .control-item {
    margin-bottom: 15px;
}

#functionControls label {
    display: block;
    color: #94a3b8;
    margin-bottom: 5px;
    font-size: 0.9em;
}

#functionControls input[type="range"] {
    width: 100%;
    margin-bottom: 5px;
}

#functionControls .value-display {
    text-align: center;
    color: #00d4ff;
    font-weight: bold;
}

.function-info {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 10px;
    padding: 15px;
}

.function-info h4 {
    color: #fbbf24;
    margin-bottom: 10px;
}

.function-info p {
    color: #94a3b8;
    font-size: 0.9em;
    line-height: 1.6;
    margin-bottom: 8px;
}

.graph-panel canvas {
    display: block;
    margin: 0 auto;
    background: #0a0a0a;
    border-radius: 10px;
}

.graph-interactive {
    text-align: center;
    margin-top: 15px;
    color: #94a3b8;
}

.point-info {
    margin-top: 10px;
    padding: 10px;
    background: rgba(0, 212, 255, 0.1);
    border-radius: 8px;
    display: none;
}

.point-info.visible {
    display: block;
}

.function-properties {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
}

.properties-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.property-item {
    background: rgba(0, 0, 0, 0.3);
    padding: 15px;
    border-radius: 10px;
    border-left: 3px solid #7c3aed;
}

.property-item h5 {
    color: #7c3aed;
    margin-bottom: 5px;
}

.property-item p {
    color: #94a3b8;
    font-size: 0.9em;
}

/* ==================== СВЯЗЬ ==================== */
.connection-input {
    display: flex;
    align-items: center;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 30px;
}

.connection-input label {
    color: #94a3b8;
}

.connection-input input {
    padding: 10px 15px;
    border-radius: 8px;
    border: 2px solid rgba(255, 255, 255, 0.1);
    background: rgba(0, 0, 0, 0.3);
    color: #fff;
    font-size: 1.1em;
    font-family: 'Consolas', monospace;
    width: 200px;
}

.connection-cards {
    display: flex;
    align-items: stretch;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 30px;
}

.connection-card {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
    text-align: center;
    flex: 1;
    min-width: 200px;
    max-width: 280px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.card-icon {
    font-size: 2.5em;
    margin-bottom: 10px;
}

.connection-card h3 {
    color: #00d4ff;
    margin-bottom: 10px;
}

.card-formula {
    background: rgba(0, 0, 0, 0.4);
    padding: 10px;
    border-radius: 8px;
    font-family: 'Cambria Math', serif;
    font-size: 1.2em;
    color: #fff;
    margin-bottom: 15px;
}

.card-desc {
    color: #94a3b8;
    font-size: 0.9em;
    margin-bottom: 8px;
}

.card-visual {
    color: #fbbf24;
    font-size: 0.85em;
    font-style: italic;
}

.card-answer {
    margin-top: 15px;
    padding: 10px;
    background: rgba(16, 185, 129, 0.2);
    border-radius: 8px;
    color: #10b981;
    font-weight: bold;
}

.connection-arrow {
    font-size: 2em;
    color: #7c3aed;
    display: flex;
    align-items: center;
}

.connection-graph {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
    margin-bottom: 25px;
}

.connection-legend {
    display: flex;
    justify-content: center;
    gap: 25px;
    margin-top: 15px;
    flex-wrap: wrap;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9em;
    color: #94a3b8;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.green { background: #10b981; }
.dot.red { background: #ef4444; }
.dot.blue { background: #00d4ff; }

.connection-summary {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 25px;
}

.connection-summary h3 {
    color: #fbbf24;
    margin-bottom: 20px;
    text-align: center;
}

.summary-table {
    width: 100%;
    border-collapse: collapse;
}

.summary-table th, .summary-table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.summary-table th {
    background: rgba(124, 58, 237, 0.2);
    color: #c4b5fd;
}

