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

:root {
  --blue-dark:  #0f3460;
  --blue-mid:   #1a56a0;
  --blue-light: #2a7de1;
  --blue-pale:  #e8f1fd;
  --white:      #ffffff;
  --bg:         #f4f8ff;
  --text-main:  #1a1f36;
  --text-muted: #5a6478;
  --border:     #dce6f7;
  --radius:     12px;
  --shadow:     0 2px 12px rgba(15,52,96,0.08);
  --green:      #16a34a;
  --green-pale: #dcfce7;
  --red:        #dc2626;
  --red-pale:   #fee2e2;
}

body { font-family: 'Plus Jakarta Sans', Arial, sans-serif; background: var(--bg); color: var(--text-main); line-height: 1.6; }

.skip-link { position: absolute; top: -100px; left: 16px; background: var(--blue-dark); color: #fff; padding: 8px 16px; border-radius: 0 0 var(--radius) var(--radius); font-size: 14px; text-decoration: none; z-index: 999; transition: top 0.2s; }
.skip-link:focus { top: 0; }

/* Header */
.site-header { background: var(--white); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 100; }
.nav-inner { max-width: 1100px; margin: 0 auto; padding: 0 24px; height: 62px; display: flex; align-items: center; justify-content: space-between; }
.logo { font-size: 22px; font-weight: 700; color: var(--blue-dark); letter-spacing: -0.5px; text-decoration: none; }
.logo span { color: var(--blue-light); }
.nav-links { display: flex; gap: 4px; list-style: none; }
.nav-links a { text-decoration: none; font-size: 14px; font-weight: 500; color: var(--text-muted); padding: 6px 14px; border-radius: 8px; transition: background 0.2s, color 0.2s; }
.nav-links a:hover { background: var(--blue-pale); color: var(--blue-light); }

.container { max-width: 1100px; margin: 0 auto; padding: 0 24px; }

/* Breadcrumb */
.breadcrumb-bar { background: var(--white); border-bottom: 1px solid var(--border); padding: 10px 0; }
.breadcrumb { list-style: none; display: flex; align-items: center; gap: 6px; font-size: 13px; color: var(--text-muted); }
.breadcrumb a { color: var(--blue-light); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb li[aria-current="page"] { color: var(--text-main); font-weight: 500; }

/* Hero */
.tool-hero { background: linear-gradient(135deg, var(--blue-dark) 0%, var(--blue-mid) 60%, var(--blue-light) 100%); color: var(--white); text-align: center; padding: 48px 24px 40px; }
.tool-hero-icon { width: 64px; height: 64px; border-radius: 16px; background: rgba(255,255,255,0.15); border: 1px solid rgba(255,255,255,0.3); display: flex; align-items: center; justify-content: center; font-size: 26px; margin: 0 auto 16px; }
.tool-hero h1 { font-size: clamp(24px, 4vw, 38px); font-weight: 700; letter-spacing: -0.5px; margin-bottom: 12px; }
.tool-hero p { font-size: 16px; opacity: 0.88; max-width: 540px; margin: 0 auto; }

/* Tool */
.tool-section { padding: 40px 0; }
.tool-card-main { background: var(--white); border: 1px solid var(--border); border-radius: 16px; padding: 32px; max-width: 640px; margin: 0 auto; box-shadow: var(--shadow); }

/* Upload zone */
.upload-zone { border: 2px dashed var(--border); border-radius: var(--radius); padding: 48px 24px; text-align: center; cursor: pointer; transition: border-color 0.2s, background 0.2s; position: relative; }
.upload-zone:hover, .upload-zone.drag-over { border-color: var(--blue-light); background: var(--blue-pale); }
.upload-zone i { font-size: 40px; color: var(--blue-light); margin-bottom: 14px; display: block; }
.upload-title { font-size: 16px; font-weight: 600; color: var(--text-main); margin-bottom: 4px; }
.upload-sub { font-size: 13px; color: var(--text-muted); }
.upload-zone input[type="file"] { position: absolute; inset: 0; opacity: 0; cursor: pointer; width: 100%; height: 100%; }

/* File info */
.file-info { display: flex; align-items: center; gap: 14px; background: var(--blue-pale); border: 1px solid var(--border); border-radius: var(--radius); padding: 14px 16px; }
.file-info .fa-file-pdf { font-size: 28px; color: var(--blue-light); flex-shrink: 0; }
.file-name { font-size: 14px; font-weight: 600; color: var(--text-main); word-break: break-all; }
.file-meta { font-size: 12px; color: var(--text-muted); margin-top: 2px; }
.file-remove { margin-left: auto; background: none; border: none; color: var(--text-muted); cursor: pointer; font-size: 16px; padding: 4px; border-radius: 50%; transition: color 0.2s, background 0.2s; flex-shrink: 0; }
.file-remove:hover { color: var(--red); background: var(--red-pale); }

