/* ============================================
   Crystallographic Visualization Tool
   Updated Design System - Warm Educational Theme
   Based on Figma Design: Warm Educational Tool Website
   ============================================ */

/* ===== CSS Variables (Design Tokens) ===== */
:root {
    /* Colors - Warm Educational Palette */
    --primary-accent: #D62828;
    --primary-accent-dark: #B91C1C;

    --bg-main: #F7F3EE;
    --bg-card: #FFFFFF;
    --bg-canvas: #FFF4ED;
    --bg-highlight: #FFF4ED;

    --border-primary: #E8DFD4;
    --border-highlight: #F9D4C0;

    --text-primary: #2D2520;
    --text-secondary: #6B5A4D;
    --text-muted: #8B7968;
    --text-on-accent: #FFFFFF;

    /* Typography */
    --font-size-base: 16px;
    --font-size-sm: 14px;
    --font-size-xs: 12px;
    --font-size-lg: 18px;
    --font-size-xl: 20px;
    --font-size-2xl: 24px;

    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    --line-height-base: 1.5;

    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 12px;
    --spacing-lg: 16px;
    --spacing-xl: 20px;
    --spacing-2xl: 24px;
    --spacing-3xl: 32px;

    /* Layout */
    --sidebar-width: 320px;
    --header-padding-x: 24px;
    --header-padding-y: 16px;

    /* Border Radius */
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 10px;
    --radius-xl: 12px;
    --radius-2xl: 16px;

    /* 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);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);

    /* Gradients */
    --gradient-accent: linear-gradient(135deg, #D62828 0%, #B91C1C 100%);
    --gradient-canvas: linear-gradient(135deg, #FFF4ED 0%, #F7F3EE 100%);

    /* Transitions */
    --transition-base: all 0.2s ease;
    --transition-colors: colors 0.2s ease;
}

/* ===== Reset & Base Styles ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-main);
    color: var(--text-primary);
    line-height: var(--line-height-base);
    font-size: var(--font-size-base);
    min-height: 100vh;
}

/* ===== Header (Updated to match landing page) ===== */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;600;700&family=Nunito+Sans:wght@400;600;700&display=swap');

body {
    font-family: 'Nunito Sans', -apple-system, BlinkMacSystemFont, sans-serif;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
}

header {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid #E5DDD0;
    position: sticky;
    top: 0;
    z-index: 1002;
}

.header-content {
    max-width: 100%;
    padding: 0.5rem 3rem;
    display: flex;
    align-items: center;
    justify-content: flex-start;
    gap: 3rem;
}

.header-logo {
    flex-shrink: 0;
}

.header-logo img {
    height: 7rem;
    display: block;
}

.header-nav {
    margin-left: auto;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.nav-link, .nav-button {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    color: #2E2E2E;
    background: #FAF6EF;
    border: 1px solid #E5DDD0;
    border-radius: 0.75rem;
    text-decoration: none;
    transition: all 0.2s;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.25rem;
    font-family: 'Nunito Sans', sans-serif;
}

.nav-link:hover, .nav-button:hover {
    color: #D62828;
    background: #FFF5F5;
    border-color: #D62828;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.tools-dropdown {
    position: relative;
}

.dropdown-menu {
    position: absolute;
    top: calc(100% + 0.5rem);
    left: 0;
    width: 16rem;
    background: white;
    border: 2px solid #E5DDD0;
    border-radius: 1rem;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.2s;
}

.tools-dropdown:hover .dropdown-menu,
.tools-dropdown.active .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-category {
    padding: 0.75rem 1.25rem;
    background: #FAF6EF;
    border-bottom: 1px solid #E5DDD0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: #D62828;
    font-weight: 600;
}

.dropdown-item {
    display: block;
    padding: 0.5rem 1.75rem;
    font-size: 0.875rem;
    color: #5E5E5E;
    text-decoration: none;
    border-bottom: 1px solid #F5F0E8;
    transition: all 0.2s;
}

.dropdown-item:hover {
    background: #FFF5F5;
    color: #D62828;
}

.dropdown-item:last-child {
    border-bottom: none;
}

.chevron-icon {
    transition: transform 0.2s;
}

.tools-dropdown:hover .chevron-icon,
.tools-dropdown.active .chevron-icon {
    transform: rotate(180deg);
}

.nav-link:hover {
    background: var(--bg-highlight);
    color: var(--primary-accent);
    border-color: var(--border-highlight);
}

.nav-link.active {
    background: var(--bg-highlight);
    color: var(--primary-accent);
    border-color: var(--border-highlight);
}

/* ===== Main Layout ===== */
.container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
}