.summary-table td {
    color: #e0e0e0;
}

/* ==================== КВАДРАТНЫЕ НЕРАВЕНСТВА ==================== */
.quadratic-input {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 25px;
    margin-bottom: 25px;
}

.equation-display {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    font-size: 1.5em;
    margin-bottom: 20px;
}

#quadDisplay {
    font-family: 'Cambria Math', serif;
    color: #fff;
}

#quadSign {
    font-size: 0.8em;
    padding: 8px 15px;
    background: rgba(0, 212, 255, 0.2);
    border: 2px solid #00d4ff;
    border-radius: 8px;
    color: #00d4ff;
}

.quad-controls {
    display: flex;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}

.control-group {
    text-align: center;
}

.control-group label {
    display: flex;
    align-items: center;
    gap: 10px;
    color: #e0e0e0;
    font-size: 1.1em;
}

.control-group input {
    width: 70px;
    padding: 8px;
    border-radius: 8px;
    border: 2px solid rgba(255, 255, 255, 0.1);
    background: rgba(0, 0, 0, 0.3);
    color: #fff;
    font-size: 1em;
    text-align: center;
}

.control-hint {
    display: block;
    color: #94a3b8;
    font-size: 0.8em;
    margin-top: 5px;
}

.quadratic-solution {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
    margin-bottom: 25px;
}

@media (max-width: 900px) {
    .quadratic-solution {
        grid-template-columns: 1fr;
    }
}

.quad-steps {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
}

.quad-step {
    margin-bottom: 20px;
    padding: 15px;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 10px;
    border-left: 3px solid #7c3aed;
}

.quad-step h4 {
    color: #7c3aed;
    margin-bottom: 10px;
    font-size: 0.95em;
}

.quad-step p {
    color: #e0e0e0;
    line-height: 1.6;
}

.quad-step.answer {
    border-left-color: #10b981;
    background: rgba(16, 185, 129, 0.1);
}

.quad-step.answer h4 {
    color: #10b981;
}

.quad-step.answer p {
    font-size: 1.2em;
    font-weight: bold;
    color: #10b981;
}

.quad-graph {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.quadratic-cases {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 25px;
}

.quadratic-cases h3 {
    color: #f472b6;
    margin-bottom: 20px;
    text-align: center;
}

.cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.case-card {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 12px;
    padding: 20px;
    text-align: center;
}

.case-card h4 {
    color: #00d4ff;
    margin-bottom: 15px;
}

.case-card p {
    color: #94a3b8;
    font-size: 0.85em;
    margin-top: 10px;
}

.case-visual {
    margin-bottom: 10px;
}

.case-canvas, .sys-case-canvas {
    background: #0a0a0a;
    border-radius: 8px;
}

/* ==================== МЕТОД ИНТЕРВАЛОВ ==================== */
.equation-builder {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.fraction-display {
    display: flex;
    flex-direction: column;
    align-items: center;
    font-size: 1.3em;
    font-family: 'Cambria Math', serif;
}

.numerator, .denominator {
    padding: 5px 15px;
    min-width: 100px;
    text-align: center;
}

.fraction-line {
    width: 100%;
    height: 2px;
    background: #00d4ff;
}

#signSelect {
    font-size: 1.2em;
    padding: 10px 15px;
    background: rgba(0, 212, 255, 0.2);
    border: 2px solid #00d4ff;
    border-radius: 8px;
    color: #00d4ff;
}

.input-fields {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 20px;
}

.field-group label {
    display: block;
    color: #94a3b8;
    margin-bottom: 5px;
    font-size: 0.9em;
}

.field-group input {
    width: 100%;
    padding: 10px 15px;
    border-radius: 8px;
    border: 2px solid rgba(255, 255, 255, 0.1);
    background: rgba(0, 0, 0, 0.3);
    color: #fff;
    font-family: 'Consolas', monospace;
}