/* Options */
.tool-options { margin-top: 24px; }
.option-label { font-size: 13px; font-weight: 600; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.8px; display: block; margin-bottom: 12px; }

/* Split mode buttons */
.split-modes { display: flex; flex-direction: column; gap: 10px; margin-bottom: 20px; }
.split-mode-btn input { display: none; }
.split-mode-btn span { display: flex; align-items: center; gap: 14px; padding: 14px 18px; border-radius: var(--radius); border: 1.5px solid var(--border); background: var(--white); cursor: pointer; transition: all 0.15s; }
.split-mode-btn span i { font-size: 18px; color: var(--blue-light); flex-shrink: 0; width: 20px; text-align: center; }
.split-mode-btn span strong { font-size: 14px; font-weight: 600; color: var(--text-main); display: block; }
.split-mode-btn span small { font-size: 12px; color: var(--text-muted); display: block; margin-top: 2px; }
.split-mode-btn input:checked + span { border-color: var(--blue-light); background: var(--blue-pale); }
.split-mode-btn input:checked + span strong { color: var(--blue-dark); }
.split-mode-btn span:hover { border-color: var(--blue-light); }

/* Extra inputs */
.mode-extra { background: var(--bg); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px; margin-bottom: 16px; }
.extra-label { font-size: 13px; font-weight: 600; color: var(--text-main); display: block; margin-bottom: 8px; }
.text-input { width: 100%; padding: 10px 14px; border: 1.5px solid var(--border); border-radius: 8px; font-size: 14px; font-family: inherit; color: var(--text-main); background: var(--white); transition: border-color 0.15s; outline: none; }
.text-input:focus { border-color: var(--blue-light); }
.text-input.narrow { width: 100px; }
.input-hint { font-size: 12px; color: var(--text-muted); margin-top: 6px; line-height: 1.5; }
.interval-row { display: flex; align-items: center; gap: 10px; }
.interval-unit { font-size: 14px; color: var(--text-muted); }
code { background: var(--border); padding: 1px 6px; border-radius: 4px; font-size: 13px; font-family: monospace; color: var(--blue-dark); }

.btn-action { width: 100%; padding: 14px; border-radius: var(--radius); background: var(--blue-light); color: #fff; border: none; font-size: 16px; font-weight: 600; cursor: pointer; display: flex; align-items: center; justify-content: center; gap: 10px; transition: background 0.2s, transform 0.15s; font-family: inherit; margin-top: 4px; }
.btn-action:hover { background: var(--blue-mid); transform: translateY(-1px); }

/* Progress */
.tool-progress { text-align: center; padding: 20px 0; }
.gs-loading-icon { font-size: 36px; color: var(--blue-light); margin-bottom: 14px; }
.progress-title { font-size: 16px; font-weight: 600; color: var(--text-main); margin-bottom: 16px; }
.progress-bar { background: var(--border); border-radius: 999px; height: 8px; overflow: hidden; }
.progress-fill { height: 100%; background: var(--blue-light); border-radius: 999px; width: 0; transition: width 0.3s ease; }

/* Result */
.tool-result { text-align: center; padding: 16px 0; }
.tool-result .fa-check-circle { font-size: 48px; color: var(--green); margin-bottom: 12px; display: block; }
.tool-result > p { font-size: 16px; font-weight: 600; color: var(--text-main); margin-bottom: 14px; }
.split-summary { font-size: 13px; color: var(--text-muted); background: var(--bg); border: 1px solid var(--border); border-radius: var(--radius); padding: 10px 16px; margin-bottom: 20px; display: inline-block; }
.split-summary strong { color: var(--text-main); }
.btn-download { display: inline-flex; align-items: center; gap: 8px; padding: 12px 28px; background: var(--green); color: #fff; border: none; border-radius: var(--radius); font-size: 15px; font-weight: 600; cursor: pointer; margin-bottom: 12px; transition: background 0.2s; font-family: inherit; }
.btn-download:hover { background: #15803d; }
.btn-again { display: block; margin: 0 auto; background: none; border: none; color: var(--blue-light); font-size: 14px; font-weight: 500; cursor: pointer; text-decoration: underline; font-family: inherit; }

/* Error */
.tool-error { text-align: center; padding: 16px 0; }
.tool-error .fa-exclamation-triangle { font-size: 40px; color: var(--red); margin-bottom: 12px; display: block; }
.tool-error p { font-size: 15px; color: var(--text-muted); margin-bottom: 16px; }