.main-content {
    display: flex;
    flex: 1;
    overflow: hidden;
}

/* ===== Sidebar (Control Panel) ===== */
.control-panel {
    width: var(--sidebar-width);
    background: var(--bg-card);
    border-right: 1px solid var(--border-primary);
    overflow-y: auto;
    overflow-x: visible;
    padding: var(--spacing-2xl);
}

.control-panel h2 {
    font-size: var(--font-size-base);
    color: var(--text-primary);
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-2xl);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.control-section {
    margin-bottom: var(--spacing-2xl);
}

.control-section:not(:last-child) {
    padding-bottom: var(--spacing-2xl);
    border-bottom: 1px solid var(--border-primary);
}

.control-section h3 {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    font-weight: var(--font-weight-medium);
    margin-bottom: var(--spacing-lg);
    text-transform: none;
    letter-spacing: normal;
}

/* Form Elements */
select, input[type="number"] {
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    background: var(--bg-card);
    color: #000000;
    transition: var(--transition-base);
    font-family: inherit;
    font-weight: var(--font-weight-medium);
}

select:hover, input[type="number"]:hover {
    border-color: var(--primary-accent);
}

select:focus, input[type="number"]:focus {
    outline: none;
    border-color: var(--primary-accent);
    box-shadow: 0 0 0 3px rgba(217, 119, 87, 0.1);
}

.parameter-group {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.parameter-group label {
    display: flex;
    flex-direction: column;
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    font-weight: var(--font-weight-medium);
}

.parameter-group input {
    margin-top: var(--spacing-xs);
}

.miller-input {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.miller-input.four-index {
    grid-template-columns: repeat(4, 1fr);
}

.miller-input label {
    display: flex;
    flex-direction: column;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--text-secondary);
}

.miller-input input {
    margin-top: var(--spacing-xs);
}

.help-text {
    font-size: var(--font-size-xs);
    color: var(--text-muted);
    font-style: italic;
    margin: var(--spacing-sm) 0 var(--spacing-md) 0;
    line-height: 1.4;
}

/* Checkboxes */
.checkbox-label {
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-md);
    cursor: pointer;
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    padding: var(--spacing-sm) 0;
    transition: var(--transition-colors);
}

.checkbox-label input[type="checkbox"] {
    width: 18px;
    height: 18px;
    margin-right: var(--spacing-md);
    cursor: pointer;
    accent-color: var(--primary-accent);
}

/* Buttons */
.example-btn {
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
    background: var(--bg-highlight);
    color: var(--primary-accent);
    border: 1px solid var(--border-highlight);
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    transition: var(--transition-base);
    font-family: inherit;
}

.example-btn:hover {
    background: var(--bg-card);
    border-color: var(--primary-accent);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.example-btn:active {
    transform: translateY(0);
}

.action-btn {
    width: 100%;
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    background: var(--gradient-accent);
    color: var(--text-on-accent);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-semibold);
    transition: var(--transition-base);
    box-shadow: var(--shadow-sm);
    font-family: inherit;
}

.action-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.action-btn:active {
    transform: translateY(0);
}

#resetBtn {
    background: var(--text-secondary);
    color: var(--text-on-accent);
}

#resetBtn:hover {
    background: var(--text-primary);
}

/* Info Panel */
.info-panel {
    background: var(--bg-highlight);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    font-size: var(--font-size-sm);
    border: 1px solid var(--border-highlight);
    margin-top: var(--spacing-lg);
}

.info-panel p {
    margin-bottom: var(--spacing-md);
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-secondary);
}

.info-panel p:last-child {
    margin-bottom: 0;
}

.info-panel strong {
    color: var(--text-primary);
    font-weight: var(--font-weight-semibold);
}

.info-panel span {
    color: var(--primary-accent);
    font-weight: var(--font-weight-semibold);
    font-family: 'Courier New', monospace;
}

/* ===== Visualization Area ===== */
.visualization-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding: var(--spacing-2xl);
    overflow: hidden;
}

#canvas-container {
    width: 100%;
    height: 100%;
    background: var(--bg-card);
    border: 2px solid var(--border-primary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-sm);
    position: relative;
    overflow: hidden;
}

/* Canvas Background Gradient */
#canvas-container::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient-canvas);
    opacity: 0.3;
    pointer-events: none;
    z-index: 0;
}

/* Instructions Overlay */
.instructions {
    position: absolute;
    bottom: var(--spacing-xl);
    left: 50%;
    transform: translateX(-50%);
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    padding: var(--spacing-md) var(--spacing-2xl);
    border-radius: 30px;
    box-shadow: var(--shadow-md);
    font-size: var(--font-size-xs);
    color: var(--text-muted);
    border: 1px solid var(--border-primary);
    z-index: 10;
}