.presets {
    text-align: center;
    margin-top: 15px;
}

.presets p {
    color: #94a3b8;
    margin-bottom: 10px;
}

.preset-btn {
    padding: 8px 15px;
    margin: 5px;
    background: rgba(124, 58, 237, 0.2);
    border: 1px solid #7c3aed;
    border-radius: 20px;
    color: #c4b5fd;
    cursor: pointer;
    transition: all 0.3s;
}

.preset-btn:hover {
    background: rgba(124, 58, 237, 0.4);
}

.step {
    margin-bottom: 20px;
    opacity: 0.5;
    transition: opacity 0.3s;
}

.step.active {
    opacity: 1;
}

.step-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
}

.step-number {
    width: 30px;
    height: 30px;
    background: linear-gradient(135deg, #7c3aed, #f472b6);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
}

.step-title {
    color: #e0e0e0;
}

.step-content {
    padding-left: 42px;
    color: #94a3b8;
    line-height: 1.7;
}

.step-content .highlight {
    color: #00d4ff;
    font-weight: bold;
}

.step-content .root {
    display: inline-block;
    background: rgba(0, 212, 255, 0.2);
    padding: 2px 8px;
    border-radius: 5px;
    color: #00d4ff;
    margin: 2px;
}

.step-content .forbidden {
    display: inline-block;
    background: rgba(239, 68, 68, 0.2);
    padding: 2px 8px;
    border-radius: 5px;
    color: #ef4444;
    margin: 2px;
}

.number-line-container {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 10px;
    padding: 15px;
    overflow-x: auto;
}

.intervals-display {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.interval-card {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 10px;
    padding: 12px 15px;
    text-align: center;
    min-width: 130px;
    border: 2px solid transparent;
}

.interval-card.positive {
    border-color: #10b981;
    background: rgba(16, 185, 129, 0.1);
}

.interval-card.negative {
    border-color: #ef4444;
    background: rgba(239, 68, 68, 0.1);
}

.interval-card .interval-name {
    font-size: 1.1em;
    margin-bottom: 5px;
}

.interval-card .interval-sign {
    font-size: 1.8em;
    font-weight: bold;
}

.interval-card.positive .interval-sign { color: #10b981; }
.interval-card.negative .interval-sign { color: #ef4444; }

.interval-card .test-value {
    font-size: 0.8em;
    color: #94a3b8;
    margin-top: 8px;
}

.answer {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.2), rgba(0, 212, 255, 0.2));
    border: 2px solid #10b981;
    border-radius: 12px;
    padding: 15px;
    font-size: 1.2em;
    text-align: center;
    color: #10b981;
}

/* ==================== СИСТЕМЫ ==================== */
.systems-intro {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 25px;
    margin-bottom: 25px;
}

.system-visual {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 25px;
    flex-wrap: wrap;
}

.system-equation {
    display: flex;
    align-items: center;
    gap: 10px;
}

.brace {
    font-size: 4em;
    color: #7c3aed;
    font-weight: 100;
}

.equations {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.equations input {
    padding: 10px 15px;
    border-radius: 8px;
    border: 2px solid rgba(255, 255, 255, 0.1);
    background: rgba(0, 0, 0, 0.3);
    color: #fff;
    font-family: 'Consolas', monospace;
    font-size: 1.1em;
}

.systems-solution {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
    margin-bottom: 25px;
}

@media (max-width: 900px) {
    .systems-solution {
        grid-template-columns: 1fr;
    }
}

.systems-graph {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.systems-explanation {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 25px;
}

.systems-explanation h3 {
    color: #fbbf24;
    margin-bottom: 15px;
}

.systems-explanation p {
    color: #94a3b8;
    line-height: 1.6;
}

.sys-result {
    margin: 20px 0;
    padding: 15px;
    background: rgba(16, 185, 129, 0.1);
    border-radius: 10px;
    border: 1px solid #10b981;
}

