/* Базовые переменные */
:root {
    --clay-bg: #f0f4f8; 
    --clay-shadow: 5px 5px 10px #d1d9e6, -5px -5px 10px #ffffff;
    --clay-inner: inset 3px 3px 6px rgba(0,0,0,0.05), inset -3px -3px 6px rgba(255,255,255,0.8);
    
    --accent: #3498db;
    --text-main: #2c3e50;
    --text-muted: #7f8c8d;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--clay-bg);
    color: var(--text-main);
    line-height: 1.4;
    /* Убрано жесткое ограничение height: 100vh для корректной работы с мобильной клавиатурой */
    min-height: 100vh; 
    display: flex;
    justify-content: center;
    padding: 15px;
    font-size: 14px;
}

.app-container {
    width: 100%;
    max-width: 1050px;
    display: flex;
    flex-direction: column;
}

/* Шапка платформы */
.clay-header {
    display: flex; justify-content: space-between; align-items: center;
    padding: 10px 20px; margin-bottom: 15px; background: var(--clay-bg);
    border-radius: 16px; box-shadow: var(--clay-shadow);
}

.logo h2 { color: var(--accent); font-weight: 800; font-size: 1.2rem; }

.clay-btn {
    background: var(--clay-bg); border: none; border-radius: 10px;
    padding: 8px 16px; font-weight: 600; color: var(--text-muted); font-size: 0.9rem;
    box-shadow: var(--clay-shadow); cursor: pointer; transition: all 0.2s ease;
    display: flex; align-items: center; gap: 8px; justify-content: center;
}
.clay-btn:active { box-shadow: var(--clay-inner); }

/* Навигация */
.module-nav {
    display: flex; gap: 8px; margin-bottom: 15px;
    background: var(--clay-bg); padding: 6px; border-radius: 12px;
    box-shadow: var(--clay-shadow); overflow-x: auto;
    -ms-overflow-style: none; scrollbar-width: none;
}
.module-nav::-webkit-scrollbar { display: none; }
.nav-tab { padding: 6px 14px; font-weight: bold; color: var(--text-muted); text-decoration: none; border-radius: 8px; font-size: 0.9rem; transition: all 0.2s; white-space: nowrap; }
.nav-tab:hover { background: rgba(255, 255, 255, 0.4); color: var(--text-main); }
.nav-tab.active { background: var(--clay-bg); color: var(--accent); box-shadow: var(--clay-inner); pointer-events: none; }

/* Основная панель */
.clay-panel {
    flex-grow: 1; display: flex; flex-direction: column; justify-content: flex-start;
    padding: 20px; background: var(--clay-bg); border-radius: 16px; box-shadow: var(--clay-shadow);
}

/* Сетка главного меню */
.modules-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 15px; align-content: center; }
.module-card { display: flex; flex-direction: column; align-items: center; text-align: center; padding: 15px; background: var(--clay-bg); border-radius: 16px; box-shadow: var(--clay-shadow); text-decoration: none; color: var(--text-main); transition: transform 0.2s ease; }
.module-card:hover { transform: translateY(-2px); }
.module-card:active { box-shadow: var(--clay-inner); transform: translateY(0); }
.module-icon { font-size: 2.2rem; margin-bottom: 5px; }
.module-card h3 { margin-bottom: 4px; color: var(--accent); font-size: 1rem; }
.module-card p { font-size: 0.8rem; color: var(--text-muted); line-height: 1.2; }
.badge { background: rgba(52, 152, 219, 0.15); color: var(--accent); padding: 2px 8px; border-radius: 8px; font-size: 0.7rem; font-weight: bold; margin-bottom: 8px; box-shadow: inset 2px 2px 4px rgba(0,0,0,0.02), inset -2px -2px 4px #fff; }

footer { margin-top: 20px; text-align: center; }
.teacher-link { color: var(--text-muted); text-decoration: none; font-size: 0.9rem; font-weight: 600; transition: color 0.2s ease; }
.teacher-link:hover { color: var(--accent); }