.instructions strong {
    color: var(--primary-accent);
    font-weight: var(--font-weight-semibold);
}

/* ===== Scrollbar Styling ===== */
.control-panel::-webkit-scrollbar {
    width: 10px;
}

.control-panel::-webkit-scrollbar-track {
    background: var(--bg-main);
    border-radius: 10px;
}

.control-panel::-webkit-scrollbar-thumb {
    background: var(--primary-accent);
    border-radius: 10px;
    border: 2px solid var(--bg-main);
}

.control-panel::-webkit-scrollbar-thumb:hover {
    background: var(--primary-accent-dark);
}

/* ===== Mobile Menu Toggle (Hamburger) ===== */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-around;
    width: 32px;
    height: 32px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 4px;
    position: relative;
    z-index: 1003;
}

.mobile-menu-toggle span {
    width: 100%;
    height: 3px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all 0.3s ease;
    transform-origin: center;
}

.mobile-menu-toggle.active span:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
}

.mobile-menu-toggle.active span:nth-child(2) {
    opacity: 0;
    transform: translateX(-20px);
}

.mobile-menu-toggle.active span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
}

/* Prevent body scroll when menu is open */
body.menu-open {
    overflow: hidden;
}

/* ===== Responsive Design ===== */
@media (max-width: 1200px) {
    .control-panel {
        width: 280px;
    }
}

@media (max-width: 968px) {
    .main-content {
        flex-direction: column;
    }

    .control-panel {
        width: 100%;
        max-height: 300px;
        border-right: none;
        border-bottom: 1px solid var(--border-primary);
    }

    .visualization-area {
        flex: 1;
    }
}

/* ===== Mobile Navigation ===== */
@media (max-width: 768px) {
    /* Show hamburger menu on mobile */
    .mobile-menu-toggle {
        display: flex;
    }

    /* Header adjustments */
    .header-content {
        position: relative;
    }

    .header-logo img {
        height: 80px;
    }

    /* Hide navigation by default on mobile */
    .header-nav {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: var(--bg-card);
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: 80px 24px 24px;
        box-shadow: -4px 0 20px rgba(0, 0, 0, 0.15);
        transition: right 0.3s ease;
        z-index: 1001;
        overflow-y: auto;
    }

    /* Show navigation when active */
    .header-nav.active {
        right: 0;
    }

    /* Mobile nav links */
    .header-nav .nav-link {
        width: 100%;
        text-align: left;
        padding: 16px 20px;
        border-radius: var(--radius-md);
        border: none;
        border-bottom: 1px solid var(--border-primary);
        font-size: var(--font-size-base);
    }

    .header-nav .nav-link:last-child {
        border-bottom: none;
    }

    /* Overlay when menu is open */
    body.menu-open::before {
        content: '';
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0, 0, 0, 0.5);
        z-index: 999;
        animation: fadeIn 0.3s ease;
    }

    @keyframes fadeIn {
        from {
            opacity: 0;
        }
        to {
            opacity: 1;
        }
    }
}

/* ===== Utility Classes ===== */
.text-accent {
    color: var(--primary-accent);
}

.bg-accent {
    background: var(--primary-accent);
}

.border-accent {
    border-color: var(--primary-accent);
}

/* ===== Animation ===== */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.animate-pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* ===== Tooltips ===== */
.info-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 16px;
    height: 16px;
    font-size: 12px;
    color: var(--text-muted);
    cursor: help;
    border-radius: 50%;
    background: var(--bg-highlight);
    border: 1px solid var(--border-highlight);
    transition: var(--transition-base);
    position: relative;
    margin-left: var(--spacing-xs);
}

.info-icon:hover {
    color: var(--primary-accent);
    border-color: var(--primary-accent);
    background: var(--bg-card);
}

.info-icon::before {
    content: attr(data-tooltip);
    position: absolute;
    top: 50%;
    left: calc(100% + 10px);
    transform: translateY(-50%);
    background: var(--text-primary);
    color: var(--text-on-accent);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    font-size: var(--font-size-xs);
    line-height: 1.4;
    white-space: normal;
    width: 220px;
    max-width: calc(100vw - var(--sidebar-width) - 60px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease, transform 0.2s ease;
    z-index: 9999;
    box-shadow: var(--shadow-lg);
    font-weight: var(--font-weight-normal);
}

.info-icon::after {
    content: '';
    position: absolute;
    top: 50%;
    left: calc(100% + 4px);
    transform: translateY(-50%);
    border: 6px solid transparent;
    border-right-color: var(--text-primary);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease;
    z-index: 9999;
}

.info-icon:hover::before,
.info-icon:hover::after {
    opacity: 1;
}