.sys-method {
    margin-top: 20px;
}

.sys-method h4 {
    color: #00d4ff;
    margin-bottom: 10px;
}

.sys-method ol {
    padding-left: 20px;
    color: #94a3b8;
}

.sys-method li {
    margin-bottom: 8px;
}

.systems-cases {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 25px;
}

.systems-cases h3 {
    color: #f472b6;
    margin-bottom: 20px;
    text-align: center;
}

/* ==================== ШПАРГАЛКА ==================== */
.cheat-block {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 25px;
    margin-bottom: 20px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.cheat-block h3 {
    color: #00d4ff;
    margin-bottom: 20px;
    font-size: 1.3em;
}

.cheat-block.main-rule {
    background: linear-gradient(135deg, rgba(124, 58, 237, 0.2), rgba(0, 212, 255, 0.2));
    border: 2px solid #7c3aed;
    text-align: center;
}

.cheat-block.main-rule h3 {
    color: #c4b5fd;
}

.big-text {
    font-size: 1.4em;
    color: #fff;
    margin-bottom: 20px;
}

.rule-example {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
    font-family: 'Consolas', monospace;
    font-size: 1.1em;
    color: #e0e0e0;
}

.rule-example .arrow {
    color: #fbbf24;
    font-size: 1.3em;
}

.rule-example .result {
    color: #10b981;
    font-weight: bold;
    font-size: 1.2em;
}

.cheat-block .hint {
    color: #fbbf24;
    font-style: italic;
    margin-bottom: 15px;
}

.cheat-table {
    width: 100%;
}

.cheat-row {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 15px;
    padding: 12px;
    border-radius: 8px;
    margin-bottom: 8px;
}

.cheat-row.header {
    background: rgba(124, 58, 237, 0.3);
    color: #c4b5fd;
    font-weight: bold;
}

.cheat-row:not(.header) {
    background: rgba(0, 0, 0, 0.2);
    color: #e0e0e0;
}

.cheat-row code, .cheat-row span {
    font-family: 'Consolas', monospace;
}

.cheat-row em {
    color: #10b981;
    font-style: normal;
    font-weight: bold;
}

.mini-rule {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-top: 15px;
    font-size: 1.2em;
    font-weight: bold;
}

.mini-rule .plus { color: #ef4444; }
.mini-rule .minus { color: #10b981; }
.mini-rule .mult { color: #fbbf24; }
.mini-rule .div { color: #00d4ff; }

/* Дроби */
.fraction-case {
    background: rgba(0, 0, 0, 0.2);
    border-radius: 10px;
    padding: 20px;
    margin-bottom: 15px;
}

.fraction-case h4 {
    color: #f472b6;
    margin-bottom: 15px;
}

.fraction-case code {
    background: rgba(0, 212, 255, 0.2);
    padding: 3px 8px;
    border-radius: 5px;
    color: #00d4ff;
}

.steps-mini {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.step-mini {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.step-mini .step-num {
    width: 25px;
    height: 25px;
    background: #7c3aed;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8em;
    font-weight: bold;
}

.step-mini code {
    margin-left: auto;
}

.step-mini em {
    color: #10b981;
    font-style: normal;
    font-weight: bold;
}

/* Типы уравнений */
.equation-types {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 15px;
}

.eq-type {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 12px;
    padding: 15px;
    text-align: center;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.eq-type h4 {
    color: #f472b6;
    margin-bottom: 10px;
    font-size: 0.95em;
}

.eq-type code {
    display: block;
    background: rgba(0, 212, 255, 0.2);
    padding: 8px;
    border-radius: 8px;
    color: #00d4ff;
    margin-bottom: 10px;
    font-size: 1.1em;
}

.eq-type p {
    color: #94a3b8;
    font-size: 0.85em;
    margin-bottom: 5px;
}

.eq-example {
    margin-top: 10px;
    padding: 8px;
    background: rgba(16, 185, 129, 0.1);
    border-radius: 6px;
    color: #94a3b8;
    font-size: 0.85em;
}