/* =======================================================================
   ДЕСКТОПНЫЕ ПРАВИЛА ТРЕНАЖЁРОВ
   ======================================================================= */
table { border-spacing: 4px !important; margin-bottom: 10px !important; }
th, td { padding: 6px !important; }
.toggle-cell { width: 35px !important; height: 35px !important; font-size: 1.1rem !important; }
.expression { margin-bottom: 10px !important; padding: 10px !important; font-size: 1.1em !important; }
.task-header { margin-bottom: 10px !important; font-size: 1rem !important; }
.expression-box { padding: 10px !important; margin-bottom: 15px !important; font-size: 1rem !important; }
.feedback-text, .feedback { margin-top: 5px !important; height: 20px !important; }

.module-wrapper { gap: 15px !important; }
.math-board { padding: 15px 20px !important; }
.math-grid { font-size: 20px !important; gap: 5px !important; }
.cell, .input-cell { width: 40px !important; height: 40px !important; }
.carry-cell { width: 28px !important; height: 28px !important; font-size: 14px !important; }
.hex-numpad { padding: 15px !important; gap: 8px !important; }
.numpad-btn { width: 45px !important; height: 45px !important; font-size: 18px !important; }
.translation-board { padding: 15px !important; gap: 10px !important; margin-bottom: 15px !important; }
.original-number { font-size: 24px !important; padding: 10px 20px !important; }
.digit-cell, .base-cell { width: 35px !important; height: 35px !important; }
.power-cell { width: 24px !important; height: 24px !important; font-size: 14px !important; top: 8px !important; right: -8px !important; }

.split-layout { gap: 15px !important; margin-bottom: 10px !important; }
.algorithm-panel { padding: 15px !important; font-size: 14px !important; }
canvas { max-width: 100% !important; height: auto !important; object-fit: contain !important; } 
.board-panel { padding: 15px !important; gap: 15px !important; margin-bottom: 10px !important; }
.num-box { padding: 10px 15px !important; font-size: 20px !important; }
.current-box { font-size: 28px !important; min-width: 90px !important; }
.cmd-btn { padding: 10px 15px !important; font-size: 14px !important; }
.sequence-display { min-height: 50px !important; padding: 10px !important; }
.seq-item { width: 35px !important; height: 35px !important; font-size: 18px !important; }

/* =======================================================================
   МОБИЛЬНАЯ АДАПТАЦИЯ (ВЕРТИКАЛЬНЫЙ СМАРТФОН)
   ======================================================================= */
@media (max-width: 600px) {
    body { padding: 10px; }
    .clay-header { flex-direction: column; gap: 10px; text-align: center; padding: 15px; }
    .clay-panel { padding: 15px 10px; }
    
    /* Таблицы (1-logic) переходят в режим горизонтального скролла */
    table { display: block; overflow-x: auto; white-space: nowrap; width: 100%; border-spacing: 2px !important; }
    
    /* Арифметика (2-num-systems): уменьшение ячеек и перенос клавиатуры */
    .math-board { padding: 10px !important; width: 100%; overflow-x: auto; }
    .math-grid { font-size: 16px !important; gap: 3px !important; }
    .cell, .input-cell { width: 30px !important; height: 30px !important; border-radius: 8px; }
    .carry-cell { width: 22px !important; height: 22px !important; font-size: 12px !important; border-radius: 6px; }
    
    /* Клавиатура складывается в 4 колонки вместо 8 */
    .hex-numpad { grid-template-columns: repeat(4, 1fr) !important; width: 100%; }
    
    /* Удвоитель (4-algorithms): выстраивание элементов в столбик */
    .numbers-display { flex-direction: column; gap: 10px; width: 100%; }
    .arrow { transform: rotate(90deg); margin: -5px 0; }
    .cmd-panel { flex-direction: column; width: 100%; }
    .cmd-btn { width: 100%; }
}