/* Base Styles */
.base64-app {
    max-width: 1000px;
    margin: 0 auto;
    padding: 25px;
    font-family: 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
    transition: background 0.4s, color 0.4s;
    border-radius: 12px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.05);
}

/* Color Variables */
:root {
    --main-color: #fb6222;
    --main-hover: #e0551a;
    --dark-color: #2f3555;
    --dark-hover: #242a45;
    --white: #ffffff;
    --light-bg: #f9fafc;
    --input-bg: #ffffff;
    --border-color: #e1e5eb;
    --text-color: #2f3555;
    --text-light: #6b7280;
    --error-color: #e53e3e;
    --success-color: #38a169;
    --card-bg: #ffffff;
    --shadow: 0 4px 12px rgba(0,0,0,0.08);
}

[data-theme="dark"] {
    --dark-color: #1c2035;
    --light-bg: #252a42;
    --input-bg: #2f3555;
    --border-color: #3a4060;
    --text-color: #ffffff;
    --text-light: #a0aec0;
    --card-bg: #2f3555;
    --shadow: 0 4px 12px rgba(0,0,0,0.2);
}

.base64-app {
    background-color: var(--light-bg);
    color: var(--text-color);
}

/* Header */
.tool-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 35px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.tool-header h1 {
    margin: 0;
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--dark-color);
    background: linear-gradient(45deg, var(--dark-color), var(--main-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.theme-toggle {
    background: var(--dark-color);
    color: var(--white);
    border: none;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow);
}

.theme-toggle:hover {
    background: var(--dark-hover);
    transform: rotate(15deg);
}

.theme-toggle .moon { display: none; }
[data-theme="dark"] .theme-toggle .sun { display: none; }
[data-theme="dark"] .theme-toggle .moon { display: block; }

/* Section Headers */
.section-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.section-header h2 {
    margin: 0;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--dark-color);
}

.section-header svg {
    color: var(--main-color);
}

/* Inputs & Textareas */
.text-input, .result-output {
    width: 100%;
    padding: 16px;
    margin-bottom: 20px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--input-bg);
    color: var(--text-color);
    font-family: 'Fira Code', 'Courier New', monospace;
    font-size: 15px;
    resize: vertical;
    transition: all 0.3s;
    box-shadow: var(--shadow);
}

.text-input:focus, .result-output:focus {
    outline: none;
    border-color: var(--main-color);
    box-shadow: 0 0 0 3px rgba(251, 98, 34, 0.2);
}

.result-output {
    background-color: var(--card-bg);
    min-height: 120px;
    position: relative;
    padding-right: 50px;
}

/* Buttons */
.button-group {
    display: flex;
    gap: 12px;
    margin-bottom: 20px;
}

.action-btn, .clear-btn, .copy-btn {
    padding: 12px 20px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    font-size: 15px;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    box-shadow: var(--shadow);
}

.action-btn {
    background-color: var(--main-color);
    color: var(--white);
    flex: 1;
}

.action-btn:hover {
    background-color: var(--main-hover);
    transform: translateY(-2px);
}

.clear-btn {
    background-color: var(--dark-color);
    color: var(--white);
}

.clear-btn:hover {
    background-color: var(--dark-hover);
    transform: translateY(-2px);
}

.copy-btn {
    position: absolute;
    top: 10px;
    right: 10px;
    background-color: var(--dark-color);
    color: var(--white);
    padding: 8px 12px;
    font-size: 14px;
}

.copy-btn:hover {
    background-color: var(--dark-hover);
}

.copy-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* Error Message */
.error-message {
    color: var(--error-color);
    margin-top: 5px;
    min-height: 1.5em;
    font-size: 14px;
    font-weight: 500;
}

/* History Section */
.history-section {
    margin-top: 40px;
    padding-top: 25px;
    border-top: 1px solid var(--border-color);
}

.history-section h2 {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--dark-color);
    font-size: 1.4rem;
    margin-bottom: 20px;
}

#history-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 15px;
    margin-bottom: 20px;
}

.history-card {
    background: var(--card-bg);
    border-left: 4px solid var(--main-color);
    padding: 15px;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: var(--shadow);
}

.history-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 16px rgba(0,0,0,0.1);
}

.history-card strong {
    color: var(--main-color);
    font-size: 14px;
}

.history-item {
    font-family: 'Fira Code', monospace;
    font-size: 13px;
    color: var(--text-light);
    margin-top: 8px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Responsive Layout */
.tool-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 35px;
}

@media (min-width: 768px) {
    .tool-container {
        grid-template-columns: 1fr 1fr;
    }
    
    .base64-app {
        padding: 35px;
        margin: 30px auto;
    }
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.tool-section {
    animation: fadeIn 0.4s ease-out;
}

.tool-section:nth-child(2) {
    animation-delay: 0.1s;
}

.history-section {
    animation: fadeIn 0.5s ease-out;
}

/* Success Animation */
@keyframes successPulse {
    0% { box-shadow: 0 0 0 0 rgba(56, 161, 105, 0.4); }
    70% { box-shadow: 0 0 0 10px rgba(56, 161, 105, 0); }
    100% { box-shadow: 0 0 0 0 rgba(56, 161, 105, 0); }
}

.success-pulse {
    animation: successPulse 1s;
}