.eq-example em {
    color: #10b981;
    font-style: normal;
    font-weight: bold;
}

/* Порядок решения */
.order-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.order-item {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 12px 15px;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 10px;
    border-left: 4px solid #7c3aed;
}

.order-item span {
    width: 30px;
    height: 30px;
    background: linear-gradient(135deg, #7c3aed, #f472b6);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
}

/* Быстрые примеры */
.quick-examples {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.qe-row {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 15px;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 8px;
    font-family: 'Consolas', monospace;
    flex-wrap: wrap;
}

.qe-row .answer {
    background: #10b981;
    color: #fff;
    padding: 3px 12px;
    border-radius: 5px;
    font-weight: bold;
}

/* Ошибки */
.cheat-block.errors h3 {
    color: #ef4444;
}

.errors-table {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.error-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

@media (max-width: 700px) {
    .error-row {
        grid-template-columns: 1fr;
    }
}

.wrong, .right {
    padding: 15px;
    border-radius: 10px;
}

.wrong {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid #ef4444;
}

.right {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid #10b981;
}

.wrong .label, .right .label {
    display: block;
    margin-bottom: 10px;
    font-size: 0.85em;
}

.wrong .label { color: #ef4444; }
.right .label { color: #10b981; }

.wrong code, .right code {
    display: block;
    font-family: 'Consolas', monospace;
    color: #e0e0e0;
}

/* Запоминалка */
.cheat-block.remember {
    background: linear-gradient(135deg, rgba(251, 191, 36, 0.1), rgba(124, 58, 237, 0.1));
    border: 2px solid #fbbf24;
    text-align: center;
}

.cheat-block.remember h3 {
    color: #fbbf24;
}

.remember-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 10px;
    margin-top: 20px;
}

.rem-item {
    background: rgba(0, 0, 0, 0.3);
    padding: 12px;
    border-radius: 8px;
    color: #e0e0e0;
}

.rem-item strong {
    color: #00d4ff;
}

/* Тренажёр */
.cheat-block.trainer {
    border: 2px solid #10b981;
}

.cheat-block.trainer h3 {
    color: #10b981;
}

.trainer-area {
    text-align: center;
}

.trainer-problem {
    margin-bottom: 20px;
}

.problem-eq {
    font-size: 2em;
    font-family: 'Cambria Math', serif;
    color: #fff;
    background: rgba(0, 0, 0, 0.4);
    padding: 20px 40px;
    border-radius: 15px;
    display: inline-block;
}

.trainer-input {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
    margin-bottom: 20px;
}

.trainer-input label {
    font-size: 1.5em;
    color: #e0e0e0;
}

.trainer-input input {
    width: 100px;
    padding: 12px;
    font-size: 1.3em;
    text-align: center;
    border-radius: 10px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    background: rgba(0, 0, 0, 0.3);
    color: #fff;
}

.trainer-input input:focus {
    outline: none;
    border-color: #00d4ff;
}

.trainer-result {
    padding: 15px;
    border-radius: 10px;
    font-size: 1.2em;
    min-height: 50px;
}

.trainer-result.correct {
    background: rgba(16, 185, 129, 0.2);
    color: #10b981;
}

.trainer-result.wrong {
    background: rgba(239, 68, 68, 0.2);
    color: #ef4444;
}

/* Footer */
footer {
    text-align: center;
    padding: 25px;
    color: #64748b;
}

/* Анимации */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}

.tab-content.active {
    animation: fadeIn 0.4s ease-out;
}

/* Адаптивность */
@media (max-width: 600px) {
    header h1 { font-size: 1.6em; }
    .tabs { gap: 5px; }
    .tab { padding: 8px 12px; font-size: 0.8em; }
    .input-fields { grid-template-columns: 1fr; }
    .connection-cards { flex-direction: column; }
    .connection-arrow { transform: rotate(90deg); }
}