:root {
    --bg-color: #ffffff;
    --text-color: #333333;
    --header-bg: #f5f5f5;
    --link-color: #1976d2;
    --link-hover: #1565c0;
    --border-color: #cccccc;
    --button-bg: #1976d2;
    --button-hover: #1565c0;
    --card-bg: #ffffff;
    --shadow: rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
    --bg-color: #1a1a1a;
    --text-color: #e0e0e0;
    --header-bg: #2a2a2a;
    --link-color: #42a5f5;
    --link-hover: #64b5f6;
    --border-color: #444444;
    --button-bg: #42a5f5;
    --button-hover: #64b5f6;
    --card-bg: #2a2a2a;
    --shadow: rgba(0, 0, 0, 0.3);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s ease, color 0.3s ease;
    line-height: 1.6;
}

header {
    background-color: var(--header-bg);
    padding: 1rem 2rem;
    box-shadow: 0 2px 4px var(--shadow);
    transition: background-color 0.3s ease;
}

header h1 {
    margin: 0 0 1rem 0;
    color: var(--text-color);
}

nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}

nav a {
    color: var(--link-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

nav a:hover {
    color: var(--link-hover);
    text-decoration: underline;
}

main {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 2rem;
}

footer {
    background-color: var(--header-bg);
    padding: 2rem;
    text-align: center;
    margin-top: 4rem;
    transition: background-color 0.3s ease;
}

footer a {
    color: var(--link-color);
    text-decoration: none;
    transition: color 0.2s ease;
}

footer a:hover {
    color: var(--link-hover);
}

#theme-toggle {
    position: fixed;
    top: 1rem;
    right: 1rem;
    background-color: var(--button-bg);
    color: white;
    border: none;
    border-radius: 50px;
    padding: 0.75rem 1.25rem;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    box-shadow: 0 2px 8px var(--shadow);
    transition: all 0.3s ease;
    z-index: 1000;
}

#theme-toggle:hover {
    background-color: var(--button-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--shadow);
}

#theme-toggle:active {
    transform: translateY(0);
}

#theme-toggle:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(25, 118, 210, 0.3);
}

.theme-icon {
    font-size: 1.2rem;
    line-height: 1;
}

.theme-text {
    font-size: 0.9rem;
}

@media (max-width: 768px) {
    #theme-toggle {
        padding: 0.6rem 1rem;
        font-size: 0.85rem;
    }

    .theme-text {
        display: none;
    }

    .theme-icon {
        font-size: 1.4rem;
    }
}

@media (prefers-reduced-motion: reduce) {
    * {
        transition: none !important;
    }
}

.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.controls {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-top: 1rem;
    align-items: center;
}

.controls button {
    padding: 0.75rem 1.25rem;
    background-color: var(--button-bg);
    color: white;
    border: none;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s ease, transform 0.1s ease;
}

.controls button:hover {
    background-color: var(--button-hover);
    transform: translateY(-1px);
}

.controls button:active {
    transform: translateY(0);
}

.controls button:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(25, 118, 210, 0.3);
}

.status {
    font-size: 0.95rem;
    color: var(--text-color);
}

.crud-layout {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.panel {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 2px 8px var(--shadow);
}

.panel h2 {
    margin-top: 0;
}

.panel form {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.panel label {
    font-weight: 600;
}

.panel input,
.panel textarea,
.panel select {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--bg-color);
    color: var(--text-color);
}

.panel textarea {
    min-height: 100px;
    resize: vertical;
}

.panel button {
    align-self: flex-start;
}