/* Trust */
.trust-row { display: flex; justify-content: center; flex-wrap: wrap; gap: 20px; margin-top: 20px; max-width: 640px; margin-left: auto; margin-right: auto; }
.trust-row span { font-size: 13px; color: var(--text-muted); display: flex; align-items: center; gap: 6px; }
.trust-row i { color: var(--blue-light); }

/* Content */
.content-section { padding: 56px 0; }
.content-grid { display: grid; grid-template-columns: 1fr 300px; gap: 40px; align-items: start; }
.content-main h2 { font-size: 22px; font-weight: 700; color: var(--blue-dark); margin: 32px 0 12px; }
.content-main h2:first-child { margin-top: 0; }
.content-main h3 { font-size: 17px; font-weight: 600; color: var(--text-main); margin: 24px 0 10px; }
.content-main p { font-size: 15px; color: var(--text-muted); margin-bottom: 14px; line-height: 1.7; }
.content-main a { color: var(--blue-light); }
.guide-steps, .guide-list { margin: 0 0 16px 20px; display: flex; flex-direction: column; gap: 10px; }
.guide-steps li, .guide-list li { font-size: 15px; color: var(--text-muted); line-height: 1.65; }
.guide-steps li strong, .guide-list li strong { color: var(--text-main); }

.content-sidebar { display: flex; flex-direction: column; gap: 20px; }
.sidebar-card { background: var(--white); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); }
.sidebar-card h3 { font-size: 13px; font-weight: 700; color: var(--blue-dark); margin-bottom: 14px; text-transform: uppercase; letter-spacing: 0.8px; }
.sidebar-tools { list-style: none; display: flex; flex-direction: column; gap: 2px; }
.sidebar-tools a { display: flex; align-items: center; gap: 10px; padding: 9px 10px; border-radius: 8px; font-size: 14px; font-weight: 500; color: var(--text-main); text-decoration: none; transition: background 0.15s, color 0.15s; }
.sidebar-tools a:hover { background: var(--blue-pale); color: var(--blue-light); }
.sidebar-tools i { color: var(--blue-light); width: 16px; text-align: center; flex-shrink: 0; }
.tip-list { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.tip-list li { font-size: 13px; color: var(--text-muted); display: flex; align-items: flex-start; gap: 8px; line-height: 1.5; }
.tip-list .fa-lightbulb { color: #eab308; margin-top: 2px; flex-shrink: 0; }
.tip-list .fa-code { color: var(--blue-light); margin-top: 2px; flex-shrink: 0; }

/* FAQ */
.section-alt { background: var(--white); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); padding: 56px 0; }
.section-alt h2 { font-size: 26px; font-weight: 700; color: var(--blue-dark); margin-bottom: 10px; }
.section-intro { font-size: 15px; color: var(--text-muted); margin-bottom: 28px; }
.faq-list { display: flex; flex-direction: column; gap: 12px; }
.faq-item { background: var(--bg); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.faq-item summary { padding: 16px 20px; font-size: 15px; font-weight: 600; color: var(--text-main); cursor: pointer; list-style: none; display: flex; justify-content: space-between; align-items: center; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: '+'; font-size: 20px; font-weight: 400; color: var(--blue-light); transition: transform 0.2s; }
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item[open] summary { border-bottom: 1px solid var(--border); color: var(--blue-dark); }
.faq-item p { padding: 16px 20px; font-size: 14px; color: var(--text-muted); line-height: 1.65; }

/* Footer */
.site-footer { background: var(--blue-dark); color: rgba(255,255,255,0.7); padding: 48px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 32px; padding-bottom: 40px; }
.footer-brand { font-size: 20px; font-weight: 700; color: #fff; margin-bottom: 10px; }
.footer-text { font-size: 14px; line-height: 1.6; max-width: 220px; }
.footer-heading { font-size: 12px; font-weight: 700; letter-spacing: 1px; text-transform: uppercase; color: rgba(255,255,255,0.5); margin-bottom: 14px; }
.footer-links { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.footer-links a { color: rgba(255,255,255,0.7); text-decoration: none; font-size: 14px; transition: color 0.2s; }
.footer-links a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.1); padding: 20px 24px; }
.footer-meta { font-size: 13px; color: rgba(255,255,255,0.45); text-align: center; }

@media (max-width: 900px) { .content-grid { grid-template-columns: 1fr; } .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 540px) { .nav-links { display: none; } .tool-card-main { padding: 20px 16px; } .footer-grid { grid-template-columns: 1fr; } }